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PCBoom propagation simulations of the NASA X-59 low-boom in supersonic cruise were conducted using near-field CFD pressure waveforms as inputs to estimate the noise dose range. Low-booms were propagated through realistic atmospheric profiles from the Climate Forecast System Version 2 across the USA, and loudness statistics of the low-booms are presented. The near-field waveforms correspond to aircraft configurations expected to produce minimum- and maximum-loudness levels on the ground. The simulations show that the practical Perceived Level noise dose range is 72 to 86.7 dB. Dose ranges for other single event and cumulative sonic boom metrics of interest are also provided.
Reduction in skeletal muscle mass, strength, and function, such as sarcopenia, have been associated with cognitive impairment. In Latin America (LATAM), evidence remains scarce, a critical gap given the region rapid demographic aging. Therefore, the present study aims to evaluate the association between sarcopenia and cognitive impairment among middle-aged and older adults in LATAM countries. A systematic review and meta-analysis. A systematic literature search was conducted using PubMed, Web of Science, EMBASE, LILACS, SciELO and sources of grey literature. The association between sarcopenia and cognitive impairment (odds ratio) was pooled in a meta-analysis using a random-effects model. The quality of the methodology used in each study was evaluated using the JBI Critical Appraisal Tools. Middle-aged and older adults from cross-sectional and longitudinal studies conducted in Latin American populations. The primary outcome was the pooled association between sarcopenia and cognitive impairment. A total of 8 studies and 13,395 community-dwelling adults were included. The meta-analysis showed that sarcopenia was associated with higher odds of cognitive impairment (OR = 2.30; 95% CI: 1.68-3.15). However, the magnitude of this association varied according to definition as probable cognitive impairment (OR = 2.56, 95% CI: 1.85-3.53, P < 0.001) and diagnosis criteria of sarcopenia by EWGSOP2 (OR = 2.96; 95% CI: 2.15-4.08, P < 0.001). In LATAM, sarcopenia doubles the odds of cognitive impairment in adults. Future research must elucidate the inflammatory, oxidative, and mitochondrial pathways linking muscle and brain health.
During NASA X-59 quiet supersonic aircraft community response tests, low-boom recordings will contain contaminating noise from instrumentation and ambient acoustical sources. This noise can inflate sonic boom perception metrics by several decibels. This paper discusses the development and comparison of robust lowpass filtering techniques for removing contaminating noise effects from low-boom recordings. The two filters are a time-domain Butterworth-magnitude filter and a frequency-domain Brick Wall filter. Both filters successfully reduce noise contamination in metric calculations for simulated data with real-world contaminating noise and demonstrate comparable performance to a modified ISO 11204 correction. The Brick Wall filter's success indicates that further attempts to match boom spectrum high-frequency roll-off beyond the contaminating noise floor are unnecessary and have marginal improvements on final metric calculations. Additionally, the Butterworth filter removes statistical correlation between ambient and boom levels for a real-world flight campaign, adding evidence that these techniques also work on other boom shapes. Overall, both filters can produce accurate metric calculations with only a few hundred hertz of positive signal-to-noise ratio. This work describes methods for accurate metric calculations in the presence of moderate noise contamination that should benefit X-59 and future low-boom supersonic aircraft testing.
It is well established that the gut-brain axis (GBA) is a bidirectional communication between the gut and the brain. This axis, critical in maintaining overall homeostasis, is regulated at the neuronal, endocrine, and immunological levels, all of which may be influenced by the gut microbiota (GM). Therefore, dysbiosis or disruption in the GM may have serious consequences including neuroinflammation due to overactivation of the immune system. Strategies to reestablish GM integrity via use of probiotics are being pursued as novel therapeutic intervention in a variety of central and peripheral diseases. The mechanisms leading to dysbiosis or efficacy of probiotics, however, are not fully evident. Here, we performed computational analysis on two major probiotics, namely Lactobacillus Lacticaseibacillus rhamnosus GG (formerly named Lactobacillus rhamnosus, L. rhamnosus GG) and Bifidobacterium animalis spp. lactis (B. lactis or B. animalis) to not only shed some light on their mechanism(s) of action but also to identify potential molecular targets for novel probiotics. Using the PubMed web page and BioCyc Database Collection platform we specifically analyzed proteins affected by metabolites of these bacteria. Our results indicate that peroxisome proliferator-activated receptors (PPARs), nuclear receptor proteins that are involved in regulation of inflammation are key mediators of the neuroactive effect of probiotics.
