Sub-acute exposure of male guppies (Poecilia reticulata) to environmentally relevant concentrations of PFOA and GenX induces significant changes in the testis transcriptome and reproductive traits.

Poly- and perfluoroalkyl substances (PFAS) are frequently detected in the environment and are linked to adverse reproductive health outcomes in humans. Although legacy PFAS have been phased out due to their toxicity, alternative PFAS are increasingly used despite the fact that information on their toxic effects on reproductive traits is particularly scarce. Here, we exposed male guppies (Poecilia reticulata) for a short period (21 days) to an environmentally realistic concentration (1 ppb) of PFOA, a legacy PFAS, and its replacement compound, GenX, to assess their impact on reproductive traits and gene expression. Exposure to PFAS did not impair survival but instead caused sublethal effects. Overall, PFAS exposure caused changes in male sexual behaviour and had detrimental effects on sperm motility. Sublethal variations were also seen at the transcriptional level, with the modulation of genes involved in immune regulation, spermatogenesis, and oxidative stress. We also observed bioaccumulation of PFAS, which was higher for PFOA than for GenX. Our results offer a comprehensive comparison of these two PFAS and shed light on the toxicity of a newly emerging alternative to legacy PFAS. It is therefore evident that even at low concentrations and with short exposure, PFAS can have subtle yet significant effects on behaviour, fertility, and immunity. These findings underscore the potential ramifications of pollution under natural conditions and their impact on fish populations.

Magnetoelectric nanoparticles shape modulates their electrical output.

Core-shell magnetoelectric nanoparticles (MENPs) have recently gained popularity thanks to their capability in inducing a local electric polarization upon an applied magnetic field and vice versa. This work estimates the magnetoelectrical behavior, in terms of magnetoelectric coupling coefficient (αME), via finite element analysis of MENPs with different shapes under either static (DC bias) and time-variant (AC bias) external magnetic fields. With this approach, the dependence of the magnetoelectrical performance on the MENPs geometrical features can be directly derived. Results show that MENPs with a more elongated morphology exhibits a superior αME if compared with spherical nanoparticles of similar volume, under both stimulation conditions analyzed. This response is due to the presence of a larger surface area at the interface between the magnetostrictive core and piezoelectric shell, and to the MENP geometrical orientation along the direction of the magnetic field. These findings pave a new way for the design of novel high-aspect ratio magnetic nanostructures with an improved magnetoelectric behaviour.

Liquid storage of Ostrich (Struthio camelus) semen at 5 °C through intermediate dilution.

Dilution rate, dilution temperature and storage time have been recognized as vital steps in the processing of semen for storage before artificial insemination. The objective of this study was to determine optimal dilution and dilution temperature with an ostrich-specific semen extender for chilled storage. Four preselected ostrich (Struthio camelus var. domesticus) males, known for their ease of collection and specific semen quality parameters, were collected using the "dummy" female method. Dilution of 384 semen samples, at rates of 1:1, 1:2, 1:4 and 1:8 semen/diluent ratio with a diluent set at 5, 21 and 38 °C was performed and stored for 48 h at 5 °C. In vitro sperm function tests were conducted to evaluate treated semen during different storage intervals of 1, 5, 24 and 48 h. Motility and kinematic parameters were measured by the Sperm Class Analyzer®, the percentage live sperm measured by fluorescence SYBR14®/PI (LIVE/DEAD®), the percentage of sperm able to resist the hypo-osmotic swelling (HOS) stress test and sperm morphology determined by Nigrosin-Eosin staining. Progressive motility (PMOT), motility (MOT), sperm kinematics, LIVE and HOS were best (P < 0.05) maintained at a higher dilution of 1:4-1:8. The beneficial effect (P < 0.05) of a higher dilution temperature (21 °C) was prominent in terms of PMOT at a higher dilution. Storage of chilled semen at 5 °C requires dilution, at interpolated rates of 1:6-1:7, together with an extender temperature of 21 °C, to maintain optimal sperm function with minimal loss over a 48 h storage period.

Computational Evaluation of Combined Cerebellar and Frontal Transcranial Direct Current Stimulation for Treatment-Resistant Depression.

