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1.
Phys Chem Chem Phys ; 25(48): 33081-33093, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38037878

RESUMO

The work function (WF) of perovskite materials is essential for developing optoelectronic devices enabling efficient charge transfer at their interfaces. Perovskite's WF can be tuned by MXenes, a new class of two-dimensional (2D) early transition metal carbides, nitrides, and carbonitrides. Their variable surface terminations or the possibility of introducing elemental dopants could advance perovskites. However, the influence of doped-MXenes on perovskite materials is still not fully understood and elaborated. This study provides mechanistic insight into verifying the tunability of MAPbI3 WF by hybridizing with fluorine-terminated Ti3C2Tx (F-MXene) and nitrogen-doped Ti3C2Tx (N-MXene). We first reveal the interfacial interaction between MAPbI3 and MXenes via X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and photoluminescence spectroscopy (PL). UPS supported by density functional theory (DFT) calculations allowed the description of the influence of F and N on MXene's WF. Furthermore, we developed MAPbI3/MXene heterostructures using F- and N-MXenes. The F-MXenes extended the most WF of MAPbI3 from 4.50 eV up to 3.00 eV, compared to only a small shift for N-MXene. The underlying mechanism was charge transfer from low WF F-MXene to MAPbI3, as demonstrated by PL quenching in MAPbI3/F-MXene heterostructures. Altogether, this work showcases the potential of fluorine-doped MXenes over nitrogen-doped MXenes in advancing perovskite heterostructures, thus opening a door for efficient optoelectronic devices.

2.
Int J Mol Sci ; 22(24)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34948005

RESUMO

In this work, NiTi alloy parts were fabricated using laser powder bed fusion (LBPF) from pre-alloyed NiTi powder and in situ alloyed pure Ni and Ti powders. Comparative research on the corrosive and biological properties of both studied materials was performed. Electrochemical corrosion tests were carried out in phosphate buffered saline at 37 °C, and the degradation rate of the materials was described based on Ni ion release measurements. Cytotoxicity, bacterial growth, and adhesion to the surface of the fabricated coupons were evaluated using L929 cells and spherical Escherichia coli (E. coli) bacteria, respectively. The in situ alloyed NiTi parts exhibit slightly lower corrosion resistance in phosphate buffered saline solution than pre-alloyed NiTi. Moreover, the passive layer formed on in situ alloyed NiTi is weaker than the one formed on the NiTi fabricated from pre-alloyed NiTi powder. Furthermore, in situ alloyed NiTi and NiTi made from pre-alloyed powders have comparable cytotoxicity and biological properties. Overall, the research has shown that nitinol sintered using in situ alloyed pure Ni and Ti is potentially useful for biomedical applications.


Assuntos
Ligas/farmacologia , Escherichia coli/fisiologia , Níquel/química , Titânio/química , Ligas/química , Animais , Aderência Bacteriana/efeitos dos fármacos , Linhagem Celular , Corrosão , Escherichia coli/efeitos dos fármacos , Teste de Materiais , Camundongos , Fosfatos/química , Pós , Propriedades de Superfície
3.
Entropy (Basel) ; 23(7)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34356431

RESUMO

In this paper, we study economic growth and its volatility from an episodic perspective. We first demonstrate the ability of the genetic algorithm to detect shifts in the volatility and levels of a given time series. Having shown that it works well, we then use it to detect structural breaks that segment the GDP per capita time series into episodes characterized by different means and volatility of growth rates. We further investigate whether a volatile economy is likely to grow more slowly and analyze the determinants of high/low growth with high/low volatility patterns. The main results indicate a negative relationship between volatility and growth. Moreover, the results suggest that international trade simultaneously promotes growth and increases volatility, human capital promotes growth and stability, and financial development reduces volatility and negatively correlates with growth.