Physical activity (PA) is associated with better quality of life for cancer survivors; however, less is known about this association among individuals with advanced cancer. This study assesses whether changes in PA following an advanced cancer diagnosis are associated with health-related quality of life (HRQoL) outcomes. Data were collected from 247 participants in a survey of adults with advanced cancer who visited the University of Wisconsin Carbone Cancer Center (January 2021-2023). PA since cancer diagnosis was assessed using a validated, self-reported tool. HRQoL was assessed using the Functional Assessment of Cancer Therapy - General and Patient-Reported Outcomes Measurement Information System measures of physical function, fatigue, and pain interference. We used generalized linear models to assess relationships between PA and HRQoL. Most adults with advanced cancer were insufficiently active (53%), and reported a lot less activity (41%) after diagnosis, followed by a little less activity (33%), and the same/more activity (26%). Compared to the other activity groups, those who reported a lot less activity had the worst HRQoL scores, including lower HRQoL (x̄ = 70.3 vs. x̄ = 82.6, 90.7) and physical function (x̄ = 40.3 vs. x̄ = 47.3, 52.5), and higher fatigue (x̄ = 59.3 vs. x̄ = 51.4, 42.3) and pain interference (x̄ = 55.5 vs. x̄ = 48.8, 45.6). Adults with advanced cancer who report PA reductions have worse HRQoL, higher pain and fatigue, and lower physical function than those engaging in the same/more PA since their diagnosis. Future interventions focused on improving HRQoL among adults with advanced cancer should incorporate light-intensity PA to reduce declines following diagnosis.
Background/Objectives: Rubinstein-Taybi Syndrome (RSTS-OMIM, #180849) is a rare genetic disorder associated with distinctive clinical features, including a typical craniofacial appearance, global developmental delay, intellectual disability and broad, angular thumbs and fingers. The main aim of the study was to evaluate the health problems of children with RTST, their quality of life and the impact of the disease on family functioning. In addition, we investigate whether comorbidities, autistic behavior and eating problems affect the children's overall QOL. Methods: A cross-sectional study was performed, including a total of 13 caregivers of children diagnosed with RSTS. A self-reported questionnaire [SRQ], medical records and the Pediatric Impact Module PedsQLTM 2.0, the Pediatric Quality of Life PedsQLTM 4.0 were used to obtain data on QOL and the impact of the disease on family functioning. Results: The overall QOL score for children with RSTS was x = 52.40; SD 13.01. The highest QOL was in emotional functioning (EF; x = 59.23; SD 18.69), while the lowest QOL was in physical functioning (PF; x = 48.56; SD 16.32) and social functioning (SF; x = 48.85; SD 18.84). There was a statistically significant negative correlation (p < 0.03; r = -2.01) between the age of the child and their QOL, indicating that older children had lower QOL scores. The mean overall rating for the impact of RSTS on family functioning was x = 50.00; SD 10.91. Caregivers reported the highest scores for cognitive functioning (CF; x = 64.23; SD 23.70) and family relationships (FR; x = 60.00; SD 17.17). The lowest scores were for daily activities (DA; x = 41.03; SD 17.17) and worry (W; x = 37.69; SD 18.55). Conclusions: This study provides the first comprehensive exploration of the QOL of children with RSTS) and its impact on family functioning.
To explore the genetic characteristics of a fetus with sex chromosome abnormality indicated by non-invasive prenatal testing (NIPT) at 25+ gestational weeks. A pregnant woman who was admitted to the Taizhou Hospital for abnormal NIPT result on January 6, 2023 was selected as the study subject. Relevant clinical data was collected. The fetus was subjected to chromosomal karyotyping analysis, copy number variation sequencing (CNV-seq), fluorescence in situ hybridization (FISH), and multiplex PCR assays. NIPT had suggested monosomy of X chromosome. The fetus was found to have a chromosomal karyotype of 45,X[59]/46,X,del(Y)(q11.2)[17] at 30+ weeks of gestational age. CNV-seq suggested the presence a 7.98 Mb deletion at Yq11.222q12 and a mosaicism 16.92 Mb deletion. FISH suggested that the fetus harbored two SRY genes and a mosaicism sex chromosomal abnormality, and multiplex PCR revealed that its AZF b+c region was completely deleted. C-banded karyotyping showed darkly stained dense mitotic granules at both ends of the Y chromosome. The fetus was ultimately determined as a 45,X/46,X,idic(Y)(q11.2) mosaicism. Following elected abortion, testing of the fetal tissue confirmed the presence of 45,X/46,XY mosaicism, and CNV-seq result of the placental tissue was compatible with that of NIPT. CNV-seq analysis of the couple revealed no obvious abnormality. With combined NIPT, karyotyping, CNV-seq, FISH and multiplex PCR assays, the fetus was diagnosed as a 45,X/46,X,idic(Y)(q11.2) mosaicism with deletion of the AZF b+c region. Above finding has enabled prenatal diagnosis for the fetus.
