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Contamination soils with heavy metals is a problem with high interest, because contamination with heavy metals affect food chains and human health by intake and accumulation in living beings. Although all of these methods not quite effective for recovering contaminated environments, however they are still good options for recovering contaminated soils. In this research evaluated the recovering potential in different concentrations and combinations of dolomite with additives like zerovalent iron, Fe-Mn concretions, iron powder, ferrihydrite and iron nanoparticles. With these treatments, achieved reduction of concentration of all heavy metals founded (Co, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and also reduction in toxicity, confirmed with a biotest with Daphnia magna. These findings confirms that the optimal remediants are nanoparticles with biochar and iron powder with and without biochar.

The analysis of the scientific literature on the subject of bioremediation in Latin America countries shows that due to the excessive and uncontrolled use of pesticides in agriculture, there are negative impacts on the environment, mainly on soil and water, as well as on human health. However, through processes such as bioremediation, which utilize the metabolic potential of microorganisms such as bacteria and fungi, it is possible to reduce the impact of pesticides on the environment and human health, which are key factors for achieving sustainable development. Colombia has a severe pesticide pollution problem, as the uncontrolled use of pesticides has affected not only the environment but also human health. Thus, bioremediation is a good alternative to the restoration of a polluted environment and the reduction of its impact on human health.

Haemonchus contortus and Trichostrongylus colubriformis are the most important gastrointestinal nematodes causing serious losses in sheep production of tropical and subtropical regions. Prophylaxis of gastrointestinal nematode infections is based on anthelmintics use, but their frequent administration selects multiple-resistant parasites. To evaluate how the situation has changed over the last decades, the anthelmintic resistance status of gastrointestinal nematodes in sheep flocks was assessed in the current study and compared to previous surveys. In each one of the 15 flocks evaluated, animals (n ≥ 7) were allocated into at least five groups and treated as follows: 1) untreated control; 2) albendazole; 3) levamisole; 4) ivermectin; and 5) monepantel. If more animals were available, two additional groups were included: 6) closantel, and 7) moxidectin. The faecal egg count reduction test (FECRT) was carried out to evaluate the pre- and post-treatment using the SHINY tool. Haemonchus spp. was the most prevalent nematode from faecal cultures. The mean efficacy of albendazole was 40%. Only in two farms, levamisole presented a relatively high percentage of reduction in the FECRT about 90%, while ivermectin and moxidectin presented the worst mean efficacy of 34% and 21% among all farms, respectively. Like other anthelmintics, closantel demonstrated low efficacy (63%) across all farms evaluated. Monepantel presented an overall mean efficacy of 79%, but it was the only anthelmintic that presented efficacy ≥95%, in five farms. The results revealed that gastrointestinal nematodes with multiple anthelmintic resistance were prevalent in all 15 sheep herds. The research suggests that nematodes are becoming more and more resistant to various anthelmintic compounds, which has made the problem worse. This circumstance highlights the necessity to put into practice sustainable and long-lasting methods to prevent gastrointestinal nematode infections in sheep husbandry.

Summary: Background: Oncoplastic surgery has been increasingly used in breast cancer treatment and allows the performance of breast-conserving surgery in cases of larger tumors with unfavorable location or tumor-breast disproportion. Purpose: To compare surgical and oncological outcomes of patients undergoing oncoplastic and nononcoplastic breast-conserving surgery. Methods: Retrospective cohort study with convenience sampling of 866 patients who consecutively underwent breast-conserving surgery from 2011 to 2015. Results: The mean follow-up was 50.4 months. Nononcoplastic breast conservation surgery was performed on 768 (88.7%) patients and oncoplastic surgery on 98 (11.3%) patients. Patients in the oncoplastic group were younger (p2 cm (p

