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Retinal photography was performed in pregnancy and postpartum in pregnant Hispanic women with latent Toxoplasma gondii (TG) infection in order to screen for characteristic retinal lesions or the particular scars found in people with active T. gondii infection. A comparison group of TG negative women was included in the study but they did not have retinal photography. The goal of the parent study was to assess for adverse pregnancy events and evidence for parasite reactivation in TG positive (TG +) women, through examination of the eyes for characteristic lesions. Retinal photography, usually at prenatal visits 2 (17 +/- 3.35 weeks) and 3 (26.3+/-1.75) weeks, was done on TG + women. Fifty-six of these women also (43 %) had retinal photography at the postpartum visit. Health and demographic data were obtained at the first prenatal visit for all women. From the 690 recruited at the first prenatal visit, 128 TG – women and 158 TG + women were enrolled in a prospective study through pregnancy and the postpartum. All TG- women (n = 532) provided data at the first prenatal visit and throughout their pregnancy and birth through the EHR. This allowed comparison of health and outcome data for the TG + compared to a larger number of TG- Hispanic pregnant women. While there was no evidence of ocular toxoplasmosis during pregnancy, there was a surprisingly large number (42 %) of TG + women with diabetic retinopathy (DR). We also observed that TG + women had a 20 % incidence of gestational diabetes mellitus (GDM) compared to 11.3 % in the TG- women (p = 0.01). At postpartum (mean 5.6 weeks), 23 of 30 women with pregnancy DR showed no DR in the postpartum. No characteristic T. gondii lesions were discovered. Retinal photography serendipitously revealed DR in these T. gondii positive women. It was also found that latent TG infection was associated with increased incidence of GDM. Hispanic pregnant women's increased risk for latent TG infection, GDM and DR are underappreciated. Retinal photography may need to be considered an innovative approach to screening. [ABSTRACT FROM AUTHOR]

Voluntary intake of cold fluid is greater than warm fluid as a result of more favorable palatability, resulting in better maintenance of hydration status and improved exercise performance. It remains unclear whether voluntary ingestion of ice slurry beverages compared with cold fluid during exercise yields superior results. Eight recreationally active subjects (mean ± SD; age = 24 ± 4 years, height = 175.2 ± 7.8 cm, mass = 79.6 ± 11.2 kg, body fat = 13.0 ± 5.2%) completed a pretest in 22° C to determine maximal workload (Wmax). Then, in 2, separate, counterbalanced trials, they cycled for 60 minutes at 50%Wmax in 35° C and 40% relative humidity with either ad libitum ice slurry (-1.3 ± 0.3° C) or cold fluid (11.1 ± 2.4° C) ingestion. This was immediately followed by a 15-minute cycling time trial. Subjects avoided 2% body mass loss in both conditions but ingested twice as much cold fluid as ice slurry (fluid: 1,074.7 ± 442.1 g, ice slurry: 526.9 ± 214.1 g; p = 0.001). Nonetheless, neither 15-minute performances (cold fluid: 119.5 ± 34.8 kJ, ice slurry: 114.6 ± 20.9 kJ; p = 0.59) nor whole-body sweat rates (fluid: 1,370 ± 311 ml·h-1, ice slurry: 1,242 ± 191 ml·h-1; p = 0.20) were different between the conditions. Despite ingesting half as much ice slurry as cold fluid, subjects experienced similar physiological responses and thus had similar performances under heat stress while avoiding excessive hypohydration. Under the conditions of this study, ice slurry ingestion was an effective alternative form of exercise hydration. [ABSTRACT FROM AUTHOR]

An emerging body of evidence suggests a causal relationship between wellbeing and incumbent voting. However, the evidence is primarily founded upon established democracies with regular turnovers of power. Moreover, the mechanism underlying this relationship is still relatively unknown. Using the intricacies of the Malaysian political context and Malaysian data from the seventh wave of the World Values Survey (WVS), this study examines the mediating role of trust in government to explain the relationship between life satisfaction and incumbent voting. Notably, the Malaysian WVS was concluded two weeks before Malaysia's fourteenth general election (GE14), which witnessed the end of the ruling coalition's six-decade hold on power since independence and subsequently ushered in the country's first-ever peaceful transfer of power. The empirical analysis indicated that the mediating role of trust in the relationship between life satisfaction and incumbent voting is supported. Further empirical analysis also showed that the mediating effect of trust was unique to the GE14 context compared to GE13, thus providing a better understanding of the role trust plays in the outcome of the election. The results provide valuable insights and implications in political science, especially for a nation emerging from its authoritarian state. [ABSTRACT FROM AUTHOR]

Background: As the vaccination drive against the coronavirus disease (COVID-19) in Malaysia progresses rapidly, the main challenge will gradually shift from procuring and distributing vaccines to ensuring the broadest possible acceptance among all population segments. Therefore, this study used the integrated framework of the health belief model (HBM) and the theory of reasoned action (TRA) to investigate the predictors of intention to receive COVID-19 vaccines in Malaysia. Methodology: A market research company in Malaysia was engaged to collect data during June 11–20, 2021 using self-administered questionnaires via its online panel, ensuring a nationwide random sample of 804 respondents. A logistic regression was subsequently estimated to determine the significant predictors of vaccination intention. Results: The predictors that significantly affect COVID-19 vaccine hesitancy in Malaysia are age, susceptibility, religious beliefs, attitude, subjective norms, and trust in the vaccine. In particular, those who are more inclined to get vaccinated are older individuals, have a higher perceived risk of infection and social pressure to get vaccinated, have a positive attitude, and have high levels of trust in the vaccine. Individuals' who perceive that their religious beliefs are against vaccination are more likely to exhibit uncertainty toward it. Conclusion: This study showed that although a large proportion of respondents indicated that they were willing to be vaccinated against COVID-19, there are concerns about religious barriers and trust in the vaccine that the relevant stakeholders should address. Campaigns should also focus on shaping the nation's attitude toward COVID-19 vaccines, in parallel with encouraging people to use their social influence in helping those in their close circle who are unsure of vaccination to cross the line. These measures will prove to be pertinent as the nation begins to administer booster vaccines to tackle the waning effects of COVID-19 vaccines. [ABSTRACT FROM AUTHOR]

A scoring criterion of three-or-more letters correct on a line results in the most equivalent visual acuity score to letter-by-letter scoring. Using the criterion of three-or-more letters correct on a line of five letters to measure a line visual acuity is common. In this study, different line acuity criteria are compared to letter-by-letter visual acuity scoring to determine which criterion is the most accurate as well as least variable. One eye each of 32 subjects was tested with high-contrast visual acuity charts at 4.88 m. Subjects had 16 acuities measured: 8 under normal conditions and 8 under a + 1.50D blur condition. For each set of 8, logMAR visual acuity results were obtained by retrospectively applying each of four scoring criteria twice: letter-by-letter acuity and three line acuities (three-or-more, four-or-more, or five correct on a line). Differences in means were analysed using repeated measures ANOVA with post-hoc Tukey testing. Test-retest variability was analysed via Bland-Altman analysis The mean visual acuities (in logMAR) were −0.10, −0.11, −0.07, and −0.01 for letter-by-letter, three-or-more correct, four-or-more correct, and all five correct, respectively. With blur, the mean visual acuities were 0.41, 0.39, 0.45, and 0.53 for the respective criteria. Under both normal and blur conditions, the different acuity scoring criteria resulted in significant differences (p < 0.001), except for the letter-by-letter and three-or-more criteria (p ≥ 0.18). Whereas the criteria resulted in similar test-retest variability under blur, the line acuity using a criterion of three-or-more letters correct resulted in the lowest test-retest variability under best-corrected conditions. A line visual acuity scoring criterion of three-or-more letters correct on a line, whether with good visual acuity or poorer visual acuity due to defocus, provides the most similar acuity and test-retest variability compared to letter-by-letter visual acuity. [ABSTRACT FROM AUTHOR]

