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There is limited understanding of the relationship between the growth of spoilage microflora and fresh meat color. Therefore, the objective of this study was to investigate the impact of the growth of common spoilage bacteria on the color stability of color-stable (longissimus lumborum; LL) and color-labile (psoas major; PM) beef muscles. Beef striploins (LL) and tenderloins (PM) (USDA Choice, n = 8) were wet aged (14 d), after which they were decontami- nated and fabricated into 1.27-cm thick steaks. Steaks were randomly assigned as decontaminated (DCON) or inoculated (INOC). The surface of INOC steaks was inoculated (ca. 4 log CFU/cm 2 ) with a mixture of spoilage bacteria, while an equivalent volume of phosphate-buffered saline was applied to the surface of DCON steaks. Steaks were aerobically retail displayed for up to 9 d. Each day, objective and subjective color evaluation and microbiological analyses were conducted. Aerobic plate counts on INOC steaks were 8.9 (LL) and 9.3 (PM) log CFU/cm 2 at the end of retail display. Corresponding counts on DCON steaks were < 2.7 (LL) and < 3.4 (PM) log CFU/cm2. For LL steaks, there was a treatment × display day interaction (P < 0.05) for lightness (L* ), redness (a*), yellowness (b*), lean color scores, surface discoloration, and bac- terial levels. On days 6 – 8, redness was lower (P < 0.05) for INOC compared to DCON LL steaks, while lean color scores and surface discoloration were lower (P < 0.05) for DCON compared to INOC LL steaks. For PM, there was a treatment × display day interaction (P < 0.05) for a* values, surface discoloration, and bacterial levels. Surface discoloration was greater (P < 0.05) for INOC steaks compared with DCON steaks on days 4 and 5. The results indicate a connection between surface discoloration and microbial growth on beef LL and PM steaks, and differences in bacterial growth kinetics could explain some of the differential color stabilities between these muscles.

Background/Objectives: Early postmortem mitochondrial function and apoptotic activation affect meat quality development. Nicotinamide riboside (NR) supplementation to pigs prior to harvest can improve pork color stability, but its mechanism remains unclear. This study aimed to evaluate the impact of NR supplementation on early postmortem mitochondrial functionality and apoptosis. Methods: Sixteen pigs (N = 16) were individually fed a control or NR-supplemented diet (30 mg·kg body weight−1·d−1) for 10 days prior to harvest. Longissimus dorsi muscle samples were collected at 45 min and 24 h postmortem and analyzed for mitochondrial functionality using high-resolution respirometry and apoptotic protein abundance (apoptosis regulator Bcl-2-associated X (BAX), apoptotic inducing factor (AIF), and caspase 3 (CASP3)) via immunoblotting. Results: NR-supplemented muscle exhibited lower proton leak-associated respiration at 45 min postmortem (p < 0.05), followed by a slower accumulation of mitochondrial outer membrane permeabilization (MOMP; p < 0.05) and a slower loss of mitochondrial integral function (p < 0.05) from 45 min to 24 h postmortem. NR supplementation decreased BAX abundance at 45 min postmortem but increased mature AIF abundance (62 kDa) at 24 h postmortem (p < 0.05). The abundance of CASP3 fragments (~29 kDa) decreased from 45 min to 24 h postmortem, independent of treatment (p < 0.05). Conclusions: NR supplementation demonstrated the potential to protect mitochondrial integral function and alleviate apoptotic activation in early postmortem porcine skeletal muscle, which might contribute to a higher meat color stability in NR-supplemented pork during retail display.

