Enhancing nonclassical correlations for light scattered by an ensemble of cold two-level atoms.

We report the enhancement of quantum correlations for biphotons generated via spontaneous four-wave mixing in an ensemble of cold two-level atoms. This enhancement is based on the filtering of the Rayleigh linear component of the spectrum of the two emitted photons, favoring the quantum-correlated sidebands reaching the detectors. We provide direct measurements of the unfiltered spectrum presenting its usual triplet structure, with Rayleigh central components accompanied by two peaks symmetrically located at the detuning of the excitation laser with respect to the atomic resonance. The filtering of the central component results in a violation of the Cauchy-Schwarz inequality to (4.8±1.0)≰1 for a detuning of 60 times the atomic linewidth, representing an enhancement by a factor of four compared with the unfiltered quantum correlations observed at the same conditions.

Observation of Nonclassical Correlations in Biphotons Generated from an Ensemble of Pure Two-Level Atoms.

We report the experimental verification of nonclassical correlations for an unfiltered spontaneous four-wave mixing process in an ensemble of cold two-level atoms, confirming theoretical predictions by Du et al. in 2007 for the violation of a Cauchy-Schwarz inequality in the system, and obtaining R=(1.98±0.03)≰1. Quantum correlations are observed in a nanoseconds timescale in the interference between the central exciting frequency and sidebands dislocated by the detuning to the atomic resonance. They prevail over the noise background coming from Rayleigh scattering from the same optical transition. These correlations are fragile with respect to processes that disturb the phase of the atomic excitation, but are robust to variations in number of atoms and to increasing light intensities.

Community-based assessment of marine resources contamination after a large-scale oil spill.

As of August 2019, several oil slicks reached the Brazilian coast, compromising local ecosystems and the economy of coastal communities. In this context, this study aimed to assess seafood quality at the Canavieiras Extractive Reserve (RESEX), located in the state of Bahia, Northeastern Brazil, by determining polycyclic aromatic hydrocarbons (PAHs) concentrations in local biota following the oil spill. It was designed and carried out in a participatory manner, involving RESEX fishers, shellfish and crab gatherers and managers, as well as university researchers. A total of 72 biota samples were analyzed, and the sum of the 16 priority USEPA PAHs ranged from less than the limit of detection to 30.81 ng g-1 (w.w.). When also considering alkylated compounds, concentrations ranged from 3.53 to 360.75 ng g-1 (w.w.). No sample contained PAHs concentrations suggestive of human consumption risks. No difference in PAHs concentrations between the six studied areas and regarding different biota feeding habits were observed. Higher PAHs concentrations were generally noted in molluscs, as these organisms do not have enzyme systems capable of metabolizing these compounds. This initiative demonstrated the feasibility of participatory construction resulting in a study concerning valued species to local communities, ensuring a contribution to local fishing and marketing activities.

Initial steps on mapping differentially expressed proteins in bovine preantral follicles and ovarian tissue: An approach using single-follicle MALDI-MS and mass spectrometry imaging (MSI) analysis.

The molecular mechanisms regulating follicular development and ensuring primordial follicle activation remain undefined. To help elucidate these mechanisms, this proteomic study of bovine ovarian tissue identified the differential molecular profiles of preantral follicles together with the spatial distribution of the most abundant molecular components in the tissue. Isolated primordial, primary and secondary follicles were individually placed on a MALDI target plate for mass spectral acquisitions, with detection of different m/z ranges. Ovarian tissue was sectioned and analysed in the m/z 400-2,000 range. Results of the first analysis indicated a similarity pattern in the molecular protein profile among different follicular classes in the m/z ranges of 100-1000 and 25,000-200,000, but in the m/z ranges of 800-4000, 4000-20,000 and 15,000-70,000, primary and secondary follicles shared similar clustering profiles which were different from primordial follicles (p < .05). In the second analysis, it was possible to correlate some intense molecular components in the tissue from global mass spectrum with the ions detected in the first analysis. Molecular components at m/z 11,325 (±230) were also detected in primary and secondary follicles in the experiment with isolated follicles, in addition to ions at m/z 4,029 (±120), 13,799 (±70), 5,547 (±9), 15,313 (±200), 7,018 (±40) and 7,663 (±90) which were also intensely detected in primary and secondary follicles. The present proteomic approaches evaluated different mass ranges of preantral follicles in bovine ovarian tissue and also indicated the spatial distribution of the most abundant molecular components. This study hopes to pave the way for future research identifying and characterizing specific proteins involved in follicle activation in bovine follicles, in order to better understand folliculogenesis and potentially improve mammalian follicle culture systems.