4.
Inorg Chem ; 58(11): 7602-7614, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31117635

RESUMO

Among two-dimensional (2D) materials, such as graphene, a new family of 2D anisotropic carbides and nitrides of early transition metals (MXenes) is very interesting because of the potential applications in electronics, medicine, and photocatalysis. In this paper, preparation, morphostructural characterization, band gaps determination, and salicylic acid photodegradation ability of Ti2C MXene and six nanocomposites consisting of the MXene modified by TiO2, Ag2O, Ag, PdO, Pd, and Au are reported. It was confirmed using electron diffraction studies, energy dispersive X-ray spectroscopy, and high-resolution transmission microscopy that metals and metal oxides occur on the MXene flakes as nanoparticles in a shape of spots. The band gaps determined experimentally using Tauc's method are placed in the region of 0.90-1.31 eV. In recent years, the method of photocatalytic decomposition of pollutants using semiconductor photocatalysts and UV-vis energy has become increasingly important. The MXene based nanocomposites revealed high activity in the salicylic acid (SA) photodegradation reaction (86.1-97.1% of degraded SA after 3 h, concentration of SA initial solution 100 µM, the circulation rate of the SA solution 0.875 cm3/min). The interfacial charge transfer mechanism and the role of the metallic and metal oxide nanoparticles in the photocatalytic activity of the MXene based nanocomposites are presented and discussed.

5.
J Clin Ultrasound ; 47(5): 261-266, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30729529

RESUMO

PURPOSE: Lung ultrasound (LUS) examination is used to evaluate patients with acute respiratory failure. The physiological LUS pattern during labor in healthy parturients has not been well described. The aim of this study was to evaluate the LUS pattern in a cohort of healthy women during uncomplicated labor. METHODS: We used the 8-point LUS assessment protocol and investigated lung sliding, A-lines, B-lines, interstitial syndrome, lung consolidation, and pleural effusion according to the International Consensus Document with two additional supradiaphragmatic projections. All patients were screened twice; once during the first stage of labor and again within 2 hours after delivery. RESULTS: We included 24 patients in this study from February 2014 to August 2015. A total of 480 LUS records were retained for further analysis. Overall, 16 of 24 patients (67%) had at least one positive region (three or more B-lines) during the peridelivery LUS evaluation. Interstitial syndrome was detected in five patients (21%). There were no differences in A-line (P = 0.38) or B-line (P = 0.68) prevalence between LUS examinations before and after delivery. CONCLUSIONS: Women in uncomplicated labor can present abnormal LUS findings, which may affect the interpretation of LUS results in patients with respiratory deterioration. Further studies should address this topic in larger cohort of patients.


Assuntos
Trabalho de Parto/fisiologia , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Complicações do Trabalho de Parto/diagnóstico por imagem , Adulto , Feminino , Humanos , Pulmão/fisiologia , Doenças Pulmonares Intersticiais/fisiopatologia , Complicações do Trabalho de Parto/fisiopatologia , Projetos Piloto , Gravidez , Estudos Prospectivos , Valores de Referência , Ultrassonografia
6.
RSC Adv ; 14(24): 17234-17235, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38831772

RESUMO

Diana Berman, Agnieszka Jastrzebska, Massimiliano Papi, and Andreas Rosenkranz introduce the RSC Advances themed issue on 2D materials and their applications.

7.
Sci Rep ; 13(1): 19498, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945713

RESUMO

The study aimed to investigate the usefulness of the Running-based Anaerobic Sprint Test (RAST) in anaerobic performance estimation in trained and untrained girls U12, and the effect of an 8-week training period in female U12 soccer players on anaerobic performance. A comparative study of two structurally different anaerobic tests was performed to reach the goal. The study was designed as a non-randomized, controlled before-and-after trial. Fourteen female soccer players (FSP) and twelve untrained girls (UNT) participated in the study. During that time, all participants were subjected to school's physical education classes and the FSP additionally participated in regular soccer training. The anaerobic performance was evaluated twice, within 8-weeks period, using the traditional Wingate test (WAnT) and the RAST. A significant increase in the anaerobic performance of the FSP was noted (p < 0.05). In both tests peak, average, and relative power were significantly improved (p < 0.005). Nevertheless, strong, statistically significant (p < 0.05) correlation coefficients (0.50 < r < 0.70) were found for pre-training measurements between the WAnT and the RAST power parameters in absolute values. In UNT group significant improvement was found in peak, average and min power (p < 0.05) in the RAST. The improvement in anaerobic performance after training along with the strong correlation noted between the WAnT and the RAST power parameters prove the usefulness of the RAST in assessing anaerobic capacity in female youth athletes. Its simplicity encourages its use in monitoring anaerobic capacity in both trained and untrained girls.