The prevalence of highly marbled cattle breeds, such as Wagyu, has increased in the US due to consumer demand for higher-quality beef. The ability to grade highly marbled carcasses accurately and consistently, particularly with quantifying intramuscular fat content for validation, remains a challenging task for the Wagyu beef industry. New camera grading technologies have been proposed by VIAS VBG 2000 (e+v Technology GmbH & Co. KG, 2021), Meat Image Japan (MIJ), and MasterBeef (MB) for Wagyu-influenced beef carcass assessment based on advanced image analysis. However, the intramuscular fat measurements of these camera technologies and the actual percent intramuscular fat (%IMF) in the longissimus at the 12/13th rib have yet to be investigated. Chilled carcasses (n = 173) from F1 Wagyu cattle were ribbed between the 12th and 13th ribs, and the left carcass sides were imaged with the E+V, MIJ, and MB cameras. Additionally, the marbling score was assigned by a team of 3 US Department of Agriculture (USDA) graders. Samples from the longissimus thoracis were collected, and the %IMF of the muscle was determined in triplicate. Linear regressions and descriptive statistics were done using JMP (Statistical Discovery, NC, USA) software. Camera fat-related measurements were linearly correlated, and R2 was calculated. The E+V camera had the highest %IMF predictability of all cameras (P < 0.0001) using the marbling score (R2 = 0.6450) estimate. The MIJ camera presented prediction accuracy between the other 2 technologies (P < 0.0001) of %IMF with identical R2 for fat percent and fat score estimates (R2 = 0.5952). The MB camera had the lowest predictability (P < 0.0001) of %IMF using the measured marbling score (R2 = 0.3269), marbling area (R2 = 0.3333), and marbling percent (R2 = 0.3269) estimates from the instrument. As technology advances, new technologies will provide alternative means for grading Wagyu-influenced carcasses. Additionally, these findings could aid the implementation of the USDA pilot program for remote carcass grading.

The storage of meat at temperatures below regular chilling can extend the storage shelf-life of fresh beef. However, the retail shelf-life of beef after extended storage has not been thoroughly investigated. This study evaluated the retail shelf-life of steaks derived from 10 upper two-thirds Choice beef inside rounds, bone-in ribeyes, and striploins that had been stored at low temperature (LT; −2.7 ± 0.3°C) for different periods of time. The subprimals were fabricated into 3 pieces, vacuum packaged, and randomly allocated to an LT storage time of 60, 75, and 90 d. After each storage time, subprimal portions were fabricated into steaks, overwrapped, and placed in a retail display case (3°C) for 7 d. Steaks were evaluated daily for instrumental and visual color and microbial levels (aerobic plate counts [APC], lactic acid bacteria counts, and Pseudomonas spp. counts) on days 0, 2, 4, and 7. For all subprimals, the initial redness (a* values) of LT75 and LT90 steaks was greater (P < 0.05) than that of LT60 steaks. In general, irrespective of LT storage time or retail display day, visual panelists did not detect differences in lean color and discoloration of steaks. For all subprimals, the APC of LT60 steaks on days 0, 2, and 4 of the retail display were lower (P < 0.05) than those of LT75 and LT90 samples. Samples from LT60 presented a longer microbial retail shelf-life than those from LT75 and LT90 due to lower initial microbial loads following LT storage. However, the retail shelf-life of samples from LT75 and LT90 was similar. Overall, these results demonstrated the impact of LT60, LT75, and LT90 on the retail shelf-life of different beef subprimals.

Abstract The quantity and accuracy of satellite-geodetic measurements have increased over time, revolutionizing the monitoring of tectonic processes. Global Navigation Satellite System (GNSS) and satellite radar signals provide observations beyond ground deformation, including how earthquake and tsunami processes affect variations in the ionosphere. Here, we study the Hunga Tonga Hunga Ha’apai (HTHH) volcanic eruption 2022 and its associated tsunami propagation with the analysis GNSS derived Total Electron Content (TEC), Synthetic Aperture Radar (SAR) Sentinel-1 data, complemented with tide gauge observations. We utilize GNSS sites data within a ~ 5000 km radius from the volcanic eruption for estimating the ionospheric perturbation as Vertical TEC. We give evidence on the detection of acoustic gravity, internal gravity, and atmospheric Lamb waves signatures in the TEC perturbation. In particular, the internal gravity waves that concentrated in the southwest of Tonga, directly correlates with the observed tsunami propagation direction as accounted by the tide gauge measurements. However, the acoustic gravity wave signature in the TEC is dominant in the north direction suggesting a surface deformation, which could be verified using Sentinel-1A SAR amplitude data. The analysis presented herein shows that within 5 h of the volcanic eruption, the central part of the HTHH island landscape disappeared with the biggest explosion. The unprecedented detail resolved by integrating satellite data yields previously unknown details of the deformation of the 2022 HTHH volcano eruption.