Background: The Farnsworth-Munsell 100-hue test (FM100-hue) is a color-arrangement test wherein a patient must arrange 85 caps into color order. It is a well-known and widely accepted test, but it is not often used in primary eye care practice because it takes a fairly long time (about 10 minutes) to administer. However, this case report will show the usefulness of the test where other tests of color vision were not able to give a clear picture of a patient's color vision issue. Case Report: A 17-year-old Caucasian female presented with a complaint of having trouble distinguishing different shades of similar colors. The patient had a comprehensive eye exam a week prior to this visit, which did not reveal any significant findings. No family history of color vision deficiency was reported. She passed all color vision screening book tests. Additional tests, including the Farnsworth D15, were passed, but with some anomalies. The FM100-hue test was definitively failed and showed a severe (total error score = 372), non-specific color vision issue with errors in every part of the color circle. The patient was diagnosed as likely having genetically normal color vision, but with very poor hue discrimination. Conclusion: The case shows that the FM100-hue test can identify non-specific color vision issues, even when other color vision tests cannot, and the test has utility in clinical practice. [ABSTRACT FROM AUTHOR]

Background: Reverse high-contrast (white-onblack) visual acuity has been shown to improve visual acuity in older patients and patients with pathology under photopic testing. In this study, we investigated whether reverse contrast results in improved visual acuity at mesopic light levels. Methods: Monocular visual acuities (logMAR) were assessed at four different light levels (1 photopic {94 cd/m2} and 3 mesopic {3 cd/m2, 0.75 cd/m2, and 0.38 cd/m2}) in 47 visually normal subjects (27.4±9.3 years). Visual acuity was assessed using an E-ETDRS algorithm, in standard and reverse contrast, at 3 m. Repeated measures ANOVA with post-hoc Tukey testing was used to analyze the data across the light levels. Results: The mean standard contrast visual acuity was -0.07±0.06 under the photopic condition, 0.06±0.08 at 3 cd/m2, 0.17±0.08 at 0.75 cd/m2, and 0.28±0.09 at 0.38 cd/m2. For reverse contrast, it was -0.08±0.06 under the photopic condition, 0.01±0.07 at 3 cd/m2, 0.12±0.08 at 0.75 cd/m2, and 0.22±0.09 at 0.38 cd/m2. There was a significant improvement in visual acuity using reverse contrast under all mesopic light levels (p<0.001), but not under photopic conditions (p=0.15). Conclusions: At mesopic light levels, there were significant differences between standard and reverse contrast. The use of mesopic reverse-contrast visual acuity could be another way to detect subtle changes in visual acuity. Reversecontrast presentations under low lighting conditions may be advantageous for a patient's visual acuity. [ABSTRACT FROM AUTHOR]

This article focuses on identifying the variable which has the highest predictive power in predicting electoral behaviour. To do this, we apply a tree-based machine learning technique to data from Malaysia's 14th General Election. We find that constituencies' urbanization level has the most significant predictive power in determining vote share. Ethnicity, a long-touted variable of significance, plays a secondary role. Moreover, these predictors' marginal effects on the vote share are highly complex, non-linear and difficult to pick up by conventional regression [End Page 461] methods. Other explanatory factors do not exhibit significant predictive qualities of electoral behaviour, although the extant literature has shown them to have important causal relationships. As our analysis reflects the significant predictive power of urbanization in predicting voting behaviour, we caution against the haste to dismiss its relevance in the Malaysian context. [ABSTRACT FROM AUTHOR]

Background: In recent years, ketamine and esketamine treatment have demonstrated rapid antidepressant effects in adults with treatment-resistant depression (TRD). Hitherto, relatively few studies have reported the effect of ketamine/esketamine treatment on functional outcomes (e.g., psychosocial functioning, workplace functioning). Herein, we review and synthesize extant literature reporting functional outcomes with ketamine/esketamine treatment in adults with TRD.Methods: A systematic review of clinical studies reporting subjective or objective ratings of general functioning as primary or secondary outcomes was performed.Results: Four randomized-controlled trials, one open-label clinical study and one case series reported on the efficacy of ketamine/esketamine on subjective measures of general functioning. Overall, mixed results were reported with respect to the effect across disparate functional measures (e.g., Sheehan Disability Scale [SDS]) using ketamine/esketamine. A single study demonstrated a significant decrease (i.e., improvement) in SDS total scores in TRD with esketamine treatment; most studies, however, did not report on functional outcomes and have functional outcomes as a (co)-primary outcome measure.Limitations: Clinical studies that were included evaluated work- or social-related disability as a secondary outcome using subjective rating scales.Conclusion: Functional outcomes in adults with TRD receiving ketamine/esketamine was insufficiently characterized. Available evidence indicates that improvements in general psychosocial functioning is apparent. The association, if any, between symptomatic improvement and functional improvement in TRD, as well as the temporality to improve functioning, are future research vistas. [ABSTRACT FROM AUTHOR]

Background: The Lanthony desaturated color vision test is a color arrangement test wherein a patient must arrange 15 caps into color order. It is a difficult test for color-normal patients and is even more challenging for color vision-deficient patients due to its low saturation, which makes the cap-color differences fairly small. Despite the challenge, this case report will show that the test may not always be reliable. Case Report: A 25-year-old Caucasian male returned to our office for continued evaluation for color vision deficiency. He had previously been diagnosed with protanopia based on anomaloscope testing, which was consistent with other color tests. The patient had previously shown learning on the easier Farnsworth saturated color test and was interested in attempting to learn a harder test. The patient was sent home with a Lanthony color test and Richmond Illuminator. He returned for follow-up testing, which showed that he was able to score perfectly on the Lanthony desaturated color test, which was very surprising. Conclusion: This case shows that for some highly motivated patients, the Lanthony D15 color test may be subverted, and knowledge of this possibility is important for clinicians to consider. [ABSTRACT FROM AUTHOR]

Background: Several validated, age-specific recognition visual acuity measurement charts used in research and vision screenings follow national and international guidelines for standardized eye charts. The Kindergarten (aka Sailboat) chart is widely used to measure visual acuity in children, but no literature has evaluated its accuracy. This study evaluates the chart against a validated chart. Methods: School children (n = 51, 42% female, 58% male) were recruited from El Monte, California. The mean age of the participants was 5.7 years (SD = 1.7 years). Visual acuities were assessed with Lea symbols, a validated chart, and the Kindergarten chart on one randomized eye per child. Acuities (converted to logMAR) were recorded using the letter-by-letter method. Data were analyzed using letter-by-letter and line-by-line scoring (≥50% on a line) using 2-tailed paired t-tests and Bland-Altman analysis, including 95% limits of agreement (LOA). Results: Mean (±SD) logMAR acuities for the Lea symbols chart were 0.15 ± 0.16 and 0.14 ± 0.17 for letter-by-letter and line-by-line methods, respectively. For the Kindergarten chart, it was 0.25 ± 0.20 for both methods. The approximate 1-line difference between the charts using either scoring method was significantly different (p < 0.001). The 95% LOAs were ±0.28 for both scoring methods. Conclusions: The Kindergarten chart resulted in a visual acuity approximately one line worse than the chart using Lea symbols. The Kindergarten chart had poor agreement with the chart using Lea symbols. Clinicians using the Kindergarten chart should be cautious in interpreting the recorded visual acuity, as this could lead to false positives and subsequent over-referral of children. It would be more prudent simply to discontinue using the Kindergarten chart, especially when much better visual acuity charts for children are readily available. [ABSTRACT FROM AUTHOR]