The use of various hemp-derived products has been rapidly growing in the human nutrition industry and has sparked great interest in using these ingredients for companion animals as well. Thorough research is needed to determine the ingredient and safety standards required for AAFCO approval of hemp ingredients. In order to be effectively incorporated into pet food products, we must determine the nutrient content, quality, and utility of these ingredients in pet species. The objective of this study was to evaluate the nutrient composition of seeds from four different varieties of hemp, NWG 452, NWG 331, NWG 2730, X-59, and determine protein quality and true metabolizable energy using a cecectomized rooster model. The seeds were similar in macronutrient composition, with small variations in acid hydrolyzed fat, crude protein, total dietary fiber and gross energy content, as well as amino acid and long-chain fatty acid profiles. All essential amino acids were present in concentrations that exceeded the NRC (2006) recommended allowances for adult dogs and cats at maintenance with the exception of tryptophan. The long-chain fatty acid profile presented a favorable ratio of omega-6 to omega-3 fatty acids of close to 3.5:1. The results of the cecectomized rooster assay indicated no significant difference in the standardized amino acid digestibility of the indispensable amino acids among the seed varieties (P > 0.05). A significant difference in the true metabolizable energy corrected for nitrogen was observed among the seeds (P < 0.05), following the pattern of higher acid hydrolyzed fat and lower total dietary fiber content resulting in higher metabolizable energy. An adapted calculation of digestible indispensable amino acid score was made to determine protein quality of the hemp seeds using AAFCO nutrient profiles and NRC recommended allowances for adult dogs and cats at maintenance as reference points. The resulting scores determined tryptophan to be the first limiting amino acid and indicate that hemp seeds alone do not meet all the amino acid requirements for adult dogs and cats at maintenance, and would need a complimentary protein source for practical use in companion animal diets. The data from this study suggest that hemp seeds may provide a beneficial source of fat, protein, and dietary fiber, with consideration to differences in nutrient profile among seed varieties. However, further investigation in vivo is needed to determine the safety and efficacy of utilizing hemp in the diets of both canines and felines. Hemp products have become popular in the human food and health industry over the past few years. Due to this, a growing interest in using hemp ingredients in animal products has developed as well. There is a need to investigate the nutritional properties and potential utility of hemp seeds in food products for companion animals in order for them to be consumed safely and effectively. Four different varieties of hemp seed were evaluated and found to have similar fat, fiber, and protein content as well as protein quality. The results indicate that hemp seeds may be an advantageous ingredient in the development of pet food products, but a more in depth evaluation using pet species is necessary to confirm this.
Optic neuritis (ON), a major cause of visual impairment in young adults, is generally associated with rapid visual recovery when treated with intravenous methylprednisolone treatment (IVMPT). However, the optimal duration of such treatment is unknown, ranging from three to seven days in clinical practice. We aimed to compare the visual recovery in patients treated with 5-day or 7-day duration IVMPT. We performed a retrospective cohort study of consecutive patients with ON in São Paulo, Brazil, from 2016 to 2021. We compared the proportion of participants with visual impairment in 5-day and 7-day treatment schedules at discharge, at 1 month and between 6 and 12 months after the diagnosis of ON. The findings were adjusted to age, severity of the visual impairment, co-intervention with plasma exchange, time from symptom onset to IVMPT and the etiology of the ON to mitigate indication bias. We included 73 patients with ON treated with 5 or 7-day duration of 1 g/d intravenous methylprednisolone therapy. Visual impairment at 6-12 months in the 5-day or the 7-day treatment groups was similar (57% x 59%, p > 0.9, Odds Ratio 1.03 [95% CI 0.59-1.84]). The results were similar after adjusting for prognostic variables and when observed at different time points. Visual recovery is similar in patients treated with 5-day and 7-day duration treatments of 1 g/day intravenous methylprednisolone, suggesting a ceiling effect. Limiting the duration of the treatment can reduce hospital stay and costs, without interfering with clinical benefit.