Abstract Background Liver abscesses (LAs) are one of the most common and important problems faced by the beef industry. The most efficacious method for the prevention of LAs in North America is through dietary inclusion of low doses of antimicrobial drugs such as tylosin, but the mechanisms by which this treatment prevents LAs are not fully understood. LAs are believed to result from mucosal barrier dysfunction in the gastrointestinal tract (GIT) allowing bacterial translocation to the liver via the portal vein, yet differences in the GIT microbiome of cattle with and without LAs have not been explored. Here, we characterized microbial communities from LAs, rumen, ileum, and colon from the same cattle for the first time. Results Results demonstrate that tylosin supplementation was associated with differences in microbial community structure in the rumen and small intestine, largely because of differences in the predominance of Clostridia. Importantly, we show for the first time that microbial communities from multiple LAs in one animal’s liver are highly similar, suggesting that abscesses found at different locations in the liver may originate from a localized source in the GIT (rather than disparate locations). A large portion of abscesses were dominated by microbial taxa that were most abundant in the hindgut. Further, we identified taxa throughout the GIT that were differentially abundant between animals with and without liver abscesses. Bifidobacterium spp.—a bacteria commonly associated with a healthy GIT in several species—were more abundant in the rumen and ileum of animals without LAs compared to those with LAs. Conclusions Together these results provide the first direct comparison of GIT and LA microbial communities within the same animal, add considerable evidence to the hypothesis that some LA microbial communities arise from the hindgut, and suggest that barrier dysfunction throughout the GIT may be the underlying cause of LA formation in cattle.

The role of microbial communities on beef color stability during retail display is not fully understood. Therefore, this study aimed to characterize the physiochemical properties and microbial communities of color-stable (longissimus lumborum [LL]) and color-labile (psoas major PM]) beef muscles during aerobic retail display. Paired USDA Select beef LL and PM (n=5) were collected and aged (at 2°C) for 14 d. These were fabricated into 2.54-cm-thick steaks, packaged aerobically, and subjected to 7 d of retail display. Samples were evaluated daily for visual and instrumental color, percent-age discoloration, water activity, pH, metmyoglobin reducing activity (MRA), and bacterial population levels using conventional culture-based methodologies. Additionally, 16S ribosomal RNA (rRNA) amplicon sequencing was performed to characterize microbial communities associated with the LL and PM steaks throughout storage. The percentage discoloration was greater (P

Extending the shelf life of fresh meat without having an adverse effect on its quality attributes is critical to the meat industry to reduce waste, stabilize supply, and facilitate export. Low temperature (LT) storage of beef muscles at or slightly above their freezing point slows down microbiological spoilage while maintaining the product’s fresh status.This study evaluated the impact of 60, 75, or 90 d of LT storage (−2.7°C±0.3°C) on the palatability characteristics of steaks from inside rounds (IR), bone-in ribeyes, and striploins (SL) from 10 (n=10) upper two-thirds Choice beef carcasses. Two steaks fabricated from each subprimal were vacuum-packaged, wet-aged for 21 d (3°C), and frozen (−20°C) for Warner-Bratzler shear force (WBSF) and sensory analyses. These steaks served as the control with regard to storage condition and time. The remainder of each subprimal was fabricated into 3 portions, vacuum packaged, and randomly allocated to an LT storage time (60, 75, or 90 d). After each storage time, subprimals were fabricated into steaks, vacuum-packaged, and stored (−20°C) for WBSF and consumer sensory analyses. Consumers (N=238) evaluated cooked samples for juiciness, tenderness, flavor liking, and overall liking. Data were analyzed using a mixed model with storage time as the fixed effect and individual carcasses as the random blocking factor. The WBSF values decreased (P