The 14th Malaysian general elections (GE14) resulted in a regime change not experienced since independence. While ethnicity has been an overriding factor in determining electoral outcomes, urbanization has recently been considered a competing factor that might weaken the effects of ethnicity. Using a new methodology to model the compositional effects of ethnicity, we analyse the effects of both factors on the GE14 in our regression models. The findings show that both ethnicity and urban development do affect electoral outcomes, with ethnicity being the more dominant factor. Additionally, multivariate results show that neither malapportionment nor redelineation explains electoral outcomes. We provide a dissection of the 'Malaysian tsunami' examining vote change patterns between GE13 and GE14 using an ethnic and rural-urban continuum. The analysis reveals that effects of the tsunami are not evenly spread across ethnic groups and geographical regions, with the Malay majority and ethnically mixed seats displaying contrasting voting patterns. [ABSTRACT FROM AUTHOR]

Intravenous (IV) ketamine has been shown to have rapid and robust antidepressant effects in adults with treatment-resistant depression (TRD). Urological toxicity has been observed in chronic ketamine abusers as evidenced by dysuria, urgency, and hematuria. The foregoing observation provides the basis for evaluating whether ketamine-induced urological toxicity (KIUT) is associated with sub-anesthetic doses of ketamine (0.5–1.0 mg/kg) in adults with mood disorders. The overarching objective of this article is to identify potential mechanisms of KIUT which appears to be dose and frequency dependent. Available research indicates that high-frequency ketamine is associated with disruption of the urothelial barrier as well as direct ketamine toxicity (i.e., decreased expression of junction proteins) in KIUT of the bladder. Chronic and high-frequency ketamine use is also associated with bladder inflammation mediated via neurogenic and IgE inflammation. Other non-mutually exclusive causes are nerve hyperplasia, hypersensitivity, cell apoptosis, microvascular damage, and overexpression of carcinogenic genes. Notwithstanding the evidence of KIUT in ketamine abusers, there is no evidence that ketamine and/or esketamine treatment in adults with mood disorders is associated with KIUT. However, all patients receiving ketamine/esketamine for mood disorder treatment should be queried about genitourinary symptoms during acute and, where applicable, maintenance dosing. [ABSTRACT FROM AUTHOR]

Background: Vaccination has been one of the most effective preventive strategies to contain the COVID-19 pandemic. However, as the COVID-19 vaccines' effect wanes off after some time and given their reduced level of protection against mutation strains of the virus, the calls for boosters and second boosters signal the need for continuous vaccination for the foreseeable future. As Malaysia transitions into the endemic phase, the nation's ability to co-exist with the virus in the endemic phase will hinge on people's continuance intention to be vaccinated against the virus. Adapting the expectations confirmation model (ECM) to the public health context and in a developing country, this study integrates the ECM with the health belief model (HBM) and the theory of reasoned action (TRA) to examine the inter-relationships of the predictors of people's continuance intention to vaccinate against COVID-19. Methodology: Data were collected using self-administered questionnaires from 1,914 respondents aged 18 and above by a marketing consulting firm via its online panel. The partial least squares structural equation modeling (PLS-SEM) technique was used to analyze the data. Results: Out of the 1,914 respondents, 55.9% reported having a continuance intention to vaccinate against COVID-19, similar to other developing countries. The multivariate analysis revealed that perceived usefulness and satisfaction significantly influenced individuals' continuance intention to vaccinate against COVID-19. Additionally, attitude was found to play a key role in influencing behavioral change among individuals towards their perceptions of continuously getting vaccinated against COVID-19. Conclusions: By integrating three theoretical frameworks (i.e., HBM, TRA and ECM), this study showed that behavioral characteristics could provide insights towards continuance vaccination intention. Hence, policymakers and key stakeholders can develop effective public health strategies or interventions to encourage vaccine booster uptake by targeting behavioral factors such as perceived usefulness, attitude, satisfaction, and subjective norms. [ABSTRACT FROM AUTHOR]

The development of root nodules leads to an increased auxin response in early nodule primordia, which is mediated by changes in acropetal auxin transport in some legumes. Here, we investigated the role of root basipetal auxin transport during nodulation. Rhizobia inoculation significantly increased basipetal auxin transport in both Medicago truncatula and Lotus japonicus. In M. truncatula , this increase was dependent on functional Nod factor signalling through NFP , NIN , and NSP2 , as well as ethylene signalling through SKL. To test whether increased basipetal auxin transport is required for nodulation, we examined a loss-of-function mutant of the M. truncatula PIN2 gene. The Mtpin2 mutant exhibited a reduction in basipetal auxin transport and an agravitropic phenotype. Inoculation of Mtpin2 roots with rhizobia still led to a moderate increase in basipetal auxin transport, but the mutant nodulated normally. No clear differences in auxin response were observed during nodule development. Interestingly, inoculation of wild-type roots increased lateral root numbers, whereas inoculation of Mtpin2 mutants resulted in reduced lateral root numbers compared with uninoculated roots. We conclude that the MtPIN2 auxin transporter is involved in basipetal auxin transport, that its function is not essential for nodulation, but that it plays an important role in the control of lateral root development. [ABSTRACT FROM AUTHOR]

Cardiovascular (CV) drift, the progressive increase in heart rate (HR) and decrease in stroke volume (SV) during constant rate, moderate intensity exercise, is related to reduced maximal oxygen uptake (V̇O2max) during heat stress. Once it has already occurred, it is unknown whether the detrimental effects of CV drift on V̇O2max can be reversed. This study tested the hypothesis that fan cooling after CV drift has occurred attenuates decrements in V̇O2max associated with CV drift. Eight men completed a control graded exercise test (GXT) in 22°C to measure V̇O2max. Then on separate, counterbalanced occasions, they completed one 15-min (15MIN) and two 45-min bouts (45NF and 45FAN) of cycling in 35°C, 40% RH at 60% V̇O2max, each immediately followed by a GXT to measure V̇O2max. For one of the 45-min trials (45FAN), fan airflow (4.5 m/s) was directed at participants beginning ~5 min before the GXT and continuing throughout the remainder of exercise. The purpose of the separate 15- and 45-min trials was to measure V̇O2max during the same time interval that CV drift occurred. HR increased (13.8% and 11.4%) and SV decreased (14.4% and 14.1%) for 45NF and 45FAN, respectively; trials were not different (all P > 0.05). Despite a decrease in mean skin temperature of ~1°C with fan use, V̇O2max decreased similarly between conditions (17% vs. 15% for 45NF and 45FAN, P = 0.54). Fan cooling after CV drift was insufficient to reverse the negative consequences of CV drift on V̇O2max after prolonged exercise in a hot environment. Abbreviations: 15MIN: 15-min trial; 45FAN: 45-min, fan trial; 45NF: 45-min, no fan trial; ANOVA: Analysis of variance; CV: Cardiovascular; GXT: Graded exercise test; HR: Heart rate; SV: Stroke volume; T̅b: Mean body temperature; Tre: Rectal temperature; T̅sk: Mean skin temperature; V̇O2max: Maximal oxygen uptake [ABSTRACT FROM AUTHOR]