OBJETIVO: O objetivo deste trabalho foi avaliar a influência da reconstrução mamária imediata com a técnica de rotação de retalho miocutâneo pediculado do músculo reto abdominal, no prognóstico de pacientes portadoras de câncer de mama localmente avançado. PACIENTES E MÉTODOS: Foram selecionadas no ambulatório de patologia mamária do Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas, no período de junho de 1982 a junho de 1989, 45 pacientes com câncer de mama estádio IIIa submetidas à mastectomia radical com reconstrução imediata e comparadas com um grupo-controle de 45 pacientes com câncer de mama estádio IIIa submetidas apenas à mastectomia radical. Os parâmetros estudados foram: intervalo livre de doença local, intervalo livre de doença à distância e sobrevida total. RESULTADOS: A taxa de recidiva local foi baixa, sendo 6,6% no grupo de estudo e 4,4% no grupo-controle. Em relação à curva de sobrevida livre de doença local, não houve diferenças significativas entre o grupo tratado com MRRI e o grupo tratado com MR. Em relação à taxa de recidiva à distância os resultados foram semelhantes nos dois grupos. A curva de sobrevida livre de doença à distância não mostra diferenças significativas. Verificou-se que as recidivas ocorreram homogeneamente durante os primeiros 5 anos pós-mastectomia nos dois grupos. A sobrevida total foi praticamente a mesma nos dois grupos. A curva de sobrevida total não mostra diferenças significativas entre o grupo de casos e os controles. CONCLUSÃO: Concluiu-se que não houve interferência da reconstrução imediata nos parâmetros estudados.

The capture and separation of carbon dioxide (CO2) has been the focus of a plethora of research in order to mitigate its emissions and contribute to global development. Given that CO2 is commonly found in natural gas streams, there have been efforts to seek more efficient materials to separate gaseous mixtures such as CO2/CH4. However, there are only a few reports regarding adsorption processes within pressurized systems. In the offshore scenario, natural gas streams still exhibit high moisture content, necessitating a greater understanding of processes in moist systems. In this article, a metal-organic framework synthesis based on zirconium (MOF-808) was carried out through a conventional solvothermal method and autoclave for the adsorption of CO2 and CH4 under different temperatures (45–65 °C) and pressures up to 100 bar. Furthermore, the adsorption of humid CO2 was evaluated using thermal analyses. The MOF-808 synthesized in autoclave showed a high surface area (1502 m2/g), a high capacity for CO2 adsorption at 50 bar and 45 °C and had a low selectivity to capture CH4 molecules. It also exhibited a fine stability after five cycles of CO2 adsorption and desorption at 50 bar and 45 °C − as confirmed by structural post-adsorption analyses while maintaining its adsorption capacity and crystallinity. Furthermore, it can be observed that the adsorption capacity increased in a humid environment, and that the adsorbent remained stable after adsorption cycles in the presence of moisture. Finally, it was possible to confirm the occurrence of physisorption processes through nuclear magnetic resonance (NMR) analyses, thus validating the choice of mild temperatures for regeneration and contributing to the reduction of energy consumption in processing plants.

Precise and efficient insertion of large DNA fragments into somatic cells using gene editing technologies to label or modify endogenous proteins remains challenging. Non-specific insertions/deletions (INDELs) resulting from the non-homologous end joining pathway make the process error-prone. Further, the insert is not readily removable. Here, we describe a method called CRISPR-mediated insertion of exon (CRISPIE) that can precisely and reversibly label endogenous proteins using CRISPR/Cas9-based editing. CRISPIE inserts a designer donor module, which consists of an exon encoding the protein sequence flanked by intron sequences, into an intronic location in the target gene. INDELs at the insertion junction will be spliced out, leaving mRNAs nearly error-free. We used CRISPIE to fluorescently label endogenous proteins in mammalian neurons in vivo with previously unachieved efficiency. We demonstrate that this method is broadly applicable, and that the insert can be readily removed later. CRISPIE permits protein sequence insertion with high fidelity, efficiency, and flexibility.

