Hibernating ground squirrels rely on a short active period for breeding and mass accrual, and are thus vulnerable to extreme climate events that affect key periods in their annual cycle. Here, we ...document how a heatwave in March 2012 led to a phenological mismatch between sexes in Richardson's ground squirrels (Urocitellus richardsonii). Females emerged from hibernation and commenced breeding earlier in 2012 relative to average female emergence. Although males had descended testes and pigmented scrota, it appeared that not all males were physiologically prepared to breed since 58.6% of males had non-motile sperm when breeding commenced. Body condition, relative testes size, and the relative size of accessory glands were significant predictors of sperm motility. Males with non-motile sperm had smaller accessory glands than males with motile sperm. There was no decrease in the number of juveniles that emerged in 2012 or female yearlings recruited in 2013, nor did juveniles emerge later than other years. The impact of this heatwave on male ground squirrels emphasizes the importance of assessing the consequences of climate change on the breeding success of hibernating species in both sexes, since the different sensitivity to external cues for emergence led to a mismatch in timing under this event.
The aim of this study was to assess bone changes and mobility in temporomandibular joints (TMJs) using cone beam CT (CBCT) in a population sample in Recife, PE, Brazil.
The TMJ images of patients ...treated by a radiologist at a private dental radiology service over a period of 1 year were retrieved from the computer database and assessed using a computer with a 21-inch monitor and the iCAT Cone Beam 3D Dental Imaging System Workstation program (Imaging Sciences International, Hatfield, PA). The Pearson χ(2) test was used to analyse the differences in percentage of bone changes among the categories of mobility (p ≤ 0.05). The McNemar test was used to compare the presence of bone changes in TMJs on the right and left sides (p ≤ 0.05).
An adjusted logistic regression model was used to assess the effect of age and gender on the occurrence of bone changes (p ≤ 0.05). Bone changes were present in 227 (71%) patients. Age group and gender showed a statistically significant association with presence of bone changes (p ≤ 0.05). There was no significant difference between the right and left sides (p = 0.556) and in condylar mobility (p = 0.925) with regard to the presence of degenerative bone changes.
There is a high prevalence of degenerative bone alteration in TMJs, which is more frequent in women and mostly located in the condyle. The prevalence of degenerative bone changes increases with age. There is no correlation between condylar mobility and the presence of degenerative bony changes in TMJs.
Construction and demolition waste (CDW) destined for recycling companies has great potential for use in civil construction, since it gives rise to recycled aggregates of different particle sizes that ...can be used in concrete. However, there is a lack of studies on the durability of concrete produced with recycled aggregates from CDW. This study analyzed the influence of incorporating recycled aggregates from CDW, sand, and gravel on the durability parameters of SCC mixtures, with and without the addition of metakaolin (MK), when subjected to two exposure conditions: outdoors and in cycles of attack by chloride ions. Five mixtures were produced: reference SCC, with natural sand and gravel; SCC with recycled sand and gravel; SCC with recycled sand and gravel and the addition of 10% MK; SAC with recycled sand, natural gravel, and the addition of 10% MK; and SCC with natural sand, recycled gravel and the addition of 10% MK. The water/binder ratio was kept constant for all mixtures and the additive dosage was adjusted according to the variation in the use of aggregates. The mechanical and durability properties were assessed using axial compressive strength, ultrasonic pulse velocity, chloride penetration, chloride ion diffusion, and electrical resistivity tests. The results showed the feasibility of using recycled aggregates from CDW in SCC. The addition of MK significantly improved the performance of SCC using these aggregates. The mixtures with added MK showed a low risk of corrosion and high resistance to chloride ion penetration, and, under highly aggressive attack conditions, it was observed that the chloride ions did not exceed the minimum cover thickness recommended for reinforced concrete structures. The addition of MK to the mix with recycled aggregates caused an 84.6% reduction in the Cl− diffusion coefficient, there was also a 40.3% reduction in Cl− penetration and an increase of up to 156.14% in electrical resistivity compared to the mix with recycled aggregates without the addition of MK. The SCC mix with recycled sand and metakaolin stood out positively compared to the others, achieving an axial compressive strength similar to the reference mix (55.10 MPa). We, therefore, conclude that it is possible to produce such a mix with acceptable performance and ensure good behavior under aggressive environmental conditions.