Purpose: Conflicting findings exist in the literature with regard to the relationship between iris color, ethnicity, macular pigment optical density (MPOD), and hue discrimination. This study re-examined these relationships, accounting for factors that may have confounded prior studies. Clinically, the relationship between MPOD and hue discrimination may impact the utility of macular pigment supplementation as a treatment for conditions such as macular degeneration. Methods: Subjects (n = 30, mean/SD age = 25.1/2.5 yrs.) with normal color vision completed MPOD testing and Farnsworth-Munsell 100 hue (FM100) testing. MPOD data was derived from the average of three measurements using the QuantifEYE II device and FM100 testing included training runs. The total error score of the FM100 test was used for analysis. Iris color was determined subjectively, while iris reflectance was derived using calibrated iris images. Spearman correlations were used to determine the relationship between MPOD and FM100 test scores. Kruskal-Wallis testing was used to investigate MPOD differences among different ethnicities and iris colors. Results: MPODs were normally distributed with a mean/SD = 0.38/0.13. Total error scores had a mean/SD of 10.7/9.7, but were not normally distributed. Iris reflectances had a mean/SD = 11.0/8.7. MPODs were not correlated to total error scores (p = 0.93). MPODs were also not correlated with iris reflectances (p = 0.28) even though MPODs differed significantly by iris color (brown = 0.44, hazel = 0.31, blue = 0.33, p = 0.04). Iris reflectances were not correlated with total error scores (p = 0.68). MPODs differed significantly (p = 0.003) between Asian and Caucasian subjects, 0.44 and 0.33, respectively. Conclusions: This study did not find a correlation between MPOD and hue discrimination as in some previous studies. While MPOD was associated with iris color and ethnicity as found in prior studies, it was not associated with iris reflectance, which may be a better indicator of ocular pigmentation compared to either iris color or ethnicity. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has revolutionized the teaching pedagogy in higher education as universities are forecasted to increase investments in learning technology infrastructure to transition away from traditional teaching methods. Therefore, it is crucial to investigate whether academics intend to continually integrate learning technologies as part of a permanent pedagogical change beyond the COVID-19 pandemic. Drawing upon the Unified Theory of Acceptance and Use of Technology (UTAUT), and Expectation Confirmation Model (ECM), this study examines the salient determinants influencing the continuance intention of academics to use learning technologies in their teaching pedagogy during and after COVID-19. Primary data collected from a private university was analyzed using the partial least squares structural equation modelling technique (PLS-SEM). The findings revealed two sequential mediating relationships which serve as the mechanism linking the relationship between facilitating conditions and their continuance intention to use learning technologies during and beyond the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

External body cooling by fan airflow mitigates the decrease in maximal oxygen uptake (V˙O2max) associated with cardiovascular (CV) drift during cycling in hot conditions. It remains unknown whether internal body cooling via ice slurry ingestion elicits a similar response. Purpose: This study aimed to test the hypothesis that ice slurry ingestion attenuates the magnitude of CV drift and accompanying decrement in V˙O2max during heat stress. Methods: Eight men completed a graded exercise test on a cycle ergometer in 22°C to measure V˙O2max. Then on three separate occasions (in randomly assigned counterbalanced treatment orders), they cycled at 60% V˙O2max in hot conditions (35°C, 40% RH) for 15 min, 45 min with tepid (23°C) fluid ingestion (45FL), or 45 min with ice (−1°C) slurry ingestion (45ICE), followed immediately by measurement of V˙O2max. The purpose of the separate 15- and 45-min trials was to measure CV drift and V˙O2max over the same time interval. Results: The increase in heart rate between 15 and 45 min was twice as large in 45FL (8.6%) compared with 45ICE (4.6%; P = 0.02). Stroke volume declined by 6.2% in 45FL but was maintained with 45ICE (P = 0.02). V˙O2peak decreased from 15 to 45 min by 8.6% and 9.0% in 45FL and 45ICE, respectively, but was not different between conditions (P = 0.79). Conclusion: Although ice slurry ingestion attenuated CV drift more than fluid ingestion, it did not mitigate the decline in V˙O2max. Contrary to previous findings, when ice slurry is ingested, changes in heart rate may not reflect changes in relative metabolic intensity during prolonged exercise in the heat. [ABSTRACT FROM AUTHOR]

Most legumes can form a unique type of lateral organ on their roots: root nodules. These structures host symbiotic nitrogen-fixing bacteria called rhizobia. Several different types of nodules can be found in nature, but the two beststudied types are called indeterminate and determinate nodules. These two types differ with respect to the presence or absence of a persistent nodule meristem, which consistently correlates with the cortical cell layers giving rise to the nodule primordia. Similar to other plant developmental processes, auxin signalling overlaps with the site of organ initiation and meristem activity. Here, we review how auxin contributes to early nodule development. We focus on changes in auxin transport, signalling, and metabolism during nodule initiation, describing both experimental evidence and computer modelling. We discuss how indeterminate and determinate nodules may differ in their mechanisms for generating localized auxin response maxima and highlight outstanding questions for future research. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to compare the mean findings and the repeatability of the minus lens (ML) amplitude of accommodation (AA) at 33 cm and 40 cm.Materials and Methods: AA was measured from the dominant eye of 120 fully corrected subjects using the ML procedure when viewing the target at both 33 and 40 cm. Each measurement was repeated between 24 and 48 hours after the first trial.Results: Mean AA when tested at 33 cm and 40 cm was 10.20 diopter (D) (standard deviation [SD] =1.24) and 8.85 D (SD = 1.23), respectively (P < 0.001). The limits of agreement of the measured amplitude calculated with taking into account of the replicates at 33 and 40 cm were - 0.19 (95% confidence interval [CI]: -0.34 to -0.04) and 2.53 (95% CI: 2.38 to 2.68), respectively. The repeatability of testing at the two distances 33 and 40 cm was ± 1.24 and ± 0.99, respectively. In addition, the retest reliability of measured amplitude using the intraclass correlation coefficient was 0.87 (95% CI: 0.789-0.920) at 33 cm and 0.91 (95% CI: 0.872-0.945) at 40 cm.Conclusion: There is no agreement in the obtained amplitude at the two measurement distances. Testing the ML AA at 40 cm may be superior given that a lower repeatability coefficient was observed. However, it is unclear whether the larger amplitude measured at 33 cm reflects a larger increase in accommodation (greater proximity effect) or a decrease in the ability to perceive the first slight sustained blur. [ABSTRACT FROM AUTHOR]