This study examined the relationships between vertical jump asymmetries and speed and power performance in elite female soccer athletes. Sixteen professional female soccer players (age: 23.0 ± 3.8 years; body mass: 60.2 ± 7.3 kg; height: 165.1 ± 5.5 cm) from the same professional club participated in this study. Athletes performed unilateral and bilateral squat jumps (SJ) and countermovement jumps (CMJ) on a portable force plate; 30-m sprinting test; Zigzag change-of-direction (COD) test; and muscle power testing using the jump squat (JS) exercise. Asymmetry scores were obtained from the results of the unilateral SJ and CMJ by the percentage difference between the dominant and non-dominant legs. The Pearson product-moment coefficient of correlation was used to analyse the correlations between the bilateral and unilateral vertical jump variables and the physical tests. The bilateral vertical jump performance (in both SJ and CMJ) was closely related to sprinting and JS power performances (r values ranging from 0.50 to 0.73; P< 0.05). In contrast, no significant associations were found between jump asymmetries and performance measures. Our data suggest that asymmetry scores derived from unilateral vertical jumps are not capable of influencing the speed-power performance of professional female soccer players.

Exposure to loud sounds is related to harmful mental and systemic effects. The hippocampal function can be affected to either high-intensity sound exposure or long-term sound deprivation. We previously showed that hippocampal long-term potentiation (LTP) is inhibited after ten days of daily exposure to 2 minutes of high-intensity noise (110 dB), in the hippocampi of Wistar rats. Here we investigated how the glutamatergic and GABAergic neurotransmission mediated by ionotropic receptors is affected by the same protocol of high-intensity sound exposure. We found that while the glutamatergic transmission both by AMPA/kainate and NMDA receptors in the Schaffer-CA1 synapses is unaffected by long-term exposure to high-intensity sound, the amplitude of the inhibitory GABAergic currents is potentiated, but not the frequency of both spontaneous and miniature currents. We conclude that after prolonged exposure to short periods of high-intensity sound, GABAergic transmission is potentiated in the hippocampal CA1 pyramidal neurons. This effect could be an essential factor for the reduced LTP in the hippocampi of these animals after high-intensity sound exposure. We conclude that prolonged exposure to high- intensity sound could affect hippocampal inhibitory transmission and consequently, its function.

Introduction. Dry eye is one of the most frequent eye problems with prevalence and incidence from 5% to 50%. Citation network analysis allows us to simplify information in a visual way and provides a better understanding of the research done in a specific field. The objective of this paper is to quantify and analyse the relationships among the scientific literature in this field using citation network analysis. Materials and Methods. The program used to analyse the citations was CitNetExplorer®. Previously, papers published in the research field during a predefined period were found using the keywords defined in Web of ScienceTM (WOS). Results. Using the keyword “dry eye,” during the period 2007 to 2018, the most cited paper is by Lemp, MA (2007), with a citation index score of 913 in our citation network containing 6,500 most relevant papers. Analysing clustering, we found 5 relevant groups that match the main areas of research in this field: definition and classification, treatment, retina, refractive surgery, and quality of vision. Core Publication is composed of 64% of the papers in the network, which is a high percentage. It indicates a clear focus on the research carried out in this field. Conclusions. This citation network analysis shows definition and classification of dry eye to be the most researched area in this field, followed by treatment.

Objective. To analyse the prevalence of myopia among a sample of more than 6000 children in Spain as well as to determine the impact of risk factors in its progression. Methodology. A total of 6,152 children aged from 5 to 7 were examined. The participants underwent an eye examination that included visual acuity, refraction without cycloplegia, and tests of accommodative and binocular function. In addition, a questionnaire regarding their lifestyle, family history, and geographical data was carried out. Finally, data were analysed using the SPSS version 25 program. Results. The prevalence of myopia in the sample of children studied has increased from 17% in 2016 to 20% in 2017. Likewise, the number of children with high myopia has also increased, from 1.7% in 2016 to 3.6% in 2017. 43.3% of the participants spent more than 3 hours a day doing near activities, and 48.9% of this group spent more than 50% of this time using electronic devices. In addition, only 9.7% spent more than 2.5 hours outdoors each day. Conclusion. Myopia prevalence appears to be increasing in Spain. Lifestyle factors appear to be increasing the risk of myopia.