Assuntos
Desempenho Atlético , Futebol , Adolescente , Feminino , Humanos , Limiar Anaeróbio , Anaerobiose , Atletas , Teste de Esforço
8.
IEEE Trans Cybern ; 53(2): 1348-1359, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34936564

RESUMO

This article presents a comprehensive approach for time-series classification. The proposed model employs a fuzzy cognitive map (FCM) as a classification engine. Preprocessed input data feed the employed FCM. Map responses, after a postprocessing procedure, are used in the calculation of the final classification decision. The time-series data are staged using the moving-window technique to capture the time flow in the training procedure. We use a backward error propagation algorithm to compute the required model hyperparameters. Four model hyperparameters require tuning. Two are crucial for the model construction: 1) FCM size (number of concepts) and 2) window size (for the moving-window technique). Other two are important for training the model: 1) the number of epochs and 2) the learning rate (for training). Two distinguishing aspects of the proposed model are worth noting: 1) the separation of the classification engine from pre- and post-processing and 2) the time flow capture for data from concept space. The proposed classifier joins the key advantage of the FCM model, which is the interpretability of the model, with the superior classification performance attributed to the specially designed pre- and postprocessing stages. This article presents the experiments performed, demonstrating that the proposed model performs well against a wide range of state-of-the-art time-series classification algorithms.

9.
Sci Rep ; 13(1): 15882, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741888

RESUMO

The study was conducted to determine thecorrelation between the selected measures of aerobic physical efficiency and changes in the temple surface temperature in response to light and heavy exercise. 25 physically active men aged 19-25 were recruited for the study. They performed a graded exercise test on a cycle ergometer to measure maximum power (Pmax) and a test verifying the value of maximum oxygen uptake (VO2max). Then, two 3-min submaximal efforts with constant-intensity of 2.2 W·kgLBM-1 and 5 W·kgLBM-1, respectively were performed. During the constant-intensity efforts, the temperature of the temple surface was measured. Then, the difference between the temperature of the temple measured at the end of the exercise and the temperature measured at the beginning of the exercise was calculated (ΔT1-2.2, ΔT1-5, respectively). It was shown that ΔT1-2.2 correlated statistically significantly with VO2max (ml·min-1·kg-1) (r = 0.49; p = 0.01) and Pmax (W·kg-1) (r = 0.41, p = 0.04). Moreover, ΔT1-5 correlated statistically significantly with VO2max (l·min-1) (r = - 0.41; p = 0.04). Changes in body surface temperature in response to light exercise positively correlate with measurements of aerobic physical efficiency, such as VO2max and Pmax. When the exercise intensity is high (5 W·kgLBM-1), the correlation between exercise body temperature changes and VO2max becomes negative.


Assuntos
Consumo de Oxigênio , Oxigênio , Masculino , Humanos , Consumo de Oxigênio/fisiologia , Temperatura , Exercício Físico/fisiologia , Temperatura Corporal/fisiologia , Teste de Esforço
10.
IEEE Trans Cybern ; 53(7): 4665-4676, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34951861