Initiation of symbiotic nodules in legumes requires cytokinin signaling, but its mechanism of action is largely unknown. Here, we tested whether the failure to initiate nodules in the Medicago truncatula cytokinin perception mutant cre1 (cytokinin response1) is due to its altered ability to regulate auxin transport, auxin accumulation, and induction of flavonoids. We found that in the cre1 mutant, symbiotic rhizobia cannot locally alter acro- and basipetal auxin transport during nodule initiation and that these mutants show reduced auxin (indole-3-acetic acid) accumulation and auxin responses compared with the wild type. Quantification of flavonoids, which can act as endogenous auxin transport inhibitors, showed a deficiency in the induction of free naringenin, isoliquiritigenin, quercetin, and hesperetin in cre1 roots compared with wild-type roots 24 h after inoculation with rhizobia. Coinoculation of roots with rhizobia and the flavonoids naringenin, isoliquiritigenin, and kaempferol, or with the synthetic auxin transport inhibitor 2,3,5,-triiodobenzoic acid, rescued nodulation efficiency in cre1 mutants and allowed auxin transport control in response to rhizobia. Our results suggest that CRE1-dependent cytokinin signaling leads to nodule initiation through the regulation of flavonoid accumulation required for local alteration of polar auxin transport and subsequent auxin accumulation in cortical cells during the early stages of nodulation. [ABSTRACT FROM AUTHOR]

Dofetilide Effect on f Waves in AF Introduction The electrocardiogram (ECG) fibrillatory (f) wave characteristics in atrial fibrillation (AF) could provide important information regarding the efficacy of antiarrhythmic drug therapy. Methods and Results To measure the effects of dofetilide on the surface ECG f wave characteristics in patients with persistent AF, baseline and post-drug (2 hours after first dose and after multiple doses) ECGs in 31 patients with persistent AF admitted for dofetilide loading were evaluated. A QRST template subtraction algorithm was used to yield an atrial ECG. Fast Fourier transform analysis was performed to evaluate the maximum organizational index (OI), the dominant frequency (DF) in the lead with max OI, the median DF for all leads, and the vector magnitude f wave amplitude. Dofetilide reduced DF in the lead with the max OI (6.32 ± 0.98 Hz at baseline vs. 4.83 ± 0.63 Hz after final dose, P < 0.0001) and median DF (6.46 ± 0.87 Hz vs. 4.92 ± 0.62 Hz, P < 0.0001). Dofetilide also increased the maximum OI from 0.52 ± 0.11 at baseline to 0.59 ± 0.11 after final dose (P = 0.02). Of the 29 patients with long-term follow-up, the 22 (76%) with recurrent AF on dofetilide had a lower baseline DF in the lead with the max OI (6.01 ± 1.08 vs. 6.89 ± 0.46; P = 0.05). The change in DF after dofetilide did not correlate with the change in QTc interval. Conclusions The standard ECG can be used to assess atrial rate in AF. This may be useful to assess antiarrhythmic drug effects for treatment of AF. [ABSTRACT FROM AUTHOR]

The article discusses internet censorship in China in relation to efforts to export Chinese social networking websites and internet filtering policies abroad. Chinese web resources noted including the search engine Baidu, the social media site Sina Weibo, and the video service Youku. The article "Chinese Communist Party-Backed Tech Giants Bring Censorship to the Global Stage" by Fei Chang Dao, retracted by the website TechCrunch after publication, is noted.

Atrial fibrillation (AF) electrograms are characterized by varying morphologies, amplitudes, and cycle lengths (CLs), presenting a challenge for automated detection of individual activations and the activation rate. In this study, we evaluate an algorithm to detect activations and measure CLs from AF electrograms. This algorithm iteratively adjusts the detection threshold level until the mean CL converges with the median CL to detect all individual activations. A total of 291 AF electrogram recordings from 13 patients (11 male, 58 ± 10 years old) undergoing AF ablation were obtained. Using manual markings by two independent reviewers as the standard, we compared the cycle length iteration algorithm with a fixed threshold algorithm and dominant frequency (DF) for the estimation of CL. At segment lengths of 10 s, when comparing the algorithm detected to the manually detected activation, the undersensing, oversensing, and total discrepancy rates were 2.4%, 4.6%, and 7.0%, respectively, and with absolute differences in mean and median CLs were 7.9 ± 9.6 ms and 5.6 ± 6.8 ms, respectively. These results outperformed DF and fixed threshold-based measurements. This robust method can be used for CL measurements in either real-time and offline settings and may be useful in the mapping of AF. [ABSTRACT FROM PUBLISHER]

Excess amounts of abdominal subcutaneous (SAT) and visceral (VAT) adipose tissue (AT) are associated with insulin resistance, even in normal-weight subjects. In contrast, gluteal-femoral AT (GFAT) is hypothesized to offer protection against insulin resistance. Dynamic PET imaging studies were undertaken to examine the contributions of both metabolic activity and size (volume) of these depots in systemic glucose metabolism. Nonobese, healthy volunteers (n = 15) underwent dynamic PET imaging uptake of [18F]FDG at a steady-state (20 mU·m-2·min-1) insulin infusion. PET images of tissue [18F]FDG activity were coregistered with MRI to derive K values for insulin-stimulated rates of fractional glucose uptake within tissue. Adipose tissue volume was calculated from DEXA and MRI. VAT had significantly higher rates of fractional glucose uptake per volume than SAT (P < 0.05) or GFAT (P < 0.01). KGFAT correlated positively (r = 0.67, P < 0.01) with systemic insulin sensitivity [glucose disappearance rate (Rd)] and negatively with insulin-suppressed FFA (r= -0.71, P < 0.01). SAT (r = -0.70, P < 0.01) and VAT mass (r = -0.55, P < 0.05) correlated negatively with Rd, but GFAT mass did not. We conclude that rates of fractional glucose uptake within GFAT and VAT are significantly and positively associated with systemic insulin sensitivity in nonobese subjects. Furthermore, whereas SAT and VAT amounts are confirmed to relate to systemic insulin resistance, GFAT amount is not associated with insulin resistance. These dynamic PET imaging studies indicate that both quantity and quality of specific AT depots have distinct roles in systemic insulin resistance and may help explain the metabolically obese but normal-weight phenotype. [ABSTRACT FROM AUTHOR]

Baroreflex Response and AF Dominant Frequency. Introduction: Parasympathetic stimulation is known to promote atrial fibrillation (AF) through shortening of atrial refractory periods. We hypothesized that baroreflex-mediated parasympathetic stimulation via phenylephrine (PE) infusion would increase AF rate as measured by dominant frequency (DF). Methods and Results: The protocol was performed in 27 patients (24 M, 59 ± 1 years old) prior to AF ablation. For 10 patients in AF, PE was infused until systolic blood pressure increased ≥30 mmHg. Electrograms were recorded in the left atrium before and after PE. DFs of each recording were calculated offline. Atrial effective refractory periods (ERPs) were measured before and after PE in 11 patients who were in sinus rhythm during the procedure. DFs were also measured in 6 patients in AF before and after complete parasympathetic blockade with atropine (0.04 mg/kg). PE resulted in increased RR intervals during sinus rhythm (1,170 ± 77 to 1,282 ± 85 ms, P = 0.03) and AF (743 ± 32 to 826 ± 30 ms, P = 0.03), consistent with parasympathetic effect on the sinus and AV nodes, respectively. DFs were decreased by PE in the left atrium (6.2 ± 0.2 to 6.0 ± 0.2 Hz, P = 0.004). Correspondingly, atrial ERPs significantly increased from 218 ± 13 to 232 ± 11 ms (P = 0.04). Atropine resulted in a decreasing trend in DF in the left atrium (5.9 ± 0.1 to 5.8 ± 0.1 Hz, P = 0.07). Conclusions: Despite baroreflex-mediated parasympathetic effect, PE produced a slowing of AF along with lengthening of ERP, while parasympathetic blockade also slowed DF. It is therefore likely that the direct and indirect adrenergic effects of PE on atrial electrophysiology are more prominent than its parasympathetic effects. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1045-1050, October 2012) [ABSTRACT FROM AUTHOR]