The aim of this study was to compare the effects of two different mixed training programs (optimum power load [OPL] + resisted sprints [RS] and OPL + vertical/horizontal plyometrics [PL]) on neuromuscular performance of elite soccer players during a short-term training preseason. Eighteen male professional soccer players took part in this study. The athletes were pair-matched in two training groups: OPL + RS and OPL + PL. Unloaded and resisted sprinting speeds at 5-, 10-, 20-, and 30-m, change of direction (COD) speed, and performance in the squat jump (SJ), countermovement jump (CMJ), and horizontal jump (HJ) were assessed pre- and post- a 5-week training period. Magnitude based inference with the effect sizes were used for data analysis. A possible increase in the SJ and CMJ heights and a likely increase in the HJ distance were observed in the OPL + PL group. Meaningful improvements were observed in the COD speed test for both training groups comparing pre- and post-measures. In both unloaded and resisted sprints, meaningful decreases were observed in the sprinting times for all distances tested. This study shows that a mixed training approach which comprises exercises and workloads able to produce positive adaptations in different phases of sprinting can be a very effective strategy in professional soccer players. Moreover, the possibility of combining optimum power loads with resisted sprints and plyometrics emerges as a novel and suitable option for coaches and sport scientists, due to the applicability and efficiency of this strength-power training approach.

Einsteins general theory of relativity from 19151 remains the most successful description of gravitation. From the 1919 solar eclipse2 to the observation of gravitational waves3, the theory has passed many crucial experimental tests. However, the evolving concepts of dark matter and dark energy illustrate that there is much to be learned about the gravitating content of the universe. Singularities in the general theory of relativity and the lack of a quantum theory of gravity suggest that our picture is incomplete. It is thus prudent to explore gravity in exotic physical systems. Antimatter was unknown to Einstein in 1915. Diracs theory4 appeared in 1928; the positron was observed5 in 1932. There has since been much speculation about gravity and antimatter. The theoretical consensus is that any laboratory mass must be attracted6 by the Earth, although some authors have considered the cosmological consequences if antimatter should be repelled by matter7-10. In the general theory of relativity, the weak equivalence principle (WEP) requires that all masses react identically to gravity, independent of their internal structure. Here we show that antihydrogen atoms, released from magnetic confinement in the ALPHA-g apparatus, behave in a way consistent with gravitational attraction to the Earth. Repulsive antigravity is ruled out in this case. This experiment paves the way for precision studies of the magnitude of the gravitational acceleration between anti-atoms and the Earth to test the WEP.

This research’s objective was to determine the dietary rumen degradability and growth performances of goats fed dietary treatments. 18 native female goats (live weight of 7.96 ± 2.21 kg) were grouped into 6 classes for the feeding trial and 3 male mature goats with rumen cannula were used for the in situ digestibility. The three dietary treatments were: T1 - 72:28 Forage-Concentrate NDF ratio; T2 - 64:36; and T3 - 57:43. The rate of rumen degradability of DM and CP at 0 hours, potentially degradable fraction (b) and the rate of degradation of b were not affected by dietary treatments. The different ratios of NDF in the diets significantly affected the intake of DM, CP and NDF from forage and concentrates. Treatment diets affected the total intake of DM, CP and NDF of the animals. However, growth performance was not affected by the treatments showing the same production efficiency. This means that diets given to native goats with ratio of forage NDF of 72.07% can be applied since the value of the output and efficiency of feed utilization had the same value compared to diets ratio of forage NDF of 57.21%.