Degradation and habitat loss of natural grasslands in Southern Brazil has a negative impact on native organisms, potentially including the composition of anuran helminth communities. Here, we ...characterized the richness, abundance, taxonomic composition, prevalence and intensity of helminth infection in four anuran species. Host anurans were collected in 34 ponds (19 in native grasslands with livestock and 15 in agricultural cultivation) from the highland grasslands in the Brazilian states of Santa Catarina and Paraná. Our results showed a significant difference between native grasslands with livestock and agricultural cultivation regarding the structure of helminth communities for the hosts Aplastodiscus perviridis and Pseudis cardosoi. We also found a greater prevalence and intensity of infection in anurans in areas of agricultural cultivation than in native grasslands with livestock. We found that the environmental descriptors (local and landscape) seem to explain most of the differences in anuran parasitism recorded between native grasslands with livestock and agricultural areas. Thus, we emphasized that the loss of grassy habitat due to conversion to agricultural cultivation can alter helminth communities in anurans, with further work needed to understand the mechanisms involved.
Caffeine (CAF) is an ergogenic aid used to improve exercise performance. Independent studies have suggested that caffeine may have the ability to increase corticospinal excitability, thereby ...decreasing the motor cortex activation required to generate a similar motor output. However, CAF has also been suggested to induce a prefrontal cortex (PFC) deoxygenation. Others have suggested that placebo (PLA) may trigger comparable effects to CAF, as independent studies found PLA effects on motor performance, corticospinal excitability, and PFC oxygenation. Thus, we investigated if CAF and CAF-perceived PLA may improve motor performance, despite the likely unchanged MC activation and greater PFC deoxygenation. Nine participants (26.4 ± 4.8 years old, VO
of 42.2 ± 4.6 mL kg
min
) performed three maximal incremental tests (MITs) in control (no supplementation) and ∼60 min after CAF and PLA ingestion. PFC oxygenation (near-infrared spectroscopy at Fp1 position), MC activation (EEG at Cz position) and vastus lateralis and rectus femoris muscle activity (EMG) were measured throughout the tests. Compared to control, CAF and PLA increased rectus femoris muscle EMG (
= 0.030;
= 2.88;
= 0.84) at 100% of the MIT, and enhanced the peak power output (
= 0.006;
= 12.97;
= 1.8) and time to exhaustion (
= 0.007;
= 12.97;
= 1.8). In contrast, CAF and PLA did not change MC activation, but increased the PFC deoxygenation as indicated by the lower O
Hb (
= 0.001;
= 4.68;
= 1.08) and THb concentrations (
= 0.01;
= 1.96;
= 0.7) at 80 and 100% the MIT duration. These results showed that CAF and CAF-perceived PLA had the ability to improve motor performance, despite unchanged MC activation and greater PFC deoxygenation. The effectiveness of CAF as ergogenic aid to improve MIT performance was challenged.
The present work focuses on assessing the viability of applying blasted copper slag, produced during abrasive blasting, as fine aggregate for Portland cement concrete manufacturing, resulting in an ...alternative and safe disposal method. Leaching assays showed no toxicity for this material. Concrete mixtures were produced, with high aggregate replacement ratios, varying from 0% to 100%. Axial compressive strength, diametrical compressive strength, elastic modulus, physical indexes and durability were evaluated. Assays showed a significant improvement in workability, with the increase in substitution of fine aggregate. With 80% of replacement, the concrete presented lower levels of water absorption capacity. Axial compressive strength and diametrical compressive strength decreased, with the increase of residue replacement content. The greatest reductions of compressive strength were found when the replacement was over 40%. For tensile strength by diametrical compression, the greatest reduction occurred for the concrete with 80% of replacement. After the accelerated aging, results of mechanic properties showed a small reduction of the concrete with blasted copper slag performance, when compared with the reference mixture. Results indicated that the blasted copper slag is a technically viable material for application as fine aggregate for concrete mixtures.
•Abrasive blasting generates large amounts of waste with unsafe disposal.•Blasted copper slag, as aggregate for concrete, provides safe disposal.•Blasted copper slag improved workability and reduced water absorption of concrete.•The mechanical behavior of concrete decreased as residue content increased.
Candida albicans is the most important fungal pathogen that causes infections in humans. Biofilms are hard-to-treat structures due to their high antifungal resistance. Saliva is a fluid that contains ...antimicrobial substances acting as the first-line of defense against pathogens, and its immune components may be potential tools for the discovery of new treatments against candidiasis. To evaluate the activity of histatin 5 and human lactoferrin against biofilm formation. A fluconazole-resistant Candida albicans clinical isolate was used as the model microorganism. Morphogenesis was evaluated by differential counting. Biofilm quantification was performed by XTT reduction assay. Thickness and topography of biofilms were assessed through confocal laser scanning microscopy (CLSM). Histatin 5 inhibited yeast-to-hyphae transition in a dose-dependent manner, while the effect of human lactoferrin on this process was inversely proportional to its concentration. Both compounds were able to significantly inhibit biofilm metabolic activity. Histatin 5 reduced biofilm thickness. Histatin 5 and human lactoferrin exhibited in vitro cytotoxicity against a fluconazole-resistant Candida albicans biofilm, which points to the potential application of these compounds in the treatment of biofilms formed by this fungus, especially in resistant infections.