Pilocarpine-Induced Status Epilepticus Increases the Sensitivity of P2X7 and P2Y1 Receptors to Nucleotides at Neural Progenitor Cells of the Juvenile Rodent Hippocampus.

Patch-clamp recordings indicated the presence of P2X7 receptors at neural progenitor cells (NPCs) in the subgranular zone of the dentate gyrus in hippocampal brain slices prepared from transgenic nestin reporter mice. The activation of these receptors caused inward current near the resting membrane potential of the NPCs, while P2Y1 receptor activation initiated outward current near the reversal potential of the P2X7 receptor current. Both receptors were identified by biophysical/pharmacological methods. When the brain slices were prepared from mice which underwent a pilocarpine-induced status epilepticus or when brain slices were incubated in pilocarpine-containing external medium, the sensitivity of P2X7 and P2Y1 receptors was invariably increased. Confocal microscopy confirmed the localization of P2X7 and P2Y1 receptor-immunopositivity at nestin-positive NPCs. A one-time status epilepticus in rats caused after a latency of about 5 days recurrent epileptic fits. The blockade of central P2X7 receptors increased the number of seizures and their severity. It is hypothesized that P2Y1 receptors after a status epilepticus may increase the ATP-induced proliferation/ectopic migration of NPCs; the P2X7 receptor-mediated necrosis/apoptosis might counteract these effects, which would otherwise lead to a chronic manifestation of recurrent epileptic fits.

Silencing of P2X7R by RNA interference in the hippocampus can attenuate morphological and behavioral impact of pilocarpine-induced epilepsy.

Cell signaling mediated by P2X7 receptors (P2X7R) has been suggested to be involved in epileptogenesis, via modulation of intracellular calcium levels, excitotoxicity, activation of inflammatory cascades, and cell death, among other mechanisms. These processes have been described to be involved in pilocarpine-induced status epilepticus (SE) and contribute to hyperexcitability, resulting in spontaneous and recurrent seizures. Here, we aimed to investigate the role of P2X7R in epileptogenesis in vivo using RNA interference (RNAi) to inhibit the expression of this receptor. Small interfering RNA (siRNA) targeting P2X7R mRNA was injected into the lateral ventricles (icv) 6 h after SE. Four groups were studied: Saline-Vehicle, Saline-siRNA, Pilo-Vehicle, and Pilo-siRNA. P2X7R was quantified by western blotting and neuronal death assessed by Fluoro-Jade B histochemistry. The hippocampal volume (edema) was determined 48 h following RNAi. Behavioral parameters as latency to the appearance of spontaneous seizures and the number of seizures were determined until 60 days after the SE onset. The Saline-siRNA and Pilo-siRNA groups showed a 43 and 37% reduction, respectively, in P2X7R protein levels compared to respective vehicle groups. Neuroprotection was observed in CA1 and CA3 of the Pilo-siRNA group compared to Pilo-Vehicle. P2X7R silencing in pilocarpine group reversed the increase in the edema detected in the hilus, suprapyramidal dentate gyrus, CA1, and CA3; reduced mortality rate following SE; increased the time to onset of spontaneous seizure; and reduced the number of seizures, when compared to the Pilo-Vehicle group. Therefore, our data highlights the potential of P2X7R as a therapeutic target for the adjunct treatment of epilepsy.

Superradiance in a Large and Dilute Cloud of Cold Atoms in the Linear-Optics Regime.