This work aimed to estimate the distribution of the electric field generated by a combined cerebellar and frontal transcranial direct current stimulation (tDCS) for treatment-resistant depression using electromagnetics computational techniques applied to a realistic head human model. Results showed that the stronger electric fields occur mainly in the cerebellum and in DLPFC areas, where the two pairs of electrodes were applied. Furthermore, the study demonstrated that the simultaneous use of the two pairs of electrodes did not imply a lower effectiveness of the tDCS technique, in fact the electric field distributions in the primarily targets of the anatomical regions (i.e., cerebellum and DLPFC) were very similar to when the pairs of electrodes were applied separately.

Gold nanoparticles as enablers of cell membrane permeabilization by time-varying magnetic field: influence of distance and geometry.

This study is based on the quantification of the influence of the presence of gold nanoparticles (Au NPs), of their geometry and their distance from cell membrane during time-varying electromagnetic fields cell membrane permeabilization on the pores opening dynamics. Results showed that the combined use of Au NPs and time-varying magnetic field can improve significantly the permeabilization of cell membrane. The presence of Au NPs allowed to reach transmembrane potential values enabling the cell membrane permeabilization only when placed at very short distance, equal to 20 nm. Both geometry and variability of the positioning in proximity of the cell membrane showed a strong influence on the probability of enabling pores opening. Clinical Relevance- This study provides a better comprehension about the mechanisms, still not completely understood, underlying cell membrane permeabilization by combining Au NPs and time-varying magnetic fields.

Application of Stochastic Dosimetry for assessing the Human RFEMF Exposure in a 5G indoor Scenario.

In recent years the introduction of 5G networks is causing a drastically change of human exposure levels in the radio frequency range. The aim of this paper is on expanding the knowledge on this issue, assessing the exposure levels for a particular case of indoor 5G scenario, where the presence of an Access Point (AP) was simulated. Coupling the traditional deterministic computational method with an innovative stochastic approach, called Polynomial Chaos Kriging, allowed to evaluate the exposure variability of an user considering the 3D beamforming capability of the antenna. The exposure levels, expressed in terms of specific absorption rate (SAR) in specific tissues, showed low values compared to ICNIRP guidelines.

Contactless Cell Permeabilization by Time-Varying Magnetic fields: Modelling Transmembrane Potential and Mechanical Stress in in- vitro Experimental Set-Up.

The feasibility of using time-varying magnetic field as a contactless cells permeabilization method was demonstrated by experimental results, but the underlying mechanism is still poorly understood. In this study a numerical analysis of the transmembrane potential (TMP) at cell membranes during permeabilization by time-varying magnetic fields was proposed, and a first quantification of mechanical stress induced by the magnetic and electric fields and hypothesized to play an important role in the permeabilization mechanism was carried out. TMP values induced by typical in-vitro experimental conditions were far below the values needed for membrane permeabilization, with a strong dependence on distance of the cell from the coil. The preliminary assessment of the mechanical pressure and potential deformation of cells showed that stress values evaluated in conditions in which TMP values were too low to cause membrane permeabilization were comparable to those known to influence the pore opening mechanisms.Clinical Relevance- Results represent a significant step towards a better comprehension of the mechanism underlying cell membrane permeabilization by time-varying magnetic fields.

Cell transmembrane potential in contactless permeabilization by time-varying magnetic fields.

BACKGROUND: Although experimental results proved the feasibility of using time-varying magnetic field as a contactless cells permeabilization method, the underlying mechanism is still poorly understood. In this study a numerical analysis of the time-dependent transmembrane potential (TMP) at cell membranes during permeabilization by time-varying magnetic fields was proposed, and a first quantification of mechanical stress induced by the magnetic and electric fields, hypothesized to play an important role in the permeabilization mechanism, was carried out. METHODS: Starting from the simulation of real in vitro experimental conditions, the analysis was widened quantifying the influence of pulse frequency, cell dimension and distance of the cell from the magnetic field source. The mechanical pressure on cell membrane due to the interaction between free charges and induced electric field and due to the gradient of the magnetic field was quantified in all those conditions in which the TMP values were not high enough to cause membrane permeabilization. RESULTS: TMP values induced by typical in-vitro experimental conditions were far below the values needed for membrane permeabilization, with a strong dependence on pulse frequency and distance of the cell from the coil. CONCLUSION: The preliminary assessment of the mechanical pressure on cell membrane showed that stress values evaluated in conditions in which TMP values were too low to cause membrane permeabilization were comparable to those known to influence the pores opening mechanisms. Results represent a significant step towards a better comprehension of the mechanism underlying cell membrane permeabilization by time-varying magnetic fields.