Antimicrobial and antioxidant packaging play an important role in the food industry by ensuring food quality and prolonging the product's shelf life. Therefore, this scientific survey covers the ...technological domain in the active food packaging development processes and types of packaging.
This paper aims to provide a review of patents and scientific publications on active packaging with antimicrobial and antioxidant properties in order to show technological advances in this field of knowledge and its applicability in the food industry.
The patent review indicates an increase in the number of documents deposited in recent decades regarding various types of packaging formulations, particularly active packaging to preserve foods and their shelf life. In the last few decades, the scientific publication also includes several studies concerning the development of active food packaging using natural products with antimicrobial and antioxidant proprieties. Overall, the results show the advantages of incorporating natural products into polymer matrices to develop industrial packaging, providing a safe and high-quality food product to the consumer. On the other hand, the review also highlighted lack of cooperation between inventors and companies of active packaging development.
Further study in this regard would help provide data form research and patents on the active food-packaging field as well as economic issues, indicating the global development scenario of this innovative area.
Parasite infections may contingency different aspects of the hosts’ lives, and are usually expected to directly or indirectly compromise host reproduction. However, although amphibians have ...historically been study models in parasite ecology, the effects of parasitism on amphibians’ reproduction remain unknown. Thus, we investigated how the parasite load varies as a function of climatic seasonality (rainy and dry season) and intrinsic host characteristics (size and sex), as well as the relationship between parasite load and reproductive investment in males and females of a small frog (Pseudopaludicola pocoto Magalhães, Loebmann, Kokubum, Haddad & Garda, 2014) in the Brazilian semiarid region. The parasitological parameters of the studied population were not influenced by the season of the year or by the hosts’ body size, but females of P. pocoto had a higher prevalence and intensity of infection than males. The number of oocytes and the volume of the testes were not related to the parasite load, revealing that the parasitism did not negatively impact the gonadal investment in P. pocoto. Our findings suggest that short-lived species, such as the tiny Pseudopaludicola species, have a high reproductive investment independent of their parasitic interactions. In addition, this should be true mainly in those species that live in seasonally dry environments, such as P. pocoto, in which reproduction is even more constrained by the shortened and unpredictable rainy period.
RESUMO. Assembleia de helmintos em uma pequena rã no semiárido brasileiro: relação parasito-hospedeiro-ambiente. Como infecções parasitárias podem contigenciar diversos aspectos da vida dos hospedeiros, de modo geral, espera-se que o parasitismo comprometa direta ou indiretamente a reprodução dos hospedeiros. Contudo, apesar dos anfíbios historicamente terem sido modelos de estudos em ecologia parasitária, os efeitos do parasitismo na reprodução de anfíbios permanecem incompreendidos. Neste trabalho investigamos como a carga parasitária varia em função da sazonalidade climática (período chuvoso e seco) e de características intrínsecas do hospedeiros (tamanho e sexo), bem como a relação entre a intensidade de infecção e o investimento reprodutivo em machos e fêmeas de uma pequena rã (Pseudopaludicola pocoto Magalhães, Loebmann, Kokubum, Haddad & Garda, 2014) no semiárido brasileiro. Os parâmetros parasitológicos da população estudada não foram influenciados pela estação do ano nem pelo tamanho corpóreo dos hospedeiros, mas as fêmeas de P. pocoto apresentaram maior prevalência e intensidade de infecção que os machos. A carga parasitária não foi relacionada com o número de ovócitos nem com o volume dos testículos, revelando que o parasitismo não impactou negativamente o investimento gonadal em P. pocoto. Nossos achados sugerem que espécies com baixa longevidade, como as diminutas espécies de Pseudopaludicola, apresentam um alto investimento reprodutivo independente de suas interações parasitárias. Complementarmente, isto deve ocorrer sobretudo naquelas espécies que vivem em ambientes sazonalmente secos, como P. pocoto, nos quais a reprodução é ainda mais contigenciada pela brevidade e imprevisibilidade do período chuvoso.
ABSTRACT Snow Island is part of the South Shetland Archipelago in Antarctica. Most of its surface is permanently covered by snow, yet it has an important paleobotanical site. There are no protected ...areas on the island and no recent data regarding its vegetation. This study aimed to collect and identify fresh samples of bryophytes from President Head Peninsula of Snow Island. Samples were collected during the summers of 2015 and 2018. Among the 24 bryophyte species identified in this work, 19 are new occurrences for Snow Island, bringing the total known for the island to 29 species. The most diverse family is Pottiaceae, with four species of two genera, followed by Bryaceae and Polytrichaceae, with three species each. The results show that the diversity of mosses on Snow Island is greater than previously reported. We here demonstrated the region's importance and the 190 % increase in Snow Island species number. This study also updated the Antarctic distribution of some species.
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