RESUMO

A fuzzy cognitive map (FCM) is a graph-based knowledge representation model wherein the connections of the nodes (edges) represent casual relationships between the knowledge items associated with the nodes. This model has been applied to solve various modeling tasks including forecasting time series. In the original FCM-based forecasting model, causal relationships among concepts of the FCM remain unchanged. However, causal relationships may change in time. Therefore, we propose a new learning method for training an FCM resulting in an adaptive FCM which consists of several sub-FCMs. It can select different sub-FCMs at different moments. In an active processing scenario, in which we deal with a large-scale time series with new data being continuously generated, a forecasting model built on the old data should be updated when the new data arrive. Furthermore, retraining an FCM from scratch entails increasing computing overhead that will become a serious obstacle in many practical scenarios. To overcome the above-mentioned shortcomings, this study offers an original design setting in which the FCM is updated by knowledge-guidance learning mechanism for the first time. Compared with the existing classical forecasting models, the proposed model shows higher accuracy and efficiency. Its increased performance is demonstrated through a series of reported experimental studies.


Assuntos
Algoritmos , Lógica Fuzzy , Fatores de Tempo , Aprendizagem , Cognição
11.
Materials (Basel) ; 16(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36837159

RESUMO

Dyes are highly toxic and persistent in the environment. Their presence in water causes environmental and social problems. Dyes must be effectively removed from the water. A UV/ZVI/H2O2 process was applied to decompose two organic dyes, AM E123 and AM ACID. A commercial ZVI product, Ferox Flow, was used, and its properties were determined using SEM and XRF. The zeta potential, surface area, and optical properties of ZVI were also determined. The efficiency of dye removal in optimal conditions was 85.5% and 80.85% for AM E123 and AM ACID, respectively. Complete decolorization was observed in all samples. The decomposition of both dyes occurred according to a modified pseudo-second-order reaction and there was a statistically significant correlation between the TOC decrease, pH, and process time. The catalyst was observed to have high stability, and this was not affected by the performance of the treatment process even after the third cycle, as confirmed by the results of the catalyst surface analysis and iron diffusion test. Slight differences in process efficiency were observed after each cycle. The need for only a small amount of catalyst to decompose AM E123 and AM ACID, coupled with the ability to reuse the catalyst without the need for prior preparation, may reduce catalyst purchase costs.

12.
Environ Sci Pollut Res Int ; 30(26): 69024-69041, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37129809

RESUMO

In an era of increasing environmental awareness, it is very important to work towards eliminating or at least reducing as many harmful industrial substances as possible. However, the implementation of green chemistry methods for wastewater treatment can be difficult especially due to complexity, the high cost of reagents, and the required long process time. This paper focuses on using waste iron (WI) to remove two kinds of amaranth dye commonly used in industry. To enhance the process, UV irradiation and hydrogen peroxide were used. The novelty of the research was the use of efficient and reusable WI as a heterogeneous catalyst in the process. WI material characteristics was done before and after the process using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray fluorescence (XRF). Zeta potential, size characterization, circularity, and direct band gap were also determined. As a result of treatment complete decolorization of both dyes was achieved, as well as 99% absorbance removal after 15-min process time. The total organic carbon (TOC) decrease after 60-min process time was in the range from 86.6 to 89.8%. Modified pseudo-second-order reaction reflects obtained results of treatment efficiency. Treatment results, confirmed by WI material characterization, indicate satisfactory stability of the catalyst and good oxidation capacity.


Assuntos
Ferro , Poluentes Químicos da Água , Ferro/química , Corantes/química , Corante Amaranto , Oxirredução , Microscopia Eletrônica de Varredura , Catálise , Resíduos , Resíduos Industriais , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
13.
Small Methods ; 7(8): e2201252, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36879487