Purpose/Aim: Adverse drug reactions (ADRs) are significantly under-reported worldwide. The aim of this study was to assess the impact of educational interventions (EIs) on knowledge, attitude, and practice (KAP) of hospital resident doctors and faculty members and compare ADR reporting in EI (medical specialties) vs. non-EI (surgical specialties) in these two cadres of doctors. Materials and Methods: This study was a prospective comparative study conducted in two groups (EI and non-EI) in resident doctors and faculty members working at a tertiary care hospital. EI group (medical specialties) were provided with EI to increase awareness about ADR reporting, whereas in non-EI group (surgical specialties), no EI was provided and they served as control. Respondents were asked to fill a pretest questionnaire followed by interactive EI in EI group and posttest questionnaire in both groups. The impact of EI among respondents was evaluated by their response to questionnaire and number of ADRs reported after intervention. Results: Total (n = 202) respondents were enrolled in the study. The number of resident doctors and faculty members in each group were (n = 101 [50%]). Overall, (n = 100 [49.5%]) were from the medical and (n = 102 [50.5%]) from surgical specialty. Post-EI period, there was statistically significant improvement in KAP domains. Conclusion: Our study serves as credible evidence that through EI; statistically significant improvement in KAP of resident doctors and faculty members in both medical and surgical specialties toward ADR reporting and existing pharmacovigilance system can be achieved.

Rapid evaporative ionization mass spectrometry (REIMS) is a novel technique that provides rapid chemical information on biological tissues and has the potential to predict beef quality attributes in real time. This study aims to assess the ability of analysis by REIMS coupled with chemometric modeling to predict the quality attributes of wet-aged beef at the grading time. USDA Select and upper two-thirds Choice (n=42, N=84) striploins (longissimus lumborum [LL]) and tenderloins (psoas major [PM]) were collected 36 h postmortem from a commercial beef abattoir. The LL and PM were cut into portions and aged for 3, 14, and 28 d. Aged samples were analyzed for slice shear force,Warner-Bratzler shear force (WBS), and trained sensory panels (tenderness, juiciness, and flavor attributes), and results were used to categorize both LL and PM into binary classes. Additionally, slivers of the longissimus dorsi muscle between the 12th and 13th rib were collected during grading (36 h postmortem) and analyzed using REIMS. The REIMS data were used to build predictive models for tenderness, juiciness, and flavor classes for the 3 aging periods and 2 muscles. Prediction accuracies of all models were higher than classifying the samples by chance (P0.05). However, model accuracies were not too high, which could be due to overlaps between classes, small sample sizes, and unbalanced data, which could negatively affect predictive models. Results demonstrated that the chemical finger-prints obtained with REIMS could potentially sort carcasses by flavor, juiciness, and tenderness in real time. However, the full realization of this approach will require an increased sample size and the development of a sampling method that allows improved separation between sensory classes.

Background/Objectives: Early postmortem mitochondrial function and apoptotic activation affect meat quality development. Nicotinamide riboside (NR) supplementation to pigs prior to harvest can improve pork color stability, but its mechanism remains unclear. This study aimed to evaluate the impact of NR supplementation on early postmortem mitochondrial functionality and apoptosis. Methods: Sixteen pigs (N = 16) were individually fed a control or NR-supplemented diet (30 mg·kg body weight−1·d−1) for 10 days prior to harvest. Longissimus dorsi muscle samples were collected at 45 min and 24 h postmortem and analyzed for mitochondrial functionality using high-resolution respirometry and apoptotic protein abundance (apoptosis regulator Bcl-2-associated X (BAX), apoptotic inducing factor (AIF), and caspase 3 (CASP3)) via immunoblotting. Results: NR-supplemented muscle exhibited lower proton leak-associated respiration at 45 min postmortem (p < 0.05), followed by a slower accumulation of mitochondrial outer membrane permeabilization (MOMP; p < 0.05) and a slower loss of mitochondrial integral function (p < 0.05) from 45 min to 24 h postmortem. NR supplementation decreased BAX abundance at 45 min postmortem but increased mature AIF abundance (62 kDa) at 24 h postmortem (p < 0.05). The abundance of CASP3 fragments (~29 kDa) decreased from 45 min to 24 h postmortem, independent of treatment (p < 0.05). Conclusions: NR supplementation demonstrated the potential to protect mitochondrial integral function and alleviate apoptotic activation in early postmortem porcine skeletal muscle, which might contribute to a higher meat color stability in NR-supplemented pork during retail display. [ABSTRACT FROM AUTHOR]