Superradiance has been extensively studied in the 1970s and 1980s in the regime of superfluorescence, where a large number of atoms are initially excited. Cooperative scattering in the linear-optics regime, or "single-photon superradiance," has been investigated much more recently, and superradiant decay has also been predicted, even for a spherical sample of large extent and low density, where the distance between atoms is much larger than the wavelength. Here, we demonstrate this effect experimentally by directly measuring the decay rate of the off-axis fluorescence of a large and dilute cloud of cold rubidium atoms after the sudden switch off of a low-intensity laser driving the atomic transition. We show that, at large detuning, the decay rate increases with the on-resonance optical depth. In contrast to forward scattering, the superradiant decay of off-axis fluorescence is suppressed near resonance due to attenuation and multiple-scattering effects.

Subradiance in a Large Cloud of Cold Atoms.

Since Dicke's seminal paper on coherence in spontaneous radiation by atomic ensembles, superradiance has been extensively studied. Subradiance, on the contrary, has remained elusive, mainly because subradiant states are weakly coupled to the environment and are very sensitive to nonradiative decoherence processes. Here, we report the experimental observation of subradiance in an extended and dilute cold-atom sample containing a large number of particles. We use a far detuned laser to avoid multiple scattering and observe the temporal decay after a sudden switch-off of the laser beam. After the fast decay of most of the fluorescence, we detect a very slow decay, with time constants as long as 100 times the natural lifetime of the excited state of individual atoms. This subradiant time constant scales linearly with the cooperativity parameter, corresponding to the on-resonance optical depth of the sample, and is independent of the laser detuning, as expected from a coupled-dipole model.

Trade-offs in the externalities of pig production are not inevitable.

Farming externalities are believed to co-vary negatively, yet trade-offs have rarely been quantified systematically. Here we present data from UK and Brazilian pig production systems representative of most commercial systems across the world ranging from 'intensive' indoor systems through to extensive free range, Organic and woodland systems to explore co-variation among four major externality costs. We found that no specific farming type was consistently associated with good performance across all domains. Generally, systems with low land use have low greenhouse gas emissions but high antimicrobial use and poor animal welfare, and vice versa. Some individual systems performed well in all domains but were not exclusive to any particular type of farming system. Our findings suggest that trade-offs may be avoidable if mitigation focuses on lowering impacts within system types rather than simply changing types of farming.

[Assessment of the implementation of an care teleregulation project in a Brazilian capital city]. / Avaliação da implantação de um projeto de telerregulação assistencial em uma capital brasileira.

This study evaluates the degree of implementation (DI) of the Regulates+ Brazil project and analyzes to what extent the variations in implementation influence the results observed in access to specialized appointments in Recife, Pernambuco, Brazil. This is an evaluative research of implementation analysis. A logic model and an analysis and judgment matrix with indicators for evaluating the degree of implementation and the results of the Project were developed and submitted to expert consensus. The data collection was conducted via a semi-structured questionnaire applied to key informants and secondary data extracted from the official documents from Regulates+ Brazil and Brazilian National Regulation System (SISREG), referring to the period from May/2020 to May/2021, which were consolidated and compared with values defined in the matrix. The degree of implementation of the Regulates+ Brazil project in Recife was considered to be implemented (83.7%), as well as the Structure (81.7%) and Methods (84.6%) dimensions. However, most effect indicators underperformed, which, when confronted, were consistent with bottlenecks observed in some components and subcomponents of the Project, such as the performance of professionals in basic health units, which was indicated as incipient, especially regarding follow-up of returned requests. The results suggest that any intervention in Telehealth requires, for its proper implementation, the adequacy of teams and work processes, practices of Continuing Education, as well as a continuous evaluation process, to achieve the expected results, or else it will become another bureaucratization and barrier to access.