Tephrosia toxicaria, which is currently known as Tephrosia sinapou (Buc’hoz) A. Chev. (Fabaceae), is a source of compounds such as flavonoids. T. sinapou has been used in Amazonian countries traditional medicine to alleviate pain and inflammation. The purpose of this study was to evaluate the analgesic effects of T. sinapou ethyl acetate extract in overt pain-like behavior models in mice by using writhing response and flinching/licking tests. We demonstrated in this study that T. sinapou extract inhibited, in a dose (1–100 mg/kg) dependent manner, acetic acid- and phenyl-p-benzoquinone- (PBQ-) induced writhing response. Furthermore, it was active via intraperitoneal, subcutaneous, and peroral routes of administration. T. sinapou extract also inhibited formalin- and complete Freund’s adjuvant- (CFA-) induced flinching/licking at 100 mg/kg dose. In conclusion, these findings demonstrate that T. sinapou ethyl acetate extract reduces inflammatory pain in the acetic acid, PBQ, formalin, and CFA models of overt pain-like behavior. Therefore, the potential of analgesic activity of T. sinapou indicates that it deserves further investigation.

This study aimed to examine the associations between a series of mechanical variables automatically generated by a portable force plate (PFP) and the actual performance of professional sprinters over a 150 m course. To test these correlations, 12 top-level sprinters performed vertical jumps (squat and countermovement jumps; SJ and CMJ, respectively), a 60 m sprint test, and a 150 m sprint test. Pearson product-moment coefficient of correlation and multiple regression analyses were used to determine the relationships between the sprinting velocities and vertical jump outputs. The SJ parameters were moderately to near perfectly associated with the different sprint distances, and the SJ height presented the highest correlation scores (r = 0.90 with velocities over 10- and 20-m). The correlation coefficients between the CMJ outcomes and sprint results varied between moderate and very large (from 0.38 to 0.88). Finally, the coefficients of determination (R2) ranged from 0.71 to 0.85 for the different multiple regressions involving PFP automatic measures. The PFP can provide practitioners with quick and accurate information regarding competitive athletes. Due to the strong correlations observed, coaches are encouraged to frequently adjust and tailor the training strategies of their sprinters, using practical and timesaving PFP measurements.

Microesferas de quitosana podem ser empregadas na área de biomaterias, em processos biotecnológicos e como adsorventes. Neste trabalho, foi empregada a técnica de atomização e coagulação para produção dessas microesferas, que permitiu o controle dos parâmetros de operação e por conseqüência a obtenção de microesferas de tamanho e faixas de tamanho específicos. Após a sua obtenção, as microesferas foram modificadas quimicamente com objetivo de estudar as resistências térmica, mecânica e química. Para isso foram empregadas três rotas distintas: a-) reticulação com glutaraldeído; b-) reticulação com epicloridrina e c-) acetilação. As microesferas preparadas apresentaram distribuição de tamanho da ordem de 140 µm com desvio padrão de 11,9 µm. Após as modificações químicas, as microesferas apresentaram temperatura de degradação térmica em torno de 300 ºC, aumento da estabilidade química à solução de HCl, e diminuição da resistência mecânica.Chitosan microspheres can be used as biomaterial, in biotechnology processes and as adsorbents. This work is concerned with the production of chitosan microspheres using spraying and coagulation processes, which allows us to control the operating parameters and to produce chitosan microspheres of several ranges and sizes. The microspheres were modified chemically in order to study their thermal, mechanical and chemical resistance. The methods used were: 1) crosslinking with glutaraldehyde; 2) crosslinking with epichlorohydrin; 3) acetylation. The microspheres obtained presented mean particle size of 140 µm and standard deviation of 11.9 µm. The modified microspheres showed thermal degradation around 300 ºC, an increase of chemical stability using HCl solution and a decrease of mechanical resistance.