Studies reporting on alternative antimicrobial interventions for pathogen control on chilled pork carcasses and cuts are limited. In this study, the antimicrobial effects of various spray treatments against Salmonella enterica inoculated on skin-on pork samples were evaluated. Chilled pork jowls were portioned (10 by 5 by 1 cm) and inoculated, on the skin side, with a mixture of six S. enterica serotype strains to target levels of 6 to 7 log CFU/cm2 (high inoculation level) or 3 to 4 log CFU/cm2 (low inoculation level). Samples were then left nontreated (control) or were treated (10 s) using a laboratory-scale spray cabinet with water, formic acid (1.5%), a proprietary blend of sulfuric acid and sodium sulfate (SSS, pH 1.2), peroxyacetic acid (PAA, 400 ppm), or PAA (400 ppm) that was pH-adjusted (acidified) with acetic acid (1.5%), formic acid (1.5%), or SSS (pH 1.2). Samples (n = 6) were analyzed for Salmonella populations after treatment application (0 h) and after 24 h of refrigerated (4°C) storage. Irrespective of inoculation level, all spray treatments effectively reduced (P

Meat color is an important aspect of a consumer’s purchase decisions regarding meat products. Perceived meatcolor results from the interaction of light, a detector (i.e., human eye), and numerous factors, both intrinsic and extrinsic tothe muscle, that influence the chemical state of myoglobin. The complex nature of these interactions dictates that decisionsregarding evaluations of meat color be made carefully and that investigators have a basic knowledge of the physical andchemical factors affecting their evaluations. These guidelines were compiled to aid investigators in navigating the pitfalls ofmeat color evaluation and ensure the reporting of information needed for the appropriate interpretation of the resulting data.The guidelines provide an overview of myoglobin chemistry, perceptions of meat color, details of instrumentation used inmeat color evaluation, and step-by-step protocols of the most common laboratory techniques used in meat color research.By following these guidelines, results of meat color research may be more clearly presented and more easily replicated.

A Multilayer network is a potent platform that paves the way for the study of the interactions among entities in various networks with multiple types of relationships. This study explores the dynamics of discrete-time quantum walks on a multilayer network. We derive a recurrence formula for the coefficients of the wave function of a quantum walker on an undirected graph with a finite number of nodes. By extending this formula to include extra layers, we develop a simulation model to describe the time evolution of the quantum walker on a multilayer network. The time-averaged probability and the return probability of the quantum walker are studied with Fourier, and Grover walks on multilayer networks. Furthermore, we analyze the impact of decoherence on quantum transport, shedding light on how environmental interactions may impact the behavior of quantum walkers on multilayer network structures.

Abstract The influence of the South American total solar eclipse of 14th December 2020 on the ionosphere is studied by using the continuous Chilean Global Positioning System (GPS) sites across the totality path. The totality path with eclipse magnitude 1.012 passed through the Villarrica (Lon. 72.2308°W and Lat. 39.2820°S) in south Chile during 14:41:02.0 UTC to 17:30:58.1 UTC and maximum occurred ~ 16:03:49.5 UTC around the local noon. The vertical total electron content (VTEC) derived by GPS sites across the totality path for two PRN’s 29 and 31 show almost 20–40% of reduction with reference to ambient values. The percentage reduction was maximum close to totality site and decreases smoothly on both sides of totality sites. Interestingly, the atmospheric gravity waves (AGWs) with a period ~ 30–60 min obtained using wavelet analysis of VTEC timeseries show the presence of strong AGWs at the GPS sites located north of the totality line. But the AGWs do not show any significant effect on the VTEC values to these sites. Our analysis suggests, possibly an interplay between variability in the background plasma density and eclipse-generated AGWs induced plasma density perturbation could explain the observations.

We theoretically analyze the case of noisy Quantum walks (QWs) by introducing four qubit decoherence models into the coin degree of freedom of linear and cyclic QWs. These models include flipping channels (bit flip, phase flip and bit-phase flip), depolarizing channel, phase damping channel and generalized amplitude damping channel. Explicit expressions for the probability distribution of QWs on a line and on a cyclic path are derived under localized and delocalized initial states. We show that QWs which begin from a delocalized state generate mixture probability distributions, which could give rise to useful algorithmic applications related to data encoding schemes. Specifically, we show how the combination of delocalzed initial states and decoherence can be used for computing the binomial transform of a given set of numbers. However, the sensitivity of QWs to noisy environments may negatively affect various other applications based on QWs.