Objectives: This study sought to test the hypothesis that “virtual” electrophysiological studies (EPS) on an anatomic platform generated by 3-dimensional magnetic resonance imaging reconstruction of the left ventricle can reproduce the reentrant circuits of induced ventricular tachycardia (VT) in a porcine model of myocardial infarction. Background: Delayed-enhancement magnetic resonance imaging has been used to characterize myocardial infarction and “gray zones,” which are thought to reflect heterogeneous regions of viable and nonviable myocytes. Methods: Myocardial infarction by coronary artery occlusion was induced in 8 pigs. After a recovery period, 3-dimensional cardiac magnetic resonance images were obtained from each pig in vivo. Normal areas, gray zones, and infarct cores were classified based on voxel intensity. In the computer model, gray zones were assigned slower conduction and longer action potential durations than those for normal myocardium. Virtual EPS was performed and compared with results of actual in vivo programmed stimulation and noncontact mapping. Results: The left ventricular volumes ranged from 97.8 to 166.2 cm3, with 4.9% to 17.5% of voxels classified as infarct zones. Six of the 7 pigs in which VT developed during actual EPS were also inducible with virtual EPS. Four of the 6 pigs that had simulated VT had reentrant circuits that approximated the circuits seen with noncontact mapping, whereas the remaining 2 had similar circuits but propagating in opposite directions. Conclusions: This initial study demonstrates the feasibility of applying a mathematical model to magnetic resonance imaging reconstructions of the left ventricle to predict VT circuits. Virtual EPS may be helpful to plan catheter ablation strategies or to identify patients who are at risk of future episodes of VT. [ABSTRACT FROM AUTHOR]

AF Electrogram Complexity. Introduction: Complex fractionated atrial electrograms (CFAE) have been identified as targets for atrial fibrillation (AF) ablation. Robust automatic algorithms to objectively classify these signals would be useful. The aim of this study was to evaluate Shannon's entropy (ShEn) and the Kolmogorov-Smirnov (K-S) test as a measure of signal complexity and to compare these measures with fractional intervals (FI) in distinguishing CFAE from non-CFAE signals. Methods and Results: Electrogram recordings of 5 seconds obtained from multiple atrial sites in 13 patients (11 M, 58 ± 10 years old) undergoing AF ablation were visually examined by 4 independent reviewers. Electrograms were classified as CFAE if they met Nademanee criteria. Agreement of 3 or more reviewers was considered consensus and the resulting classification was used as the gold standard. A total of 297 recordings were examined. Of these, 107 were consensus CFAE, 111 were non-CFAE, and 79 were equivocal or noninterpretable. FIs less than 120 ms identified CFAEs with sensitivity of 87% and specificity of 79%. ShEn, with optimal parameters using receiver-operator characteristic curves, resulted in a sensitivity of 87% and specificity of 81% in identifying CFAE. The K-S test resulted in an optimal sensitivity of 100% and specificity of 95% in classifying uninterpretable electrogram from all other electrograms. Conclusions: ShEn showed comparable results to FI in distinguishing CFAE from non-CFAE without requiring user input for threshold levels. Thus, measuring electrogram complexity using ShEn may have utility in objectively and automatically identifying CFAE sites for AF ablation. (J Cardiovasc Electrophysiol, Vol. 21, pp. 649-655, June 2010) [ABSTRACT FROM AUTHOR]

Although frequency-domain analysis of heart rate variability (HRV) has been performed in the setting of exercise and recovery from exercise, the relationship of specific frequency components to sympathetic and parasympathetic inputs has not been validated in this setting. The aim of this study is to evaluate the relationship of frequency components of HRV to sympathetic and parasympathetic modulation in the setting of recovery after exercise using selective autonomic blockade. Normal subjects (n = 27, 17 men, 53 ± 7 yr old) underwent bicycle stress testing on four separate days. On day 1, a baseline study without autonomic blockade was performed. On days 2 through 4, either β-adrenergic, parasympathetic, or double blockade was administered during exercise and completed 3 mm before recovery. Continuous ECG was recorded for 5 mm starting from the end of exercise. Timeand frequency-domain measures of HRV were computed for each of the five I -mm segments of RR intervals. Parasympathetic blockade significantly decreased all the HRV measures compared with baseline (P < 0.02 for all). Root mean square of successive differences of RR intervals (rMSSD) was increased by β-adrenergic blockade (P < 0.0002). All the HRV measures except rMSSD showed increases with time after the first minute of recovery. The low frequency-to-high frequency ratio did not respond to autonomic blockade or to recovery time, consistent with the expected changes in sympathovagal influence. Root mean square (detrended SD) and rMSSD were highly correlated with the square root of the total power (r = 0.96) and high-frequency power (r = 0.95), respectively. Although there are marked reductions in the frequency-domain measures in recovery versus rest, the fluctuations in the lowand highfrequency bands respond to autonomic blockade in the expected fashion. Time-domain measures of HRV were highly correlated with frequency-domain measures and therefore provide a computationally more efficient assessment of autonomic influences during recovery from exercise that is less susceptible to anomalies of frequency domain analysis. [ABSTRACT FROM AUTHOR]

Introduction: Dominant frequency (DF) analysis of atrial electrograms has been used to characterize atrial fibrillation (AF). The aim of this study was to explore technical issues that may affect the estimation of local activation rate during AF using DF analysis. Methods and Results: Epicardial atrial electrograms recorded during AF from 10 dogs were used to evaluate the effects of unipolar versus bipolar recordings, bipolar electrode spacing, postrecording processing, far field ventricular depolarizations, ventricular template subtraction, and signal duration on DF analysis. Simulated electrograms were used to evaluate the effect of far field ventricular depolarizations and signal-to-noise ratio. DFs were compared with activation rates obtained by manual marking and the reproducibility of the DFs was evaluated. Bipolar electrograms were found to be preferable to unipolar electrograms. Preprocessing was a necessary step for bipolar signals, but also aided analysis of unipolar recordings. Ventricular far field depolarizations significantly affected DFs. Ventricular template subtraction helped DF analysis in signals with both minimal and significant ventricular components. A recording duration above 2 seconds was required for reliable DF measurements. Signal-to-noise ratios below 13 dB could also affect DF, particularly for signals with significant amplitude and frequency variation. Conclusions: Various factors affect DF analysis. Proper interpretation of DF analysis requires careful evaluation of the AF signals and robust processing techniques. [ABSTRACT FROM AUTHOR]