RESUMO

Two-dimensional MXenes are excellent photocatalysts. However, their low oxidation stability makes controlling photocatalytic processes challenging. For the first time, this work elucidates the influence of the oxidation stabilization of model 2D Ti3 C2 Tx MXene on its optical and photocatalytic properties. The delaminated MXene is synthesized via two well-established approaches: hydrofluoric acid/tetramethylammonium hydroxide (TMAOH-MXene) and minimum intensive layer delamination with hydrochloric acid/lithium fluoride (MILD-MXene) and then stabilized by L-ascorbic acid. Both MXenes at a minimal concentration of 32 mg L-1 show almost 100% effectiveness in the 180-min photocatalytic decomposition of 25 mg L-1 model methylene blue and bromocresol green dyes. Industrial viability is achieved by decomposing a commercial textile dye having 100 times higher concentration than that of model dyes. In such conditions, MILD-MXene is the most efficient due to less wide optical band gap than TMAOH-MXene. The MILD-MXene required only few seconds of UV light, simulated white light, or 500 nm (cyan) light irradiation to fully decompose the dye. The photocatalytic mechanism of action is associated with the interplay between surface dye adsorption and the reactive oxygen species generated by MXene under light irradiation. Importantly, both MXenes are successfully reused and retained approximately 70% of their activity.

14.
Biomater Adv ; 153: 213581, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37572598

RESUMO

Two-dimensional (2D) transition metal carbides/nitrides (MXenes) are potential antibacterial agents. However, their activity against microorganisms is not fully understood. It could relate to MXenes' surface which further influences their biocidal action. Herein, we report no continuous biocidal activity for delaminated 2D niobium-based MXenes (Nbn+1XnTx) such as Nb2CTx and Nb4C3Tx prepared with HF/TMAOH protocol. Biocidal activity towards Bacillus subtilis and Staphylococcus aureus microorganisms was achieved by surface-functionalization with lysozyme macromolecule. MXenes' engineering with lysozyme changed MXene's surface charge from negative into positive thus enabling the elimination of bacteria cells during 48 h of incubation. In contrast, Nb4C3Tx functionalized with collagen stimulated the growth of Bacillus subtilis by 225 %, showing MXene's biocompatibility towards this particular strain. Altogether, our results show that MXenes are incredibly bio-tunable. Opposing bio-effects such as antimicrobial or growth-stimulating can be achieved towards various microorganisms with rational surface engineering.


Assuntos
Muramidase , Nióbio , Antibacterianos/farmacologia , Bacillus subtilis
15.
Adv Mater ; 35(42): e2301850, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37715336

RESUMO

The vertical integration of distinct 2D materials in van der Waals (vdW) heterostructures provides the opportunity for interface engineering and modulation of electronic as well as optical properties. However, scarce experimental studies reveal many challenges for vdW heterostructures, hampering the fine-tuning of their electronic and optical functionalities. Optically active MXenes, the most recent member of the 2D family, with excellent hydrophilicity, rich surface chemistry, and intriguing optical properties, are a novel 2D platform for optoelectronics applications. Coupling MXenes with various 2D materials into vdW heterostructures can open new avenues for the exploration of physical phenomena of novel quantum-confined nanostructures and devices. Therefore, the fundamental basis and recent findings in vertical vdW heterostructures composed of MXenes as a primary component and other 2D materials as secondary components are examined. Their robust designs and synthesis approaches that can push the boundaries of light-harvesting, transition, and utilization are discussed, since MXenes provide a unique playground for pursuing an extraordinary optical response or unusual light conversion features/functionalities. The recent findings are finally summarized, and a perspective for the future development of next-generation vdW multifunctional materials enriched by MXenes is provided.

16.
ACS Appl Mater Interfaces ; 15(37): 44075-44086, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37682978

RESUMO

Solution-based processing offers advantages for producing thin films due to scalability, low cost, simplicity, and benignity to the environment. Here, we develop conductive and photoactivated self-cleaning reduced graphene oxide (rGO)/Ti3CNTx MXene thin films via spin coating under ambient conditions. The addition of a thin rGO layer on top of Ti3CNTx resulted in up to 45-fold improvement in the environmental stability of the film compared to the bare Ti3CNTx film. The optimized rGO/Ti3CNTx thin film exhibits an optical transmittance of 74% in the visible region of the spectrum and a sheet resistance of 19 kΩ/sq. The rGO/Ti3CNTx films show high rhodamine B discoloration activity upon light irradiation. Under UV irradiation, the electrically conductive MXene in combination with in situ formed semiconducting titanium oxide induces photogenerated charge carriers, which could potentially be used in photocatalysis. On the other hand, due to film transparency, white light irradiation can bleach the adsorbed dye via photolysis. This study opens the door for using MXene thin films as multifunctional coatings with conductive and potentially self-cleaning properties.

