Non-invasive assessment of oocyte developmental competence

Published: 18 October 2022Oocyte quality is a key factor influencing IVF success. The oocyte and surrounding cumulus cells, known collectively as the cumulus oocyte complex (COC), communicate bi-directionally and regulate each other’s metabolic function to support oocyte growth and maturation. Many studies have attempted to associate metabolic markers with oocyte quality, including metabolites in follicular fluid or ‘spent medium’ following maturation, gene expression of cumulus cells and measuring oxygen consumption in medium surrounding COCs. However, these methods fail to provide spatial metabolic information on the separate oocyte and cumulus cell compartments. Optical imaging of the autofluorescent cofactors – reduced nicotinamide adenine dinucleotide (phosphate) [NAD(P)H] and flavin adenine dinucleotide (FAD) – has been put forward as an approach to generate spatially resolved measurements of metabolism within individual cells of the COC. The optical redox ratio (FAD/[NAD(P)H + FAD]), calculated from these cofactors, can act as an indicator of overall metabolic activity in the oocyte and cumulus cell compartments. Confocal microscopy, fluorescence lifetime imaging microscopy (FLIM) and hyperspectral microscopy may be used for this purpose. This review provides an overview of current optical imaging techniques that capture the inner biochemistry within cells of the COC and discusses the potential for such imaging to assess oocyte developmental competence.Tiffany C. Y. Tan and Kylie R. Dunnin

The G-O Rule and Waldmeier Effect in the Variations of the Numbers of Large and Small Sunspot Groups

We have analysed the combined Greenwich and Solar Optical Observing Network (SOON) sunspot group data during the period of 1874-2011 and determined variations in the annual numbers (counts) of the small, large and big sunspot groups (these classifications are made on the basis of the maximum areas of the sunspot groups). We found that the amplitude of an even-numbered cycle of the number of large groups is smaller than that of its immediately following odd-numbered cycle. This is consistent with the well known Gnevyshev and Ohl rule or G-O rule of solar cycles, generally described by using the Zurich sunspot number (Rz). During cycles 12-21 the G-O rule holds good for the variation in the number of small groups also, but it is violated by cycle pair (22, 23) as in the case of Rz. This behaviour of the variations in the small groups is largely responsible for the anomalous behaviour of Rz in cycle pair (22, 23). It is also found that the amplitude of an odd-numbered cycle of the number of small groups is larger than that of its immediately following even-numbered cycle. This can be called as `reverse G-O rule'. In the case of the number of the big groups, both cycle pairs (12, 13) and (22, 23) violated the G-O rule. In many cycles the positions of the peaks of the small, large, and big groups are different and considerably differ with respect to the corresponding positions of the Rz peaks. In the case of cycle 23, the corresponding cycles of the small and large groups are largely symmetric/less asymmetric (Waldmeier effect is weak/absent) with their maxima taking place two years later than that of Rz. The corresponding cycle of the big groups is more asymmetric (strong Waldmeier effect) with its maximum epoch taking place at the same time as that of Rz.Comment: 13 pages, 5 figures, 1 table, accepted by Solar Physic

Modulational instability of two pairs of counter-propagating waves and energy exchange in two-component media

The dynamics of two pairs of counter-propagating waves in two-component media is considered within the framework of two generally nonintegrable coupled Sine-Gordon equations. We consider the dynamics of weakly nonlinear wave packets, and using an asymptotic multiple-scales expansion we obtain a suite of evolution equations to describe energy exchange between the two components of the system. Depending on the wave packet length-scale vis-a-vis the wave amplitude scale, these evolution equations are either four non-dispersive and nonlinearly coupled envelope equations, or four non-locally coupled nonlinear Schroedinger equations. We also consider a set of fully coupled nonlinear Schroedinger equations, even though this system contains small dispersive terms which are strictly beyond the leading order of the asymptotic multiple-scales expansion method. Using both the theoretical predictions following from these asymptotic models and numerical simulations of the original unapproximated equations, we investigate the stability of plane-wave solutions, and show that they may be modulationally unstable. These instabilities can then lead to the formation of localized structures, and to a modification of the energy exchange between the components. When the system is close to being integrable, the time-evolution is distinguished by a remarkable almost periodic sequence of energy exchange scenarios, with spatial patterns alternating between approximately uniform wavetrains and localized structures.Comment: 35 pages, 13 figure