Neste trabalho foi realizado um estudo de avaliação da degradação "in vitro" da blenda biorreabsorvível poli(beta-hidroxibutirato) (PHB) / poli(L-ácido lático) (PLLA). As blendas PHB/PLLA na forma de filmes, nas composições 0/100, 30/70, 50/50, 70/30 e 100/0 (% em massa), foram obtidas pelo método de evaporação do solvente. Os filmes obtidos foram imersos em solução tampão fosfato salino, PBS, (pH 7,4) por 12 meses em banho termostatizado à 37 °C. As amostras foram caracterizadas por MDSC, TG, DMA, SEM, WAXS e SAXS, antes e após o processo de degradação. Os resultados mostraram que a blenda PHB/PLLA é imiscível em todas as composições estudadas, apresentando morfologia com separação de fases. Observou-se que o PLLA perdeu propriedades mecânicas de tração mais rapidamente que o PHB, durante o processo de degradação, tornando-se mais quebradiço. Verificou-se também aumento no grau de cristalinidade e na espessura do período longo das cadeias poliméricas nas blendas em função da degradação, sugerindo aumento da lamela cristalina.In this work, "in vitro" degradation of poly(beta-hydroxybutyrate) (PHB) / poly(L-lactic acid) (PLLA) blends was evaluated. Films of PHB/PLLA blends, in the compositions 0/100, 30/70, 50/50, 70/30 and 100/0 (% weight), were fabricated by casting. The films obtained were immersed in a phosphate buffer solution, PBS (pH 7.4) for 12 months. The samples were characterized by MDSC, TG, DMA, SEM, WAXS and SAXS, before and after the degradation process. The results showed that the PHB/PLLA blends are immiscible and present phase separation as indicated by microscopy. The PLLA loses mechanical properties faster than PHB, during the degradation process. It was observed that the blends increased their crystallinity degree and long period thickness as a function of degradation time.

The influence of the calcification solution on the mineralization of chitosan membranes was analysed. Two factors were studied: pH and chemical composition (excess of calcium or phosphate ions) of solutions. Substrates (membranes) of chitosan underwent mineralization by soaking in calcification solutions for 7 days at 36.5 °C. As expected, SEM-EDS analyses demonstrated that higher pH and concentration of ions increases deposition, however, the morphology and composition of these deposits varies depending on which ion (phosphate or calcium) is in excess. Larger spherical deposits are observed when a calcium-rich solution is used instead of a phosphate-rich one. In the latter, the interconnectivity of the inorganic and organic (matrix) phases is very different, suggesting a different mechanism of deposition for each situation.

O presente trabalho trata da preparação e caracterização de membranas de quitosana porosas e densas, que possuem diversas aplicações tecnológicas. Para tanto, foram utilizadas as técnicas de microscopia (microscopia eletrônica de varredura - MEV - e microscopia de força atômica -MFA), titulação potenciométrica e espectroscopia no infravermelho (FTIR-ATR). A síntese das estruturas foi realizada através da secagem total ou parcial de uma solução acética de quitosana a 2,5% (w/w) seguida de coagulação em meio alcalino. Glutaraldeído foi utilizado para modificar quimicamente as membranas, tornando-as mais hidrofóbicas. A extensão deste processo pôde ser observada por FTIR-ATR, utilizando-se um plano fatorial onde foram variados o tempo de fixação e a concentração de glutaraldeído na solução de tratamento.

The secnidazole, a drug used in hepatic amebiasis, giardiasis and bacterial vaginosis, was enantioseparated on a semi-preparative scale by high performance liquid chromatography (HPLC), using chiral stationary phase (CSP) containing amylose tris (3, 5-dimethylphenyl) carbamate on silica gel (Chiralpak® AD). The experiments were carried out under normal phase conditions and the separation method exhibited very high selectivity and resolutions. The chromatographic parameters and the effects of column temperature on the retention time and selectivity were evaluated. Thermodynamic parameters were obtained from van't Hoff plots, and the elution order of the enantiomers was determined by circular dichorism. The enantiomers of secnidazole were separated under overloaded conditions with a good performance.