Dominant frequency analysis of atrial electrograms has been used to understand the pathophysiology of atrial fibrillation (AF). Although dominant frequency is an effective tool to estimate activation rate during AF, other factors besides activation rate may alter the results. Therefore, an adequate conceptual understanding of frequency domain analysis is required to properly use this technique and interpret the results. This review, while avoiding the use of formulas and equations, aims to explain fundamental theory of how signals can be decomposed into sine waves and how these sine waves relate to the activation rate detected from the electrograms. Through a series of examples and illustrations this relationship can be easily conceptualized. This will in turn allow the strengths and limitations of dominant frequency analysis to be better understood and improve its applicability to potential clinical usages. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to investigate the electrophysiologic profile of the pulmonary veins (PVs) and left atrium (LA) in response to autonomic manipulation. Background: The parasympathetic innervation of the PVs and posterior left atrium (PLA) is thought to contribute to focal atrial fibrillation (AF). We hypothesized that autonomic effects would be more prominent in these regions. Methods: In 14 dogs, epicardial mapping was performed in the PVs, PLA, and left atrial appendage (LAA) under the following conditions: baseline, 20-Hz cervical vagal stimulation (VS), propranolol (P), P + VS, and P + atropine. Effective refractory periods (ERPs) were measured, and conduction vectors were computed at multiple sites. Western blotting and immunostaining were performed for IKAch (Kir3.1/3.4). Results: The VS and P + VS caused more ERP shortening in the PV and PLA than in the LAA. The P + atropine caused greatest ERP prolongation in the LAA. Cumulative ERP change (ERP difference between P + VS and P + atropine) was greatest in the LAA and corresponded with expression of Kir3.1/3.4 (LAA > PLA ≥ PV). The ERP change in response to vagal manipulation was most heterogeneous in the PLA; this corresponded with a pronounced heterogeneity of Kir3.1 distribution in the PLA. With VS and/or P, there was evidence of regional conduction delay in the PVs with a significant change in activation direction. Similar activation changes were not seen in the PLA and LAA. Conclusions: The PVs and PLA demonstrate unique activation and repolarization characteristics in response to autonomic manipulation. The heterogeneity of vagal responses correlates with the pattern of IKAch distribution in the LA. The peculiar autonomic characteristics of the PVs and PLA might create substrate for re-entry and AF. [Copyright &y& Elsevier]

Ongoing support is critical to DSMES effectiveness, but difficult to realize, particularly in underserved areas with limited resources. The purpose of this study, initiated February 2020, was to evaluate the feasibility and acceptability of Telemedicine for Reach, Education, Access, Treatment, and Ongoing Support (TREAT-ON), a DSMES model delivered primarily through direct-to-home videoconferencing. Methods: High risk patients with diabetes (A1c >9% or unplanned care) from rural federally qualified health centers were referred to TREAT-ON. Participants completed an initial face-to-face or virtual visit with a Diabetes Care and Education Specialist (DCES) to assess needs and develop self-management treatment plan and behavioral goals. Planned follow-up visits, used to support achieving and sustaining goals and outcomes, were conducted through videoconferencing. To assess feasibility and acceptability over first 3-months of participation, visit frequency, duration, completion rates, and technology issues were tracked and patients completed the Telehealth Usability Questionnaire (TUQ). Results: Participants (n=25) were 60% female, 92% White, mean age 47.6±13.6y, mean A1c 11.5±1.8% and 76% had Medicare or Medicaid. They participated in 3 video visits, on average, lasting a mean of 35 minutes/visit. Of all scheduled video visits (n=99), 71% were successfully completed and 23% had technology issues (difficulty setting up system, connectivity issues). The TUQ revealed that participants were highly satisfied with the TREAT-ON videoconferencing approach (4.7/5), finding it useful (4.5/5), easy to learn/use (4.5/5), reliable (4.3/5), with quality interface (4.6/5) and interaction (4.7/5). Conclusion: This telehealth DSMES model offers a promising approach to improve opportunities for ongoing support to vulnerable individuals in underserved communities. Disclosure: J. S. Krall: Research Support; Self; Becton, Dickinson and Company, Sanofi. J. Ng: Research Support; Self; Sanofi-Aventis. P. A. Johnson: None. S. L. Reynolds: None. L. M. Siminerio: Advisory Panel; Self; Abbott Diabetes, Bayer U. S., Research Support; Self; Becton, Dickinson and Company. Funding: National Institute of Diabetes And Digestive and Kidney Diseases (R34DK123370) [ABSTRACT FROM AUTHOR]

Introduction: Multiple analysis techniques evaluate electrograms during atrial fibrillation (AF), but none have been established to guide catheter ablation. This study compares electrogram properties recorded from multiple right (RA) and left atrial (LA) sites. Methods: Multisite LA/RA mapping (281 ± 176/239 ± 166 sites/patient) was performed in 42 patients (30 males, age 63 ± 9 years) undergoing first (n = 32) or redo‐AF ablation (n = 10). All electrogram recordings were visually reviewed and artifactual signals were excluded leaving a total of 21 846 for analysis. Electrogram characteristics evaluated were cycle length (CL), amplitude, Shannon's entropy (ShEn), fractionation interval, dominant frequency, organizational index, and cycle length of most recurrent morphology (CLR) from morphology recurrence plot analysis. Results: Electrogram characteristics were correlated to each other. All pairwise comparisons were significant (p <.001) except for dominant frequency and CLR (p =.59), and amplitude and dominant frequency (p =.38). Only ShEn and fractionation interval demonstrated a strong negative correlation (r = −.94). All other pairwise comparisons were poor to moderately correlated. The relationships are highly conserved among patients, in the RA versus LA, and in those undergoing initial versus redo ablations. Antiarrhythmic drug therapy did not have a significant effect on electrogram characteristics, except minimum ShEn. Electrogram characteristics associated with ablation outcome were shorter minimum CLR, lower minimum ShEn, and longer mimimum CL. There was minimal overlap between the top 10 sites identified by one electrogram characteristic and the top 10 sites identified by the other 10 characteristics. Conclusion: Multiple techniques can be employed for electrogram analysis in AF. In this analysis of eight different electrogram characteristics, seven were poorly to moderately correlated and do not identify similar locations. Only some characteristics were predictive of ablation outcome. Further studies to consider electrogram properties, perhaps in combination, for categorizing and/or mapping AF are warranted. [ABSTRACT FROM AUTHOR]

Introduction: Greater cardiovascular (CV) drift occurs during cycling compared to running in temperate conditions. CV drift also corresponds to proportional reductions in maximal oxygen uptake (V˙O2max) during heat stress. Whether exercise mode differentially affects CV drift—and accompanying declines in V˙O2max—during heat stress is uncertain. The purpose of this study was to test the hypothesis that a greater magnitude of CV drift, accompanied by a greater decrement in V˙O2max, occurs during cycling compared to running in hot conditions. Methods: 7 active men (mean ± SD; age = 25 ± 6 yr, percent body fat = 11.9% ± 2.4%) completed a control graded exercise test (GXT) on a cycle ergometer and treadmill. Then on separate, counterbalanced occasions they completed 15 or 45 min of cycling or running at 60% V˙O2max in 35°C, immediately followed by a GXT to measure V˙O2max (4 trials total). The separate 15- and 45-min trials were designed to measure CV drift and V˙O2max over the same time interval. Results: Heart rate increased 19% and 17% and stroke volume decreased 20% and 15% between 15 and 45 min during running and cycling, respectively, but modes were not different (all P > 0.05). Despite a 1.8°C larger core-to-skin thermal gradient during running, decrements in V˙O2peak were not different between exercise modes (95% CI for difference in change scores between 15 and 45 min: −0.2, 0.3). Conclusions: CV strain (indexed as CV drift) during prolonged exercise in the heat corresponds to reduced V˙O2max, irrespective of exercise mode or the thermal gradient. As such, the upward drift in heart rate associated with CV drift reflects increased relative metabolic intensity (%V˙O2max) during prolonged cycling or running in the heat. [ABSTRACT FROM AUTHOR]