Meat quality, skin damage and reproductive performance of ostriches exposed to extensive human presence and interactions at an early age.

The effect human presence and interactions performed after hatch to 3 months of age has on ostrich meat quality, skin damage and reproductive performance at a later age was investigated in 416-day-old ostrich chicks. The chicks were allocated to one of the three treatments, which varied with regard to exposure to human presence and care for 3 months post-hatch: HP1-extensive human presence with physical contact (touch, stroking), gentle human voice and visual contact; HP2-extensive human presence with gentle human voice and visual contact without physical contact; S-standard control treatment, where human presence and visual contact were limited to routine management, feed and water supply only. Carcass attributes (carcass weight, dressing percentage and drumstick weight), meat quality traits (pH, colour and tenderness) and skin traits (skin size, skin grading and number of lesions) were evaluated on twenty-four 1-year-old South African Black (SAB) ostriches. Reproductive performance (egg production, average egg weight, number of clutches, clutch size, chick production, average chick weight, fertility and hatchability percentage) were recorded for the first three breeding seasons of 23 SAB pair-bred females from this study. No differences in carcass attributes, meat quality, skin traits and reproductive performance were found between treatments (P > 0.05). It was evident that exposure of day-old ostriches to extensive human presence and interaction as chicks did not influence carcass attributes, meat quality or skin traits at slaughter age, but more importantly, it did not compromise their reproductive performance.

Ostrich ejaculate characteristics and male libido around equinox and solstice dates.

The study evaluated the effect of time of the year in which changes in photoperiod occurs on ostrich semen characteristics and male libido. Semen was collected for 5 days before, on and 5 days after winter solstice (21 June 2016), spring equinox (22 September 2016), summer solstice (21 December 2016) and autumn equinox (20 March 2017) in the southern hemisphere. Semen was collected from 10 South African Black ostrich males (average age ± standard deviation; 4.5 ± 2.27 years) using the dummy female. Semen volume, sperm concentration, total sperm per ejaculate, sperm motility traits, percentage of normal sperm, head and tail abnormalities and percentage of affected sperm in the hypo-osmotic swelling test (HOS) were evaluated. Male libido defined as the willingness of males to mount the dummy female was also recorded. Semen samples collected around summer solstice, spring and autumn equinox were higher in sperm concentration and sperm output compared with winter solstice (P < 0.05). Study periods did not influence semen volume, sperm motility traits, the percentage of normal sperm, head abnormalities and HOS. Tail abnormalities were higher around winter solstice than around spring equinox (P < 0.05). Male libido and the success of semen collection were significantly higher around spring equinox (P < 0.05). Changes in photoperiod in the southern hemisphere do not affect semen production in ostriches. However, high sperm output and male libido around spring equinox and summer solstice dates suggest that these periods may be preferred for semen collection for artificial insemination and storage purposes.

Sperm macrocephaly syndrome in the ostrich Struthio camelus: morphological characteristics and implications for motility.

Sperm macrocephaly syndrome (SMS) is characterised by a high percentage of spermatozoa with enlarged heads and multiple tails, and is related to infertility. Although this multiple sperm defect has been described in other mammalian species, little is known about this anomaly in birds. Morphological examination of semen from nine South African black ostriches (Struthio camelus var. domesticus) involved in an AI trial revealed the variable presence of spermatozoa with large heads and multiple tails. Ultrastructural features of the defect were similar to those reported in mammals except that the multiple tails were collectively bound within the plasmalemma. The tails were of similar length and structure to those of normal spermatozoa, and the heads were 1.6-fold longer, emphasising the uniformity of the anomaly across vertebrate species. Flow cytometry identified these cells as diploid and computer-aided sperm analysis revealed that they swim slower but straighter than normal spermatozoa, probably due to the increased drag of the large head and constrained movement of the merged multiple tails. The high incidence of this defect in one male ostrich indicates that, although rare, SMS can occur in birds and may potentially have an adverse effect on breeding programs, particularly for endangered species.