While the potential of social networking sites to contribute to educational endeavors is highlighted by researchers and practitioners alike, empirical evidence on the use of such sites for formal online learning is scant. To fill this gap in the literature, we present a case study of learners’ perspectives and experiences in an online course taught using the Elgg online social network. Findings from this study indicate that learners enjoyed and appreciated both the social learning experience afforded by the online social network and supported one another in their learning, enhancing their own and other students’ experiences. Conversely, results also indicate that students limited their participation to course-related and graded activities, exhibiting little use of social networking and sharing. Additionally, learners needed support in managing the expanded amount of information available to them and devised strategies and “workarounds” to manage their time and participation.

BackgroundObesity has often been associated with severe allergic asthma (AA). Here, we analyzed the frequency of different circulating CD4+T-cell subsets from lean, overweight and obese AA patients.MethodsMononuclear cells from peripheral blood were obtained from 60 AA patients and the frequency of different CD4+T-cell subsets and type 1 regulatory B cells (Br1) was determined by cytometry. The effect of obese-related leptin dose on cytokine production and Treg cell function in AA-derived CD4+ T cell cultures was evaluated by ELISA and 3H thymidine uptake, respectively. Leptin levels were quantified in the plasma by ELISA. According to the BMI, patients were stratified as lean, overweight and obese.ResultsAA severity, mainly among obese patients, was associated with an expansion of hybrid Th2/Th17 and Th17-like cells rather than classic Th2-like cells. On the other hand, the frequencies of Th1-like, Br1 cells and regulatory CD4+ T-cell subsets were lower in patients with severe AA. While percentages of the hybrid Th2/Th17 phenotype and Th17-like cells positively correlated with leptin levels, the frequencies of regulatory CD4+ T-cell subsets and Br1 cells negatively correlated with this adipokine. Interestingly, the obesity-related leptin dose not only elevated Th2 and Th17 cytokine levels, but also directly reduced the Treg function in CD4+ T cell cultures from lean AA patients.ConclusionIn summary, our results indicated that obesity might increase AA severity by favoring the expansion of Th17-like and Th2/Th17 cells and decreasing regulatory CD4+T cell subsets, being adverse effects probably mediated by leptin overproduction.

Due to a world-wide health emergency, higher education instructors were compelled to adapt their courses from traditional in-person classes to remote learning. In this case study, we investigated the use of flipped learning for this adaptation process from diverse higher education instructors' perspectives. To mitigate social distancing requirements, instructors included synchronous and asynchronous components in using the flipped approach to their courses. The use of video conferencing synchronous sessions to replace the in-person class time showed a nuanced approach to flipped learning that required exploration. Instructors from distinct academic settings were interviewed on their experience in using the flipped approach in their courses adapted for maintaining social distancing protocol. Using case methodology, nine instructors from various locations and disciplines were interviewed on how they transformed their courses utilizing flipped approaches. Findings from the interview texts showed the distinction of asynchronous and synchronous elements, as key components of fully online flipped learning environments. Findings in this study highlights the importance of supporting student engagement for autonomous learning in courses using online flipped learning approaches. Implications for the support of student self-determined learning through the implementation of synchronous and asynchronous learning components are discussed.

The influence of temperature on the equilibrium and mass-transfer parameters in the chromatographic separation of bupivacaine enantiomers was evaluated using a chiral stationary phase (CSP) based on diallyl-L-tartardiamide (Kromasil® CHI-TBB). The total and bed porosities as well as the linear equilibrium constant were obtained by pulse experiments using dilute solutions of inert compounds and bupivacaine enantiomers at different flow rates (1.0, 2.0, 3.0 and 4.0 m l /min) and temperatures (25, 35 and 45°C). The axial dispersion and overall mass-transfer coefficients were evaluated by van Deemter plot. A decrease in the linear equilibrium adsorption constants with increasing temperature was observed for both enantiomers. This chiral column showed good separation performance with a high order of magnitude for the overall mass-transfer coefficient. These values increased with increasing temperature. However, it was not possible to differentiate between these values at different temperatures due to poor standard deviations. Because of the high order of magnitude of the overall mass-transfer coefficient associated with a good resolution of bupivacaine enantiomers, it was concluded that convection effects dominated chiral separation in this column.