Beef flavor has been identified as a driver of consumer acceptability; however, little is known about variability of flavor in major United States retail beef cuts. Four beef cuts (chuck roast; top sirloin steaks; top loin steaks; and 80/20 ground beef) were obtained from retail stores (n=30 per cut per city) in Miami, Los Angeles, Portland, New York, and Denver during a 2-mo period in 2018. Production systems or package claims were documented. An expert trained flavor and texture descriptive attribute sensory panel evaluated beef flavors, aromas, and textures (n=10 cuts per city or 50 cuts evaluated). Consumer sensory panels in Fort Collins, CO (n=10 per cut/city), and Lubbock, TX (n=10 per cut/city), evaluated beef for overall liking, overall flavor, beef flavor, grilled flavor, juiciness, and texture liking. Ground beef patties (GB) were more intense (P

Aging of beef subprimals is a common industry practice to improve tenderness. However, the effect of extended aging (up to 63 d) on retail shelf life, tenderness, and eating quality of beef strip loin and sirloin of differing quality grades is not clearly understood. Therefore, in the current study, longissimus dorsi (strip loin) and gluteus medius muscles (sirloin) were collected from USDA Choice or Select carcasses and fabricated into 6 portions. Each of these portions was designated to an assigned time of wet aging (14, 21, 28, 35, 45, or 63 d) in vacuum bags. After aging, samples were fabricated into steaks and placed into a multideck retail display case for 72 h. Steaks were evaluated for color (instrumental and color panelists) every 8 h during retail display, and Warner-Bratzler shear force and sensory analysis were conducted after retail display. The results were analyzed using the PROC MIXED procedure of SAS with repeated measures for the color data. Among the effects evaluated (aging, quality grade, and aging×quality grade), quality grade was not significant (P>0.05) for either strip loin or sirloin steaks. An aging×display hour interaction was identified (P

Abstract To unravel the relationship between earthquake and tsunami using ionospheric total electron content (TEC) changes, we analyzed two Chilean tsunamigenic subduction earthquakes: the 2014 Pisagua Mw 8.1 and the 2015 Illapel Mw 8.3. During the Pisagua earthquake, the TEC changes were detected at the GPS sites located to the north and south of the earthquake epicenter, whereas during the Illapel earthquake, we registered the changes only in the northward direction. Tide-gauge sites mimicked the propagation direction of tsunami waves similar to the TEC change pattern during both earthquakes. The TEC changes were represented by three signals. The initial weaker signal correlated well with Acoustic Rayleigh wave (AWRayleigh), while the following stronger perturbation was interpreted to be caused by Acoustic Gravity wave (AGWepi) and Internal Gravity wave (IGWtsuna) induced by earthquakes and subsequent tsunamis respectively. Inevitably, TEC changes can be utilized to evaluate earthquake occurrence and tsunami propagation within a framework of multi-parameter early warning systems.

The objective of this study was to characterize flavor, fatty acid composition, and volatile compounds of beef treated with common antimicrobial interventions in beef processing facilities. The effect of 3 prechilling antimicrobial interventions (4.5% lactic acid [LA]; 400 ppm peroxyacetic acid acidified to pH 1.2 with a sulfuric acid and sodium sulfate blend [aPAA]; or untreated control [CON]) and 4 postchilling treatments (CON; LA; aPAA; or a 2.5% solution of a commercial blend of lactic and citric acid [LAC]) were analyzed. Briskets (n = 30/treatment) were treated before and after chilling using a custom-built pilot-sized spray cabinet, ground twice, and formed into patties. Cooked patties were analyzed by a trained sensory panel, and a subset of raw samples (n = 6) were analyzed for fatty acid composition and volatile compounds. Samples treated with LA before and after chilling were more intense in sourness than the CON (P < 0.05). Fatty acid analysis showed no differences (P > 0.05) due to the use of chemical interventions. Only postchilling treatments had an effect on volatile compounds. The relative abundances of pentanal and pentanol were greater (P < 0.05) in LA-treated postchilling intervention samples than CON and LAC, hexanoic acid was greater (P < 0.05) in aPAA than CON and LAC, and acetic acid was greater (P < 0.05) in aPAA than LAC. Overall, these results demonstrated that LA pre- and postchilling antimicrobial interventions only impact the sourness of ground beef but did not affect the fatty acid composition, while postchilling antimicrobial treatments had a minimal impact on volatile compounds.