Computational simulation of electromagnetic fields on human targets for magnetic targeting applications.

In the last few years, the use of nanoparticles for therapeutic applications has attracted the interest of many scientists, who are looking for effective methods to target nanoparticles linked to drugs directly to the diseased organs. Among them, magnetic targeting consists of magnetic systems (magnets or coils) which can impress high gradient magnetic fields and then magnetic forces on the magnetic nanoparticles. Despite some studies have reported an effective improvement in drug delivery by using this technique, there is still a paucity of studies able to quantify and explain the experimental results. In this scenario, "in silico" models allow to analyze and compare different magnetic targeting systems in their ability to generate the required magnetic field gradient for specific human targets.In this paper we then evaluated, by means of computational electromagnetics techniques, the attitude of various ad-hoc designed magnetic systems in targeting the heart tissues of differently aged human anatomical models.

Assessment of Children Exposure Variability to Near-Field Sources using Stochastic Dosimetry.

In this paper, the exposure of a child to a hairdryer model is evaluated. Nowadays, the assessment of children exposure to near-field sources has become in fact a topic of high interest, because it was found that even domestic appliances could be relevant for children exposure level. Therefore, the aim of the present work is to use a method based on stochastic dosimetry to assess the exposure variability due to near-field sources, not limiting it only on some worst-case exposure scenario. In particular, electric field amplitudes induced in specific tissues composing the central nervous system and the peripheral nervous system (following the ICNIRP guidelines) were analyzed. The results highlight a high exposure variability depending on the hairdryer position in respect with the child.

Mineral profiling of ostrich (Struthio camelus) seminal plasma and its relationship with semen traits and collection day.

Successful assisted reproduction techniques, with specific focus on in vitro semen storage for artificial insemination, are dependent on certain key elements which includes the biochemical profiling of semen. The objective of this study was to complete an ostrich seminal plasma (SP) evaluation by inductively coupled plasma mass spectrometry (ICP-MS) among seven males at different daily intervals (day 1, 3, 7, 11, 15, 19, 21, 23, 25, 26, 27, 28) for a period of 28 days during spring (August to September) for mineral profiling. The effect of collection day and male on sperm concentration, semen volume and seminal plasma volume, was explored as well as the relationships amongst these specific sperm traits and SP minerals. Variation amongst SP mineral concentrations, accounted for by the fixed effects of sperm concentration, semen volume, seminal plasma volume, collection day and male, ranged from 18% to 77%. Male had the largest effect on variation in SP minerals, namely: phosphorus (P), potassium (K), calcium (Ca), sodium (Na), boron (B), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), barium (Ba), arsenic (As) and selenium (Se). Sperm concentration instigated fluctuations of P, magnesium (Mg), B, zinc (Zn), Fe, aluminium (Al), Se, manganese (Mn) and lead (Pb). Semen volume had an effect on Na, K, B, Pb and Ba while seminal plasma volume only influenced variation in Na. There were fluctuations among collection days of specific micro minerals, Ni and Mo, with initial Ni concentrations being relatively greater and Mo at lesser concentrations. Semen volume, seminal plasma volume and sperm concentration varied amongst males. Sperm concentrations during the initial collection days, 1 and 3, were less than that for days 7 to 28. Significant variation of SP minerals and sperm characteristics among ejaculates and males suggest an association of these specific elements with sperm function and are, therefore, considered to be of potential importance to success of assisted reproduction technology for the ostrich. The relationship amongst sperm concentration and collection day confirms the need to conduct an initial period of collection to stabilise a greater sperm concentration to optimise sperm numbers for artificial insemination purposes.