Os objetivos foram avaliar o grau de implantação do projeto Regula+ Brasil e analisar em que medida as variações da implantação influenciam nos resultados observados no acesso a consultas especializadas em Recife, Pernambuco, Brasil. Trata-se de uma pesquisa avaliativa de análise de implantação. Foram elaborados o modelo lógico e a matriz de análise e julgamento com os indicadores para avaliação do grau de implantação e de resultado do projeto, os quais foram submetidos ao consenso de especialistas. A coleta de dados se deu por meio de questionário semiestruturado, aplicado com informantes-chave, e dados secundários extraídos dos documentos oficiais do projeto e do Sistema Nacional de Regulação (SISREG), referentes ao período de maio de 2020 a maio de 2021, os quais foram consolidados e comparados com valores definidos na matriz. O grau de implantação do projeto Regula+ Brasil em Recife foi considerado implantado (83,7%), bem como as dimensões Estrutura (81,7%) e Processo (84,6%). Entretanto, a maioria dos seus indicadores de efeito obtiveram desempenho insatisfatório. Quando confrontados, guardaram coerência com gargalos observados em alguns componentes e subcomponentes do projeto, como a atuação dos profissionais das unidades básicas de saúde (UBS), apontada como incipiente, principalmente no que diz respeito ao acompanhamento das solicitações devolvidas. Os resultados sugerem que qualquer intervenção em telessaúde requer, para sua devida implantação e para o alcance dos resultados esperados, adequação das equipes e dos processos de trabalho, práticas de educação permanente e processo contínuo de avaliação, ou então se configurará em nova burocratização e barreira de acesso.

El objetivo fue evaluar el grado de implementación del proyecto Regula+ Brasil y analizar en qué medida las variaciones de la implementación influyen en los resultados observados en el acceso a consultas especializadas en Recife, Pernambuco, Brasil. Se trata de una investigación evaluativa del análisis de la implantación. Se elaboró un modelo lógico y una matriz de análisis y juicio con los indicadores para la evaluación de la grado de implementación y el resultado del Proyecto, los cuales se sometieron al consenso de especialistas. La recopilación de datos se realizó por medio de un cuestionario semiestructurado aplicado con informantes clave y datos secundarios extraídos de documentos oficiales del Regula+ Brasil y del Sistema Nacional de Regulación (SISREG), relativos al período de mayo de 2020 a mayo de 2021, los cuales fueron consolidados y comparados con valores definidos en el matriz. El grado de implementación del proyecto Regula+ Brasil en Recife fue considerado implementado (83,7%), así como las dimensiones Estructura (81,7%) y Proceso (84,6%). Sin embargo, la mayoría de sus indicadores de efecto obtuvieron un desempeño insatisfactorio, los cuales, al ser confrontados, fueron coherentes con los cuellos de botella observados en algunos componentes y subcomponentes del Proyecto, como el desempeño de los profesionales de las unidades básicas de salud, señalada como incipiente, sobre todo en lo que respecta al seguimiento de las solicitudes devueltas. Los resultados sugieren que toda intervención en Telesalud requiere, para su debida implantación, la adecuación de los equipos y de los procesos de trabajo, prácticas de Educación Permanente, así como un proceso continuo de evaluación, para alcanzar los resultados esperados, o entonces se configurará en una nueva burocratización y barrera de acceso.

Aliphatic and polycyclic aromatic hydrocarbons in surface sediments as a tool for the assessment of the contamination status of mangrove forests in Rio de Janeiro (Brazil).

The distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from mangrove forests of the Rio de Janeiro State was investigated. Ten sampling stations were selected in the mangroves of Sepetiba Bay and the Jacarepaguá Lagoon Complex (JLC), which are areas affected by multiple human activities. The total aliphatic hydrocarbons concentrations showed marked variation between samples (27-407 µg g-1), mostly related to the total organic carbon contents. The total PAHs concentration ranged between 38 and 792 ng g-1. Diagnostic indices and statistical analysis showed that the mangrove forests can be divided into three groups: the western portion of Sepetiba Bay with the lowest level of contamination; the inner portion of the bay with the most intense presence of local sources of contamination, especially of pyrolytic character; and the JLC with a greater accumulation of hydrocarbons, mainly derived from petroleum combustion, resultant from the intense urbanization.

Organosolv pretreatment for biorefineries: Current status, perspectives, and challenges.

Biorefineries integrate processes for the sustainable conversion of biomass into chemicals, materials, and bioenergy so that resources are optimized and effluents are minimized. Despite the vast potential of lignocellulosic biorefineries, their success depends heavily on effective, economically viable, and sustainable biomass fractionation. Although efficient, organosolv pretreatment still faces challenges that must be overcome for its widespread utilization, mainly related to solvent type and recycling, robustness regarding biomass type and integration of hemicellulose recovery and use. This review shows the recent advances and state-of-the-art of organosolv pretreatment, discussing the advances, such as the use of biobased solvents, whilst also shedding light on the perspectives of using the streams - cellulose, hemicellulose, and lignin - to produce biofuels and products of high added value. In addition, it presents an overview of the existing industrial implementations of organosolv processes and, lastly, shows the main scientific and industrial challenges and opportunities for this process.