Integrated engineering environments for large complex products

An introduction is given to the Engineering Design Centre at the University of Newcastle upon Tyne, along with a brief explanation of the main focus towards large made-to-order products. Three key areas of research at the Centre, which have evolved as a result of collaboration with industrial partners from various sectors of industry, are identified as (1) decision support and optimisation, (2) design for lifecycle, and (3) design integration and co-ordination. A summary of the unique features of large made-to-order products is then presented, which includes the need for integration and co-ordination technologies. Thus, an overview of the existing integration and co-ordination technologies is presented followed by a brief explanation of research in these areas at the Engineering Design Centre. A more detailed description is then presented regarding the co-ordination aspect of research being conducted at the Engineering Design Centre, in collaboration with the CAD Centre at the University of Strathclyde. Concurrent Engineering is acknowledged as a strategy for improving the design process, however design coordination is viewed as a principal requirement for its successful implementation. That is, design co-ordination is proposed as being the key to a mechanism that is able to maximise and realise any potential opportunity of concurrency. Thus, an agentoriented approach to co-ordination is presented, which incorporates various types of agents responsible for managing their respective activities. The co-ordinated approach, which is implemented within the Design Co-ordination System, includes features such as resource management and monitoring, dynamic scheduling, activity direction, task enactment, and information management. An application of the Design Co-ordination System, in conjunction with a robust concept exploration tool, shows that the computational design analysis involved in evaluating many design concepts can be performed more efficiently through a co-ordinated approach

The phase relation between sunspot numbers and soft X-ray flares

To better understand long-term flare activity, we present a statistical study on soft X-ray flares from May 1976 to May 2008. It is found that the smoothed monthly peak fluxes of C-class, M-class, and X-class flares have a very noticeable time lag of 13, 8, and 8 months in cycle 21 respectively with respect to the smoothed monthly sunspot numbers. There is no time lag between the sunspot numbers and M-class flares in cycle 22. However, there is a one-month time lag for C-class flares and a one-month time lead for X-class flares with regard to sunspot numbers in cycle 22. For cycle 23, the smoothed monthly peak fluxes of C-class, M-class, and X-class flares have a very noticeable time lag of one month, 5 months, and 21 months respectively with respect to sunspot numbers. If we take the three types of flares together, the smoothed monthly peak fluxes of soft X-ray flares have a time lag of 9 months in cycle 21, no time lag in cycle 22 and a characteristic time lag of 5 months in cycle 23 with respect to the smoothed monthly sunspot numbers. Furthermore, the correlation coefficients of the smoothed monthly peak fluxes of M-class and X-class flares and the smoothed monthly sunspot numbers are higher in cycle 22 than those in cycles 21 and 23. The correlation coefficients between the three kinds of soft X-ray flares in cycle 22 are higher than those in cycles 21 and 23. These findings may be instructive in predicting C-class, M-class, and X-class flares regarding sunspot numbers in the next cycle and the physical processes of energy storage and dissipation in the corona.Comment: 8 pages, 3 figures, Accepted for publication in Astrophysics & Space Scienc

Associations of Leisure-Time Physical Activity and Television Viewing With Life Expectancy Free of Nonfatal Cardiovascular Disease: The ARIC Study

Background High levels of physical activity have been associated with longer life expectancy free of cardiovascular disease (CVD), but specific types of CVD and sedentary behavior have not been examined. We examined associations of leisure-time moderate-to-vigorous physical activity (LTPA) and television viewing with life expectancy free of 3 types of CVD. Methods and Results We included 13 534 participants from the ARIC (Atherosclerosis Risk in Communities) cohort. We used multistate survival models to estimate associations of LTPA in the past year (no LTPA, less than the median, equal to or greater than the median) and television viewing (often or very often, sometimes, seldom or rarely) with life expectancy at age 50 free of nonfatal coronary heart disease (CHD), stroke, and heart failure (HF). Over 27 years of follow-up, 4519 participants developed one of the 3 nonfatal CVDs and 5475 deaths occurred. Compared with participants who engaged in no LTPA, participants who engaged in LTPA equal to or greater than the median had longer life expectancy free of nonfatal CHD (men: 1.5 years [95% CI, 1.0-2.0]; women: 1.6 years [95% CI, 1.1-2.2]), stroke (men: 1.8 years [95% CI, 1.2-2.3]; women: 1.8 years [95% CI, 1.3-2.3]), and HF (men: 1.6 years [95% CI, 1.1-2.1]; women: 1.7 years [95% CI, 1.2-2.2]). Compared with viewing more television, watching less television was associated with longer life expectancy free of CHD, stroke, and HF (≈0.8 year). Conclusions Higher levels of LTPA and less television viewing were associated with longer life expectancy free of CHD, stroke, and HF. Engaging in LTPA and watching less television may increase the number of years lived free of CHD, stroke, and HF

Associations of leisure-time physical activity and television viewing with life expectancy cancer-free at age 50: The ARIC study