Ostrich specific semen diluent and sperm motility characteristics during in vitro storage.

The dilution of semen is a very important initial process for semen processing and evaluation, storage and preservation in vitro and efficient artificial insemination. The aim of the study was to evaluate the effect of two synthetic diluents (OS1 and OS2) on ostrich sperm motility parameters during in vitro storage. Formulation of OS1 was based on macro minerals (Na, K, P, Ca, Mg) and OS2 on the further addition of micro minerals (Se and Zn), based on mineral concentration determined in the ostrich seminal plasma (SP). Sperm motility was evaluated at different processing stages (neat, after dilution, during storage and after storage) by measuring several sperm motility variables using the Sperm Class Analyzer® (SCA). Processing (dilution, cooling and storage) of semen for in vitro storage purposes decreased the values for all sperm motility variables measured. The percentage motile (MOT) and progressive motile (PMOT) sperm decreased 20% to 30% during 24 h of storage, independent of diluent type. Quality of sperm swim (LIN, STR and WOB), however, was sustained during the longer storage periods (48 h) with the OS2 diluent modified with Se and Zn additions. Quality of sperm swim with use of OS1 was 6% to 8% less for the LIN, STR, and WOB variables. Male fitted as a fixed effect accounted for >60% of the variation for certain sperm motility variables (PMOT, MOT, VCL, VSL, VAP and ALH) evaluated at different processing stages. Semen from specific males had sustained sperm motility characteristics to a greater extent than that of other males during the 24-h storage period.

Neuromuscular training reduces lower limb injuries in elite female basketball players. A cluster randomized controlled trial.

The study was a two-armed, parallel group, cluster randomized controlled trial in which 15 teams (160 players) were assigned to either an experimental group (EG, 8 teams n = 86), which warmed-up with bodyweight neuromuscular exercises, or a control group (CG, 7 teams, n = 74) that performed standard tactical-technical exercises before training. All injuries during the 2015-2016 regular season were counted. Epidemiologic incidence proportion and incidence rate were also calculated. Countermovement jump (CMJ) and composite Y-Excursion Balance test (YBT) were used to assess lower limb strength and postural control. A total of 111 injuries were recorded. Chi-square test detected statistically significant differences between EG and CG (32 vs 79, P = .006). Significant differences in the injuries sustained in the EG (21 vs 11, P = .024) and CG (52 vs 27, P = .0001) during training and matches, respectively, were observed. Significant differences in post-intervention injuries were observed between in EG and CG during training (21 vs 52, P < .0001) and matches (11 vs 27, P = .006). Significant differences in epidemiologic incidence (0.37 vs 1.07, P = .023) and incidence rate (1.66 vs 4.69, P = .012) between the EG and the CG were found. Significant improvement in CMJ (+9.4%, P < .0001; d = 1.2) and composite YBT (right: +4.4%, P = .001, d = 1.0; left: +3.0%, P = .003; d = 0.8) for the EG was noted. Significant differences in post-intervention CMJ (+5.9%, P = .004) and composite YBT scores (right, +3.7%, P = .012; left, +2.3%, P = .007) between the EG and the CG were observed. Including bodyweight neuromuscular training into warm-up routines reduced the incidence of serious lower limb injuries in elite female basketball players.

Classification of ostrich sperm characteristics.

The success of assisted reproduction techniques is dependent on a sound foundation of understanding sperm characteristics to evaluate so as to improve semen processing. This study offers a descriptive basis for ostrich semen quality in terms of sperm function characteristics (SFC) that include motility, measured by computer assisted sperm analysis CASA (SCA(®)), viability (SYBR14/PI) and membrane integrity (hypo-osmotic swelling test). Relationships among these SFC's were explored and described by correlations and regressions. Certain fixed effects including the dilution of semen, season, year and male associated with semen collection were interpreted for future applications. The seasonal effect on sperm samples collected throughout the year suggested that it is prudent to restrict collections to spring and summer when SFC's and sperm concentration are maximized, compared to winter when these aspects of sperm quality are suppressed. Dilution of ejaculates helped to maintain important SFC's associated with fertilization success. The SFC's and sperm concentration varied among males, with specific males, having greater values for the percentage of motile (MOT) and progressively motile (PMOT) sperm, as well as sperm velocity (VCL, VSL, VAP) and linearity (LIN) variables. Males may thus be screened on these variables for inclusion in an artificial insemination (AI) programme to optimize fertility success rates.