Posterior segment findings by spectral-domain optical coherence tomography and clinical associations in active toxoplasmic retinochoroiditis.

Toxoplasmic retinochoroiditis is a common, potentially blinding parasitic infection. We sought to define the spectrum and frequency of signs of active toxoplasmic retinochoroiditis by spectral domain optical coherence tomography (SD-OCT), and to identify clinical associations. Ninety eyes of 90 individuals presenting consecutively to a tertiary referral uveitis service with active toxoplasmic retinochoroiditis and gradable SD-OCT scans were evaluated prospectively. SD-OCT features were collated, and associations with lesion location, primary versus recurrent episode, serological status, human immunodeficiency virus infection and best-corrected Snellen visual acuity were explored. Active toxoplasmic retinochoroiditis presented with thickened (65%) and hyperreflective (61%) retina, choroidal thickening (55%) and hyporeflectivity (61%), hyperreflective vitreous dots (80%) and deposits (36%), and posterior hyaloid thickening (35%) on SD-OCT. Most signs occurred with similar frequency across clinical groups. Retinal hyporeflectivity (17%) was significantly associated with a visual acuity of 20/200 or worse at resolution. Our observations demonstrate that active toxoplasmic retinochoroiditis has diverse SD-OCT signs and that none are universally present. Retinal hyporeflectivity-suggesting liquefactive necrosis-predicts poor visual outcome.

Vaginal Microbiota Diversity in Response to Lipopolysaccharide in Gilts Housed Under Three Housing Systems.

The United Kingdom and European Union have banned crates for pregnant sows. However, animals are kept in a restrictive environment for up to four weeks after mating, leading to stress and different responses of the animals' immune system. Here, we used vaginal flushing of gilts to investigate whether housing systems or an experimental inflammatory challenge with lipopolysaccharide (LPS) can modify the gilt vaginal microbiome. Alpha-diversity indices showed differences in the microbiota of gilts housed under different systems (q = 0.04). Shannon alpha-diversity richness was higher in gilts group-housed in pens than in gilts housed in crates (q = 0.035), but not higher than in other groups. The relative abundance of the operational taxonomic unit (OTU) (q < 0.05) revealed specific differences in housing systems before a LPS or saline (SAL control) challenge. We found different abundances in taxa of Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, and Proteobacteria in gilts housed in the different systems before challenge. After the LPS challenge, significant differences were detected in the relative abundance of OTUs (q < 0.05) for the LPS-challenged group compared with SAL animals for each housing system. The phylum Staphylococcus showed higher abundance among the LPS-challenged gilts than in SAL-challenged animals. Furthermore, Enterobacter was more abundant in the LPS-challenged gilts housed in crates than in SAL-challenged gilts housed in crates. Streptococcus suis, Conchiformibius, Globicatella and Actinobacillus were more abundant in LPS-challenged gilts in indoor group housing than in SAL gilts in the same housing system. Gilts kept outdoors did not show changes in vaginal microbiota after an LPS challenge. Gilts housed in crates showed clinical signs of urogenital infection, whereas gilts housed outdoors and in indoor group housing did not. The relationship between environment, immune response, and microbiota suggested that animals in a poor environments experience difficulties responding to a challenge and their vaginal microbiota is altered as a consequence, with decreased richness of normal vaginal microbiota, and increased opportunistic bacteria. Welfare indicators measured by gilts' responses to housing systems however, do not fully explain mechanisms associated with the unique signature in vaginal microbiota encountered in the different housing systems.

Case report: An innovative non-invasive technique to manage shell injuries in C. carbonarius.