17.
Przegl Lek ; 69(5): 184-93, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-23050414

RESUMO

PURPOSE OF THE STUDY: To compare predicted death rate (PDR) numbers, computed in commonly used severity-of-illness and prognostic scoring systems (Portsmouth-POSSUM, SAPS 2, MPM 2, MPM for cancer patients, LODS, ODIN i TRIOS) on the first and on the third postoperative days with the mean PDR calculated from the scales. Assessment of the mean PDR values. Analysis of the main risk factors that affect postoperative mortality. MATERIAL AND METHODS: There were analyzed 187 cases of non-survivors and 100 cases of survivors treated in surgical wards at University Hospital in Kraków. In each case there were compared groups of patients with defined pathological syndromes (sepsis, thromboembolism, left-heart failure, respiratory tract infections, trauma, oncology, multiorgan failure and haemorrhage) with PDR calculated in seven severity-of illness and prognostic scoring systems on the first and on the third postoperative day and mean PDR computed from seven PDR numbers. There was used calculation of OR (odds ratio) with 95% CI (confidence interval) and the Pearson product moment correlation coefficient. RESULTS: The main risk factors of early deaths (that occurred within the first 3 postoperative days) in the group of nonsurvivors (n = 187) were: emergencies (p < 0.001), perioperative haemorrhage (p < 0.002), and trauma (p = 0.02). The late deaths (that occurred > 3 postoperative days) were caused by repeated surgery (p < 0.001), oncology (p = 0.019), then comorbidities (p = 0.025) and sepsis (p = 0.072). The Pearson product moment correlation coefficients for mean PDR computed on the 1st and 3rd postoperative day were respectively -0.4517 and -0.4012. None of the scales showed good discriminant characteristics in patients with cardiovascular diseases and pneumonia. In all scoring systems, except of the MPM for cancer patients and TRIOS, the PDR values correlated significantly with the preoperative ASA group assessment. CONCLUSIONS: There is no commonly used severity-of-illness scoring system that could properly evaluate intensive care unit patients. Discriminative abilities of the scoring systems do not present any unique features that might affect selection of one of them. The mean PDR value computed from available scales is a reasonable descriptive and prognostic alternative.


Assuntos
Causas de Morte , Inquéritos Epidemiológicos/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Índice de Gravidade de Doença , Procedimentos Cirúrgicos Operatórios/mortalidade , Humanos , Polônia/epidemiologia , Prognóstico , Fatores de Risco , Taxa de Sobrevida
18.
Przegl Lek ; 69(4): 129-36, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-23029705