If left unrepaired, meiotic DSBs are toxic to mammalian cells, thus oocytes in which DSBs persist are eliminated by the DNA-damage checkpoint. Here the authors provide insights into the roles of PUMA, NOXA and BAX during DNA damage checkpoint that eliminates Dmc1 −/− and Msh5 −/− oocytes.

Any deviation from a bright-red color leads to a discounted price or beef is discarded. Limited data are currently available on the economic losses due to retail beef discoloration. Therefore, the objective of the study was to estimate economic losses, the amount of beef discarded, natural resource wastage, and environmental impact due to beef discoloration. One-year data of total beef sales, total beef discarded, and discounted sale values were collected from 2 national retail chains and 1 regional retail chain located in the Southern United States, representing data from 5,034 stores and 44 states. The US beef system life cycle parameters from published literature were used to calculate the impact of discarded meat on water and energy use and greenhouse gas emissions. The study noted that approximately 2.55% of beef is discarded because of discoloration. The results indicate that the US beef industry loses $3.73 billion annually owing to discoloration. The total amount of beef discarded per year in the US corresponds to 194.70 million kg, which represents wasting 780,000 animals and the associated natural resources used in their production. A 1% decrease in discolored beef in the US could reduce natural resource waste and environmental impact by 23.95 billion L of water, 96.88 billion MJ of energy consumed, and 0.40 million tons of carbon dioxide equivalent emission along the beef upstream value chain. Therefore, improving the color stability of meat could increase the sustainability of beef production and limit the waste of nutritious beef, so the application of novel technologies to mitigate color deterioration should be imperative.

Variability in carcass size can influence carcass chilling rates, which could result in issues associated with beef tenderness and color. Moreover, the usage of electrical stimulation can affect postmortem metabolism and meat quality. However, few studies have looked at the combined impact of chilling and electrical stimulation on temperature decline, postmortem biochemistry, and color among the current population of US beef. Beef carcasses (N = 162, < 30 mo) were randomly selected from 2 beef processing plants. One side of each carcass was electrically stimulated, while the opposing side was not electrically stimulated. Matched sides were subjected to either conventional spray chilling (CONV) or delayed spray chilling (DELAY). Deep tissue (10.5 cm under the pelvic bone) and surface temperature (1.5 cm under the loin fat) were continuously monitored during chilling in addition to temperature and pH measurements from the semimembranosus (SM), longissimus lumborum (LL), and psoas major (PM) muscles at an initial time (45 to 60 min), 6 h, 12 h, and after chilling (28 to 36 h) postmortem. Further, the instrumental (L*, a*, and b*) and visual color were evaluated on 14-d aged PM steaks. For data analysis, carcasses with hot carcass weights above or below the plant average were considered heavy or light, respectively. A nonlinear regression model was fitted to the continuous deep and surface temperatures, whereas other parameters were evaluated using a mixed model. Electrical stimulation improved L* (lightness; P < 0.05) of PM in light- weight carcasses but not (P > 0.05) in heavyweight carcasses. Temperature decline was faster (P < 0.05) and pH decline slower (P < 0.05) in the SM and LL of lightweight carcasses under CONV compared to lightweight carcasses under DELAY and heavyweight carcasses under CONV and DELAY. Exponential decay models for deep and surface temperatures indicated the rate of cooling differed (P < 0.05) due to the combination of treatment factors. Heavyweight carcasses in DELAY had slower rates of temperature decline (P < 0.05). Overall, the variability in carcass size affected temperature decline and postmortem metabolism. Therefore, postmortem management practices should consider carcass weights to optimize meat quality.