The graft bending angle created by the graft and the tibial tunnel has inevitably occurred during the transtibial posterior cruciate ligament (PCL) reconstruction. However, few studies quantitively analyzed this angle. This study aimed to (I) explore the optimal tibial tunnel placement to maximize the graft bending angle in the PCL reconstruction; (II) reveal the effect of the tibial tunnel placement on the graft bending angle. This was an in-vitro surgical simulation study based on the three-dimensional (3D) computed tomography (CT). A total of 55 patients who took CT scanning for knee injuries were selected (April 2020 to January 2022) from the local hospital database for review. The 3D knee models were established on the Mimics software based on the knees' CT data. Using the Rhinoceros software to simulate the transtibial PCL reconstruction on the 3D CT knee model. The anteromedial and anterolateral tibial tunnel approaches were simulated with different tibial tunnel angle. The graft bending angle and tibial tunnel length (TTL) with different tibial tunnel angles were quantitively analyzed. The graft bending angle in anterolateral approach with a 50° tibial tunnel angle was significantly greater than it in anteromedial approach with a 60° tibial tunnel angle (P<0.001). There was no difference of the graft bending angle between the anterolateral approach with a 40° tibial tunnel angle and the anteromedial approach with a 60° tibial tunnel angle (P>0.05). The graft bending angle showed a strong correlation with the tibial tunnel angle (for anteromedial approach: r=0.759, P<0.001; for anterolateral approach: r=0.702, P<0.001). The best-fit equation to calculate the graft bending angle based on the tibial tunnel angle was Y = 0.89*X + 59.05 in anteromedial tibial tunnel approach (r2=0.576), and was Y = 0.78*X + 80.21 anterolateral tibial tunnel approach (r2=0.493). The graft bending angle and TTL will significantly increase as the tibial tunnel angle becomes greater. Maximizing the tibial tunnel angle (50° tibial tunnel angle) in the anterolateral approach could provide the greatest graft bending angle in the PCL reconstruction. No matter how the tibial tunnel angle is changed in the anteromedial approach, using anterolateral approach might reduce the killer turn effect more effectively than using anteromedial approach.
Sonic boom measurements from recent flight tests have provided an opportunity to investigate effects of microphone installation on sonic boom waveforms, spectra, and metric levels in support of NASA X-59 flight test planning. While those flight tests used N-wave aircraft (F-18s), modeling studies were also conducted using source characteristics for a shaped low-boom aircraft. Of particular interest were the effects of receiver height on boom waveforms and metrics at elevated receiver positions, microphone installation, and local ground cover type. Reductions of more than 2 dB in A-weighted sound exposure level and perceived level were shown for 1.6 ft (0.48 m) microphone heights for 35º ray elevation angle. Measured and modeled results are described in this letter.
The effects of a kinematic field of velocity fluctuations on the loudness metrics of two waveforms are examined with a three-dimensional one-way propagation solver. The waveforms consist of an N-wave and a simulated low-boom from NASA's X-59 QueSST aircraft. The kinematic turbulence is generated using a von Kármán composite spectrum, which is dependent on a root mean square (rms) velocity and outer scale of the turbulence. A length scale is proposed to account for the effect of the rms velocity and integral scale on the focusing and defocusing of the sonic boom waveform. The probability density function of the location of the first caustic attains a maximum value when the propagation distance is equal to the proposed length scale. Simulation results indicate that for small values of the nondimensional propagation distance, the standard deviation of the loudness metrics increases linearly. The loudness metrics follow a normal distribution within a given range of the nondimensional propagation distance. Results indicate the potential to parameterize the loudness metric distributions by the rms velocity and integral length scale.