Shell fractures are one of the most traumatic and recurrent injuries observed in chelonians during clinical practice. The most common causes of fractures are falling, being run over by automobiles, being burned, and wild animal bites. Epoxy, acrylic resin, polyester, fiber-grass blanket, and screw fixation are among the current techniques used to treat fractures. Regarding the difficulty of fracture repair in the carapace, this case report aimed to report a procedure that is effective, less time-consuming, accessible, affordable, and safe for shell fractures in C. carbonarius. During the physical examination, the animal showed two fractures, in the dorsal region of the carapace and right lateral side of the bridge, with subcutaneous tissue exposure and loss of a small piece of dorsocranial carapace. To treat these injuries, the animal was submitted to a resin application. The procedure consists of using ethyl-cyanoacrylate associated with sodium bicarbonate, which produces a more resistant resin that is bactericidal, non-toxic, and easy to apply in a low surgery time compared to the common methods used to fix shell fractures. The resin application was successfully done, and the animal was under care for a month after the fracture reduction. It was observed that the treatment was effective, presenting reduction of the fracture. A month after the procedure, the animal showed no intercurrence. Three years after the procedure, the animal still presents part of the material still fixed to the shell, normal growth, without interference in locomotor capacity. This resin proved to be an innovative and promising alternative way to treat fractures, suggesting the development of new non-invasive approaches for several tissues and different animal species.

Insights into the influence of canine breed on proteomics of the spermatozoa and seminal plasma.

This study aimed to characterize the proteome of spermatozoa and seminal plasma of 4 purebred dogs (Golden Retriever, Great Dane, Bernese Mountain Dog, and Maremmano-Abruzzese Sheepdog). The ejaculate of 13 dogs was collected, and sperm characteristics were subjectively evaluated. Seminal plasma and sperm cells were separated and prepared individually for mass spectrometry. Data were evaluated by univariate and multivariate statistical analysis. A total of 162 proteins were identified, 47 in spermatozoa, 109 in seminal plasma, and 6 in both samples. Serum albumin in spermatozoa and tubulin alpha-3E chain, acrosin binding protein, and tubulin alpha-3 chain in plasma seminal were statistically relevant. Serum albumin and acrosin binding protein improve the sperm capacitation, acrosome reaction, and seminal quality. The tubulin family proteins are related to structural cell organization and flagella movement, and their presence in seminal plasma may be related to sample handling. According to cluster formation, a high association was observed among Bernese Mountain Dog and Great Dane, Golden Retriever, and Maremmano-Abruzzese Sheepdog for sperm proteins. For seminal plasma proteins, Bernese Mountain Dog, Great Dane, and Maremmano-Abruzzese Sheepdog were related. Further studies on breed-specific proteins in the semen of purebred dogs need to be performed to clarify its fertility roles. SIGNIFICANCE: For the first time spermatozoa proteins of dogs are described. The comparison of spermatozoa and seminal plasma proteins of four purebred dogs were performed. These results supporting that differences in semen protein profile of different canine breeds exist, which can improve the biotechnologies of reproduction in this species.

Recellularized rat testis scaffolds with embryoid bodies cells: a promising approach for tissue engineering.

Tissue engineering is gaining use to investigate the application of its techniques for infertility treatment. The use of pluripotent embryonic cells for in vitro production of viable spermatozoa in testicular scaffolds is a promising strategy that could solve male infertility. Due to cell-extracellular matrix (ECM) interactions, here we aim to investigate the differentiation of embryoid bodies (EBs) in cultured into decellularized rat testis scaffolds. Decellularized testis (P = 0.019) with a low concentration of gDNA (30.58 mg/ng tissue) was obtained by sodium dodecyl sulfate perfusion. The structural proteins (collagens type I and III) and the adhesive glycoproteins of ECM (laminin and fibronectin) were preserved according to histological and scanning electron microscopy (SEM) analyses. Then, decellularized rat testis were cultured for 7 days with EB, and EB mixed with retinoic acid (RA) in non-adherent plates. By SEM, we observe that embryonic stem cells adhered in the decellularized testis ECM. By immunofluorescence, we verified the positive expression of HSD17B3, GDNF, ACRV-1, and TRIM-36, indicating their differentiation using RA in vitro, reinforcing the possibility of EB in male germ cell differentiation. Finally, recellularized testis ECM may be a promising tool for future new approaches for testicular cell differentiation applied to assisted reproduction techniques and infertility treatment.Abbreviations: ACRV-1: Acrosomal vesicle protein 1; ATB: Penicillin-streptomycin; DAPI: 4,6-Diamidino-2-phenylindole; EB: Embryoid bodies; ECM: Extracellular matrix; ESCs: Pluripotent embryonic stem cells; GAGs: Glycosaminoglycans; gDNA: Genomic DNA; GDNF: Glial cell line-derived neurotrophic factor; H&E: Hematoxylin and eosin; HSD17B3: 17-beta-Hydroxysteroid dehydrogenase type 3; PBS: Phosphate-buffered saline; PGCLCs: Primordial germ-cell-like cells; RA: Retinoic acid; SDS: Sodium dodecyl sulfate; SEM: Scanning electron microscopy; SSCs: Spermatogonial stem cells; TRIM-36: Tripartite Motif Containing 36.