RESUMO

PURPOSE OF THE STUDY: To compare and evaluate preoperative assessment in ASA scale to predicted death rate (PDR) numbers, computed in commonly used severity-of-illness and prognostic scoring systems (Portsmouth-POSSUM, SAPS 2, MPM 2, MPM for cancer patients, LODS, ODIN i TRIOS) on the first and on the third postoperative days. Evaluation of the mean PDR calculated from the scales. MATERIAL AND METHODS: There were analyzed 187 cases of non-survivors and 100 cases of survivors of 187 patients treated in surgical intensive care unit at University Hospital in Kraków. In each case PDR was calculated in seven severity-of illness and prognostic scoring systems on the first and on the third postoperative day and compared to the ASA group and mean PDR computed from seven PDR numbers. Discrimination and calibration characteristics of the scoring systems was analyzed as area under receiver operating characteristic curves (AUROC) and predictive values. RESULTS: Length of hospital stay was shorter in survivors (16.6 days) as compared to nonsurvivors (25.3 days); similarly the time period between the hospital admittance and surgery was shorter in survivors (1.6 days vs 7.4 days). There were almost twice more frequent repeated surgical procedures in nonsurvivors (45.4% vs 26%). The mean ASA scale in non-survivors was 3.74 and 3.20 in survivors (p < 0.001). The mean PDR computed from seven scoring systems on the first postoperative day was 55.2 in non-survivors vs 21.2 in survivors (p < 0.001) and on the third postoperative day was 64.1 vs 32.3 (p < 0.001). The best discriminative properties, calculated as AUROC, showed: mean PDR computed from the used scoring systems on the first postoperative day (0.859), then ODIN (0.847), MPM2 (0.833), Portsmouth-POSSUM (0.83) and mean PDR computed on the third postoperative day (0827). CONCLUSIONS: There is none severity-of-illness nor prognostic scoring system that could be commonly used in intensive care unit patients. There are discrepancies in predicted death rate (PDR) cal. culated in each of available risk models in population of intensive care unit patients. The mean PDR value computed from available scales could be a reasonable descriptive and prognostic alternative.


Assuntos
Cuidados Críticos/métodos , Cuidados Críticos/estatística & dados numéricos , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/mortalidade , Índice de Gravidade de Doença , Sobreviventes/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Polônia , Período Pós-Operatório , Prognóstico , Curva ROC , Análise de Sobrevida , Adulto Jovem
19.
Biology (Basel) ; 11(7)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-36101329

RESUMO

The aim of this study was to determine whether there are associations between cardiovascular fitness (and aerobic capacity) and changes in temporal skin temperature during and after a single bout of high-intensity exercise. Twenty-three men with varying levels of physical activity (VO2max: 59.03 ± 11.19 (mL/kg/min), body mass 71.5 ± 10.4 (kg), body height 179 ± 8 (cm)) participated in the study. Each subject performed an incremental test and, after a 48-h interval, a 110%Pmax power test combined with an analysis of the thermal parameters, heart rate recovery and heart rate variability. Thermal radiation density from the body surface (temple) was measured using a Sonel KT384 thermal imaging camera immediately after warm-up (Tb), immediately after exercise (Te) and 120 sec after the end of exercise (Tr). The differences between measurements were then calculated. The correlation analysis between the thermal and cardiovascular function parameters during the recovery period showed strong positive associations between the Tr-Te difference and measures of cardiovascular fitness (50 < r < 69, p < 0.05). For example, the correlation coefficient between Tr-Te and VO2max reached 0.55 and between Tr-Te and Pmax reached 0.68. The results obtained indicate that the measurement of temporal temperature during and after an intense 3-min bout of exercise can be used to assess aerobic physical capacity and cardiovascular fitness.

20.
Biomolecules ; 12(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36291724

RESUMO

The metabolization of carbohydrates by Streptococcus mutans leads to the formation of lactic acid in the oral cavity, which can consequently accelerate the degradation of dental implants fabricated from commercially available microcrystalline Ti. Microstructure influences surface topography and hence interaction between bacteria cells and Ti surfaces. This work offers the first description of the effect of S. mutans on the surface topography and properties of nanostructured bulk Ti, which is a promising candidate for modern narrow dental implants owing to its superior mechanical strength. It was found that S. mutans incubation resulted in the slight, unexpected decrease of surface nanoroughness, which was previously developed owing to privileged oxidation in areas of closely spaced boundaries. However, despite the changes in nanoscale surface topography, bacteria incubation did not reduce the high level of protection afforded by the oxide layer formed on the nanostructured Ti surface. The results highlight the need-hitherto ignored-to consider Ti microstructure when analyzing its behavior in the presence of carbohydrate-metabolizing bacteria.


Assuntos
Implantes Dentários , Streptococcus mutans , Corrosão , Titânio/química , Propriedades de Superfície , Óxidos/farmacologia , Carboidratos/farmacologia , Ácido Láctico/metabolismo
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