Heart failure (HF) with recovered ejection fraction (HFrecEF) is an increasingly recognized yet not well understood phenotype. Little is known about electrical parameters associated with myocardial recovery in acute systolic HF. We identified a subset of 87 patients from a non-ischemic cardiomyopathy cohort with left ventricular ejection fraction (LVEF) < 40% during index HF hospitalization. HFrecEF was defined as follow-up LVEF ≥40% and ≥ 10% improvement from baseline. We analyzed baseline and follow up electrocardiograms (ECG) in this group for several electrical parameters known to reflect repolarization heterogeneity. Among 87 patients, 30 (34%) patients recovered in a median of 122 (IQR: 58-275) days after index hospitalization. Baseline demographics were similar among HFrecEF versus persistent HFrEF except for increased diabetes in the persistent HFrEF cohort. Patients with HFrecEF had baseline decreased QRST angle, decreased QT dispersion, and less negative signed JT area compared to persistent HFrEF. Patients with HFrecEF had greater decrease in QT dispersion and QTc duration, and greater increase in the signed JT and TpTe areas over time. Baseline QRST angle correlated with longitudinal and circumferential strain and myocardial systolic performance (MSP). Signed JT area correlated with increased baseline LVEF, smaller baseline LV dimensions, increased longitudinal and circumferential strain, and MSP. Signed TpTe correlated with increased longitudinal and circumferential strain, and MSP. Several conventional and novel ECG parameters that reflect repolarization heterogeneity may differentiate patients with acute HF who ultimately recover LVEF. These parameters are associated with baseline structural parameters and are dynamic during recovery. • Heart failure with recovered ejection fraction is a newly recognized phenotype. • Increased repolarization heterogeneity on ECG is associated with adverse outcomes. • Repolarization is less heterogeneous on ECG in patients with HFrEF who recover. • Repolarization heterogeneity correlates with baseline structural parameters. • ECG parameters of repolarization are dynamic during the recovery process. [ABSTRACT FROM AUTHOR]

Background: Sporadic outbreaks of COVID-19 remain a threat to public healthcare, especially if vaccination levels do not improve. As Malaysia begins its transition into the endemic phase, it is essential to identify the key determinants of COVID-19 vaccination intention amongst the pockets of the population who are still hesitant. Therefore, focusing on a sample of individuals who did not register for the COVID-19 vaccination, the current study integrated two widely used frameworks in the public health domain—the health belief model (HBM) and the theory of reasoned action (TRA)—to examine the inter-relationships of the predictors of vaccination intention amongst these individuals. Methodology: Primary data from 117 respondents who did not register for the COVID-19 vaccination were collected using self-administered questionnaires to capture predictors of vaccination intention amongst individuals in a Malaysian context. The partial least squares structural equation modeling (PLS-SEM) technique was used to analyze the data. Results: Subjective norms and attitude play key mediating roles between the HBM factors and vaccination intention amongst the unregistered respondents. In particular, subjective norms mediate the relationship between cues to action and vaccination intention, highlighting the significance of important others to influence unregistered individuals who are already exposed to information from mass media and interpersonal discussions regarding vaccines. Trust, perceived susceptibility, and perceived benefits indirectly influence vaccination intention through attitude, indicating that one's attitude is vital in promoting behavioral change. Conclusion: This study showed that the behavioral factors could help understand the reasons for vaccine refusal or acceptance, and shape and improve health interventions, particularly among the vaccine-hesitant group in a developing country. Therefore, policymakers and key stakeholders can develop effective strategies or interventions to encourage vaccination amongst the unvaccinated for future health pandemics by targeting subjective norms and attitude. [ABSTRACT FROM AUTHOR]

Surface ECG f Wave Analysis X Introduction Dominant frequency (DF) analysis of electrocardiograms (ECGs) from patients with paroxysmal (PAF) and persistent (PeAF) atrial fibrillation has identified higher DFs in PeAF. We therefore hypothesized that among patients initially presenting to the emergency department (ED) with new onset AF, surface ECG features could differentiate PeAF from PAF. Methods and Results Initial 12-lead ECGs from patients presenting to the ED with a first episode of symptomatic AF were analyzed. Following QRS-T subtraction, fast Fourier transform (FFT) analysis of the AF fibrillatory waves was performed to measure DF and organization index (OI). Median DF of all leads and the DF in the lead with maximum OI were determined. Maximum f wave amplitude and vector magnitudes were measured. One hundred sixty-one patients (age 59 ± 16 years, 68% men) were included in this analysis, of whom 96 (58%) spontaneously converted to sinus rhythm within 7 days (PAF group). The remaining 65 patients underwent cardioversion or remained in AF (PeAF group). ECG features (DF, OI, f wave amplitude, and vector magnitude) did not differ among PAF and PeAF patients. Conclusions ECG features (DF, OI, amplitude, vector magnitude) do not differ among patients with PAF versus PeAF when the ECGs are obtained at the initial onset of symptoms. Thus, prior data showing higher DF in PeAF likely reflect electrophysiologic remodeling rather than a marker for any specific type of AF or extent of underlying substrate. [ABSTRACT FROM AUTHOR]

This study focuses on students from vulnerable communities who are at the bottom 40% of the population income distribution in a developing country. These students are more likely to face challenges in accessing quality education, with many having a high propensity to drop out of school. Computer-aided education is one way to increase academic enthusiasm and creativity amongst these students to enable them to complete their studies and acquire skills for an information-driven society. Drawing upon the Unified Theory of Acceptance and Use of Technology (UTAUT) model, this study examines the key factors influencing computer use for learning amongst students and if a computer-aided learning experience can lead to improved academic enthusiasm and creativity. Primary data collected from 414 primary school students from the targeted segment of the population was analysed using the partial least squares structural equation modelling technique (PLS-SEM). The findings revealed that performance expectancy, social influence, and facilitating conditions determined students' computer use for learning. Additionally, computer use for learning influenced the academic enthusiasm and creativity of students. The findings offer insights on the potential implications in the formulation of computer-based education initiatives for students from a vulnerable group in a developing country context. [ABSTRACT FROM AUTHOR]

The adoption of a holistic approach to root research, that is, one that takes into account all categories of root traits, from anatomy to root morphology, physiology and architecture, as well as interactions with the rhizosphere microbiota, was emphasised as a crucial step in facing the challenges posed by global change. Keywords: Ambassador Program; ISRR11; rhizosphere; root phenotyping; root traits; Rooting2021; roots EN Ambassador Program ISRR11 rhizosphere root phenotyping root traits Rooting2021 roots 2149 2154 6 08/22/22 20220915 NES 220915 Emerging frontiers: root and rhizosphere research in the context of global environmental chan... Natural ecosystems and agricultural production have been threatened by multifaceted global environmental changes. ISRR11, rhizosphere, root traits, Ambassador Program, root phenotyping, Rooting2021, roots Root biology never sleeps: 11th Symposium of the International Society of Root Research (ISRR11) and the 9th International Symposium on Root Development (Rooting2021), 24-28 May 2021. [Extracted from the article]