Author(s): Shantha K. Mahadevaiah [sup.1] , Mahesh N. Sangrithi [sup.2] [sup.3] , Takayuki Hirota [sup.1] , James M. A. Turner [sup.1] Author Affiliations: (1) Sex Chromosome Biology Laboratory, The Francis [...], Single-cell RNA sequencing of embryos can resolve the transcriptional landscape of development at unprecedented resolution. To date, single-cell RNA-sequencing studies of mammalian embryos have focused exclusively on eutherian species. Analysis of mammalian outgroups has the potential to identify deeply conserved lineage specification and pluripotency factors, and can extend our understanding of X dosage compensation. Metatherian (marsupial) mammals diverged from eutherians around 160 million years ago. They exhibit distinctive developmental features, including late implantation.sup.1 and imprinted X chromosome inactivation.sup.2, which is associated with expression of the XIST-like noncoding RNA RSX.sup.3. Here we perform a single-cell RNA-sequencing analysis of embryogenesis and X chromosome inactivation in a marsupial, the grey short-tailed opossum (Monodelphis domestica). We resolve the developmental trajectory and transcriptional signatures of the epiblast, primitive endoderm and trophectoderm, and identify deeply conserved lineage-specific markers that pre-date the eutherian-marsupial divergence. RSX coating and inactivation of the X chromosome occurs early and rapidly. This observation supports the hypothesis that--in organisms with early X chromosome inactivation--imprinted X chromosome inactivation prevents biallelic X silencing. We identify XSR, an RSX antisense transcript expressed from the active X chromosome, as a candidate for the regulator of imprinted X chromosome inactivation. Our datasets provide insights into the evolution of mammalian embryogenesis and X dosage compensation. Single-cell RNA-sequencing analysis of embryogenesis and X chromosome inactivation in the opossum (Monodelphis domestica) resolves the developmental trajectory of a marsupial, and sheds light on the evolution of embryogenesis in mammals.

Advancements in technology and analytical methods enable researchers to explore the biochemical events that cause variation in meat quality. Among those, western blot techniques have been successfully used in identifying and quantifying the key proteins that have critical functions in the development of meat quality. Housekeeping proteins, like β-actin, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and tubulins are often used as internal controls in western blots to normalize the abundance of the protein of interest. However, there are increasing concerns about using housekeeping proteins for western blot normalization, as these proteins do not demonstrate any loading differences above the relatively small total protein loading amounts of 10μg. In addition, the interaction between these housekeeping proteins and programmed cell death processes highlights the concerns about using the housekeeping protein as the internal control in meat quality research. Moreover, recent proteomic research has indicated that the abundance of some housekeeping proteins, like β-actin, GAPDH, and tubulin, can be altered by preslaughter stress, dietary supplementation, sex, slaughter method, genotype, breed, aging period, muscle type, and muscle portion. Furthermore, these housekeeping proteins could have differential expression in meat with differing color stability, tenderness, and water holding capacity. Therefore, this review aims to examine the realities of using housekeeping proteins as the loading control in meat quality research and introduce some alternative methods that can be used for western blot normalization.

Iron is an essential mineral that supports biological functions like growth, oxygen transport, cellular function, and hormone synthesis. Insufficient dietary iron can lead to anemia and cause fatigue, cognitive impairment, and poor immune function. Animal-based foods provide heme iron, which is more bioavailable to humans, while plant-based foods typically contain less bioavailable non-heme iron. Edible insects vary in their iron content and may have heme or non-heme forms, depending on their diet. Edible insects have been proposed as a protein source that could address issues of food insecurity and malnutrition in low resource contexts; therefore, it is important to understand the bioavailability of iron from insect-based foods. In this study, we used Inductively Coupled Plasma and Mass Spectrometry (IPC-MS) and Caco-2 cell culture models to compare the soluble and bioavailable iron among five different lab-produced tempeh formulations featuring Tenebrio molitor (mealworm) with their non-fermented raw ingredient combinations. Finally, we compared the iron bioavailability of a mealworm tempeh with two sources of conventional beef (ground beef and sirloin steaks) and two commercially available plant-based meat alternatives. The results show that while plant-based meat alternatives had higher amounts of soluble iron, particularly in the Beyond Burger samples, the fermented mealworm-based tempeh had greater amounts of bioavailable iron than the other samples within the set. While all the samples presented varying degrees of iron bioavailability, all products within the sample set would be considered good sources of dietary iron. [ABSTRACT FROM AUTHOR]