Background: Physical activity has been associated with longer chronic disease-free life expectancy, but specific cancer types have not been investigated. We examined whether leisure-time moderate- to-vigorous physical activity (LTPA) and television (TV) viewing were associated with life expectancy cancer-free. Methods: We included 14,508 participants without a cancer history from the Atherosclerosis Risk in Communities (ARIC) study. We used multistate survival models to separately examine associations of LTPA (no LTPA, <median, ≥median) and TV viewing (seldom/never, sometimes, often/very often) with life expectancy cancer-free at age 50 from invasive colorectal, lung, prostate, and postmenopausal breast cancer. Models were adjusted for age, gender, race, ARIC center, education, smoking, and alcohol intake. Results: Compared with no LTPA, participants who engaged in LTPA ≥median had a greater life expectancy cancer-free from colorectal [men-2.2 years (95% confidence interval (CI), 1.7-2.7), women-2.3 years (95% CI, 1.7-2.8)], lung [men-2.1 years (95% CI, 1.5-2.6), women-2.1 years (95% CI, 1.6-2.7)], prostate [1.5 years (95% CI, 0.8-2.2)], and postmenopausal breast cancer [2.4 years (95% CI, 1.4-3.3)]. Compared with watching TV often/very often, participants who seldom/never watched TV had a greater colorectal, lung, and postmenopausal breast cancer-free life expectancy of ∼1 year. Conclusions: Participating in LTPA was associated with longer life expectancy cancer-free from colorectal, lung, prostate, and postmenopausal breast cancer. Viewing less TV was associated with more years lived cancer-free from colorectal, lung, and postmenopausal breast cancer. Impact: Increasing physical activity and reducing TV viewing may extend the number of years lived cancer-free

Antimicrobial resistance profile of Salmonella present in organic farming in Selangor, Malaysia

Presence of Salmonella in organic farming may lead to contamination in fresh produce. This study was designed to detect Salmonella contamination in organic vegetable farm situated in Serdang and to evaluate the antibiotic susceptibility profiles of the isolates. A total of 460 samples of brinjal, cucumber, ladies’ fingers and soil were collected and examined for the presence of Salmonella. The obtained isolates were identified and confirmed by biochemical characterization and serotyping. Antibiotic sensitivity profiles of the isolates were determined by using agar disk diffusion method. Salmonella spp. was detected in brinjal (1.7%, n=2), cucumber (1.7%, n=2), ladies’ fingers (2.5%, n=3) and soil (5.0%, n=5) samples. The prevalent serovars were Salmonella enterica ser. Senftenberg, S. enterica ser. Weltevreden and S. enterica ser. Corvallis. All strains were resistance to penicillin and vancomycin, with multiple antibiotic resistance (MAR) index between 0.21 and 0.36, demonstrated here as multi-drug resistant (MDR) Salmonella. The result highlighted that organic vegetables constituted potential sources of Salmonella, informing continuous monitoring and tightened surveillance are necessary to ensure food safety

Comparison of Medicare Claims-based Proxy Measures of Poor Function and Associations With Treatment Receipt and Mortality in Older Colon Cancer Patients

Background: Multiple claims-based proxy measures of poor function have been developed to address confounding in observational studies of drug effects in older adults. We evaluated agreement between these measures and their associations with treatment receipt and mortality in a cohort of older colon cancer patients. Methods: Medicare beneficiaries age 66+ diagnosed with stage II-III colon cancer were identified in the Surveillance, Epidemiology, and End Results-Medicare database (2004-2011). Poor function was operationalized by: (1) summing the total poor function indicators for each model; and (2) estimating predicted probabilities of poor function at diagnosis. Agreement was evaluated using Fleiss' κ and Spearman's correlation. Associations between proxy measures and: (1) laparoscopic versus open surgery; (2) chemotherapy versus none; (3) 5-fluorouracil (5FU)+oxaliplatin (FOLFOX) versus 5FU monotherapy; and (4) 1-year mortality were estimated using log-binomial regression, controlling for age, sex, stage, and comorbidity. Survival estimates were stratified by functional group, age, and comorbidity. Results: Among 29,687 eligible colon cancer patients, 67% were 75+ years and 45% had stage III disease. Concordance across the poor function indicator counts was moderate (κ: 0.64) and correlation of predicted probability measures varied (ρ: 0.21-0.74). Worse function was associated with lower chemotherapy and FOLFOX receipt, and higher 1-year mortality. Within age and comorbidity strata, poor function remained associated with mortality. Conclusions: While agreement varied across the claims-based proxy measures, each demonstrated anticipated associations with treatment receipt and mortality independent of comorbidity. Claims-based comparative effectiveness studies in older populations should consider applying one of these models to improve confounding control