Description of a model to optimise the feeding of amino acids to growing pullets.

1. A nutrition model is described that may be used to optimise the amino acid nutrition of laying-type pullets prior to the onset of lay. It is not a method of optimising lifetime laying performance. 2. The potential growth and composition of the body, feathers, ovary and oviduct are described from hatching to the age at which sexual maturity is attained, from which the daily amino acid and energy requirements for the average individual in the population can be calculated. 3. There are two parts to the approach used, the first being a description of the model itself and the second being a description of how the required information was gathered. A number of assumptions made in developing the model are discussed. 4. The rates of maturing of the body, feather-free body and body protein of the DeKalb pullets used were shown to be constant at 0.017/d and those of feathers at 0.02/d. These are considerably slower than those of the oviduct and ovary (0.139 and 0.084/d respectively). The ovary attained a higher mature weight (78.4 vs. 58.7 g) than the oviduct. 5. The age at which the growth of the reproductive organs is initiated in the model is defined by the user. The daily amount of threonine required to meet the requirements for maintenance and potential growth of the developing tissues and organs is calculated for each day of the growing period from hatching to the age at which the first egg is laid. A method of calculating the required daily concentration of threonine in the feed is described, from which a feeding programme may be derived. 6. For the model to produce an optimum economic feeding programme for a population of laying-type pullets, more information than is available from this study is required. These issues are discussed in the paper.

Whistle characteristics of the spinner dolphin population in the Comoros Archipelago.

Observed variations in dolphin acoustic signals may be associated with behavior, social composition, and local differences in habitat features. This study aims at characterizing whistles emitted by the spinner dolphin population occurring in the waters of the main island of the Archipelago of Comoros (Mozambique Channel, Indian Ocean) and to assess factors possibly influencing the acoustic structure of signals. All parameters examined on 953 whistles significantly differed in relation to environmental conditions, group size, and behavior. By mixed model analysis, it was found that only habitat characteristics play a role in the variation of frequency parameters, and exerted on the acoustic structure of whistles stronger influence than socio-behavioral factors. Spinner dolphins occurring in the Comoros archipelago use higher frequencies and show longer signal duration compared to those from the Pacific and the Atlantic. Results suggest that frequency parameters are distinctive of the local population and reflect the habitat use of the species in the area. In conclusion, acoustic measurements may be crucial elements to be included in monitoring programs to identify local peculiarities of dolphins' populations.

The response to dietary threonine in laying-type pullets during growth.

1. This study aimed to provide information on the response of laying-type pullets to dietary threonine (THR) during three periods of growth prior to the onset of lay. Different batches of Dekalb White pullets were used in three separate trial periods (from 4 to 6, 8 to 11 and 13 to 16 weeks of age) using 8 dietary THR concentrations in each period, using a completely randomised design, and with each treatment being replicated 6 times, using 15 birds per replication in period 1 and 8 birds in periods 2 and 3. In period 1 the THR content (THRc) ranged from 2.3 to 7.6 mg/g, in period 2 from 1.7 to 5.5 mg/g, and in period 3 from 1.4 to 4.7 mg THR/g feed. 2. Body weight gain, food intake and the deposition of protein and lipid in the feather-free body and in the feathers were measured in each period. Linear regressions were fitted to all data falling below the break point defined by the broken stick regression, to estimate the efficiency of utilisation of THR. The maximum protein growth rate was 4.0 ± 0.2, 5.3 ± 0.4 and 3.5 ± 0.5 g/d in periods 1, 2 and 3, respectively. 3. The efficiency of utilisation of dietary THR for THR deposition in each period was the same, at 0.85 ± 0.1 mg/mg. As dietary THRc decreased, the amount of body lipid deposition increased. 4. With this information, it is possible to determine the daily requirement for THR for the potential growth of body and feather protein in growing pullets.