Seminal Plasma Does Not Influence Canine Semen Stored at 5°C for Long-Term Conservation.

Seminal plasma has several components that protect the sperm cells and assist in the fertilization process. In contrast, the exact role carried out by seminal plasma during the cooling of canine semen remains controversial. Moreover, concerning the long estrus period, the possibility to store chilled semen at 5°C for more than 72 hours and maintain good sperm quality for additional inseminations could increase fertilization rates. Thus, this study aimed to evaluate the seminal plasma influence on quality and oxidative stress of the extended canine semen stored at 5°C for 7 days. Three ejaculate pools from eight healthy dogs were collected by digital manipulation of the penis. The sperm kinetics, sperm vitality (eosin/nigrosin stain), integrity of plasma and acrosomal membranes, morphology, superoxide and hydrogen peroxide production, mitochondrial potential, lipid peroxidation, and oxygen reactive species production (induced and spontaneous thiobarbituric acid [thiobarbituric acid reactive substances, TBARS] assay) were evaluated every 48 hours (M0, M48, M96, and M168) until 7 days (168 hours) in cooled extended (TRIS egg yolk) semen of dogs at 5°C with (+SP) or without (-SP) autologous seminal plasma. No statistical difference was found for sperm kinetics in cooled samples with +SP and -SP during the experimental time period, except for the progressive motility of +SP samples that was higher at M48 than M96 (p = 0.023). The seminal plasma did not influence any other evaluated sperm characteristics. Finally, our results demonstrated that the presence or lack of seminal plasma during cooling the semen of dogs does not influence sperm quality at 5°C. Moreover, the components of the semen extender may contribute to maintaining good sperm quality and low reactive oxygen species production during the long period of the dog's semen cooling, even after semen centrifugation.

Uterine Tissue Engineering: Where We Stand and the Challenges Ahead.

Tissue engineering is an innovative approach to develop allogeneic tissues and organs. The uterus is a very sensitive and complex organ, which requires refined techniques to properly regenerate and even, to rebuild itself. Many therapies were developed in 20th century to solve reproductive issues related to uterus failure and, more recently, tissue engineering techniques provided a significant evolution in this issue. Herein we aim to provide a broad overview and highlights of the general concepts involved in bioengineering to reconstruct the uterus and its tissues, focusing on strategies for tissue repair, production of uterine scaffolds, biomaterials and reproductive animal models, highlighting the most recent and effective tissue engineering protocols in literature and their application in regenerative medicine. In addition, we provide a discussion about what was achieved in uterine tissue engineering, the main limitations, the challenges to overcome, and future perspectives in this research field. Impact Statement This review presents the applications of tissue engineering in uterine reconstruction and in regenerative therapies of uterine wall injuries.

Lévy flights of photons with infinite mean free path.

Multiple scattering of light by resonant vapor is characterized by Lévy-type superdiffusion with a single-step size distribution p(x)∝1/x^{1+α}. We investigate Lévy flight of light in a hot rubidium vapor collisional-broadened by 50 torr of He gas. The frequent collisions produce Lorentzian absorptive and emissive profiles with α<1 and a corresponding divergent mean step size. We extract the Lévy parameter α≈0.5 in a multiple-scattering regime from radial profile of the transmission and from violation of the Ohm's law. The measured radial transmission profile and the total diffusive transmission curves are well reproduced by numerical simulations for Lorentzian line shapes.