Gut dysbiosis is considered a risk factor for Parkinson's disease (PD), and chronic treatment with probiotics could prevent it. Here we report the assessment of a probiotic mixture [Lacticaseibacillus rhamnosus GG (LGG), and Bifidobacterium animalis lactis BB-12 (BB-12)] administered to male rats 2 weeks before and 3 weeks after injecting 6-hydroxydopamine (6-OHDA) into the right striatum, a model that mimics the early stages of PD. Before and after lesion, animals were subjected to behavioral tests: narrow beam, cylinder test, and apomorphine (APO)-induced rotations. Dopaminergic (DA) denervation and microglia recruitment were assessed with tyrosine hydroxylase (TH+) and ionized calcium-binding protein-1 adapter (Iba1+) immunostaining, respectively. Post 6-OHDA injury, rats treated with sunflower oil (probiotics vehicle) developed significant decrease in crossing speed and increases in contralateral paw slips (narrow beam), forepaw use asymmetry (cylinder), and APO-induced rotations. In striatum, 6-OHDA eliminated ≈2/3 of TH+ area and caused significant increase of Iba1+ microglia population. Retrograde axonal degeneration suppressed ≈2/5 of TH+ neurons in the substantia nigra pars compacta (SNpc). In hemiparkinsonian rats, probiotics treatment significantly improved the crossing speed, and also reduced paw slips (postlesion days 14 and 21), the loss of TH+ neurons in SNpc, and the loss of TH+ area and of Iba1+ microglia count in striatum, without affecting the proportion of microglia morphological phenotypes. Probiotics treatment did not attenuate forepaw use asymmetry nor APO-induced rotations. These results indicate that the mixture of probiotics LGG and BB-12 protects nigrostriatal DA neurons against 6-OHDA-induced damage, supporting their potential as preventive treatment of PD.
Purpose: Individuals who subscribe to a color-blind racial ideology may not be aware of differences or differential treatment based on race which may be related to racial inequality in the delivery of oral health care. The purpose of this study was to determine color-blind racial attitudes in a convenience sample of clinical dental hygienists.Methods: A convenience sample of practicing dental hygienists recruited through social media via snowball sampling was invited to participate in this cross-sectional survey study. The Color-Blind Racial Attitudes Scale (CoBRAS), a valid and reliable measuring instrument, was used to determine unawareness of racial attitudes and stereotyping. Three subscales (Racial Privilege, Institutional Discrimination, and Blatant Racial Issues) were measured by the survey. Descriptive statistics and separate one-way between-subjects ANOVA were used to analyze the data.Results: Two-hundred and thirty-three (n = 233) dental hygienists in clinical practice completed the survey. ANOVA revealed statistically significant differences in overall CoBRAS scores when comparing age groups and ethnicities. Participants aged 18-29 had significantly lower overall CoBRAS scores compared to participants aged 60 and over (x = 49.41, x = 59.17, respectively; p = .019). African American participants scored significantly lower on overall CoBRAS scores compared only to those in the Other ethnicity category (x = 42.27, x = 62.08, respectively; p = .029).Conclusion: Participants possessed moderate levels of color-blindness, suggesting unawareness of racism and a need to understand the implications of racism as a means of promoting equity and improve oral health care delivery. Findings emphasize a need for more research examining color-blind ideology and how it affects oral health care delivery to diverse patient populations.
To provide an insight of the incidence of congenital developmental dysplasia of the hip in newborns from Yucatan born between 2015 and 2019 and analyze its association with maternal sociodemographic characteristics and neonatal, pregnancy and delivery related aspects. Retrospective, population-based study from Birth Registries database in Yucatan, Mexico between 2015 and 2019. Presence of hip dysplasia was described and analyzed considering three aspects (I) Maternal information (II) Pregnancy and birth (III) Neonatal examination. We obtained incidence rates from each year and the complete studied period. Association between hip dysplasia and maternal, neonatal and pregnancy/delivery variables was analyzed using logistic regression, unadjusted odds ratio and an adjusted model. Hip dysplasia occurred in 13 per 10 000 live births. Significant associations were found between hip dysplasia and maternal place of residence in a city <50 000 inhabitants, without a local clinic. Propensity to give birth to a neonate with hip dysplasia increased with maternal age and ethnicity, in female newborns and when total number of pregnancy consultations summed <5. Newborns with hip dysplasia were heavier and less susceptible to be delivered vaginally. Congenital developmental hip dysplasia was comparatively more frequent among offspring of Mayan women and suboptimal access to medical care during pregnancy. Female neonates were affected the most, those first-borns. Neonates with hip dysplasia were heavier and more susceptible to be born by cesarean section. Maternal, neonatal, and perinatal factors are associated with DDH in Yucatecan infants born during 2015-2019. Factors that describe living conditions seems to have a more important effect on the presence of this condition.
Environmental changes triggered by deforestation, urban expansion and climate change are present-day drivers of the emergence and reemergence of leishmaniasis. This review describes the current epidemiological scenario and the feasible influence of environmental changes on disease occurrence in the state of Yucatan, Mexico. Relevant literature was accessed through different databases, including PubMed, Scopus, Google, and Mexican official morbidity databases. Recent LCL autochthonous cases, potential vector sandflies and mammal hosts/reservoirs also have been reported in several localities of Yucatan without previous historical records of the disease. The impact of deforestation, urban expansion and projections on climate change have been documented. The current evidence of the relationships between the components of the transmission cycle, the disease occurrence, and the environmental changes on the leishmaniasis emergence in the state shows the need for strength and an update to the intervention and control strategies through a One Health perspective.
During 2007-2010, we examined which container types in Mérida, México, are most productive for Aedes aegypti (L.) immatures. Surveys for mosquito immatures followed routine surveillance methodology and container type classifications used by Servicios de Salud de Yucatán. Our main findings were that (1) small and larger discarded containers that serve no particular purpose and therefore can be removed from the environment contribute strongly to larval and pupal production in Mérida, and (2) the importance of different container types can vary among sets of residential premises as well as between dry and wet periods. These results may help to guide future implementation in Mérida of control efforts that target the most productive container types for Ae. aegypti immatures. Furthermore, if the Patio Limpio cleanup campaign that currently is ongoing in Mérida proves successful in removing discarded containers as important immature development sites, then we should see dramatic changes in the most productive container types in the future as the mosquito is forced to switch to other container types, which perhaps also will be easier to include in highly targeted mosquito control interventions.
In order to determine the in vivo activity against the protozoan Trypanosoma cruzi, two doses (50 and 75 mg/kg) of a chloroform extract of Carica papaya seeds were evaluated compared with a control group of allopurinol. The activity of a mixture of the three main compounds (oleic, palmitic and stearic acids in a proportion of 45.9% of oleic acid, 24.1% of palmitic and 8.52% of stearic acid previously identified in the crude extract of C. papaya was evaluated at doses of 100, 200 and 300 mg/kg. Both doses of the extracts were orally administered for 28 days. A significant reduction (p < 0.05) in the number of blood trypomastigotes was observed in animals treated with the evaluated doses of the C. papaya extract in comparison with the positive control group (allopurinol 8.5 mg/kg). Parasitemia in animals treated with the fatty acids mixture was also significantly reduced (p < 0.05), compared to negative control animals. These results demonstrate that the fatty acids identified in the seed extracts of C. papaya (from ripe fruit) are able to reduce the number of parasites from both parasite stages, blood trypomastigote and amastigote (intracellular stage).
This study investigated carbohydrate ingestion of varied doses and frequencies during a simulated cross-country skiing time trial. Ten men and three women (age: 30 ± 7 years; V ˙ O 2 m a x : 59.6 ± 5.7 mL/kg/min) completed four, 30-km classic technique roller skiing time trials on a treadmill. A 1:1 maltodextrin-fructose carbohydrate solution was provided at high (2.4 g/min; HC) and moderate (1.2 g/min; MC) ingestion rates, each at high (six feeds; HF) and low (two feeds; LF) frequencies. In the LF trials, blood glucose was elevated following carbohydrate ingestion (at 4 and 19 km) but was reduced at 14 and 29 km compared with HF strategies (P ≤ 0.05). Gastrointestinal discomfort was higher in HC-LF compared with all other trials (P ≤ 0.05). Whole-body lipid oxidation was lower and carbohydrate oxidation was higher in LF compared with HF trials (P ≤ 0.05). While performance time was not significantly different between trials (140:11 ± 15:31, 140:43 ± 17:40, 139:12 ± 15:32 and 140:33 ± 17:46 min:s in HC-HF, HC-LF, MC-HF, and MC-LF, respectively; P > 0.05), it was improved with trial order (P < 0.001). There was no effect of order on any other variable (P > 0.05). Altering carbohydrate dose or frequency does not affect cross-country ski performance. However, low-frequency carbohydrate ingestion resulted in poorer maintenance of euglycemia, reduced lipid oxidation, and increased gastrointestinal discomfort.
The aim of this study was to provide information of the occurrence of Rickettsia felis in wild mammals from three municipalities in Yucatan, Mexico. The reactivity of rodent serum to Rickettsia antigens was detected in 80.9% (17 of 21) samples using immunofluorescence assay. Polymerase chain reaction identified rickettsial DNA in spleens of 43.5% (10 of 23) rodents and 57.1% (4 of 7) opossums. The identification of the rickettsial DNA was confirmed as R. felis by restriction fragment length polymorphism and DNA sequencing. This study comprises the first report of R. felis detection in wild mammals in Yucatan.