Are we missing mumps epididymo-orchitis?

PubMed

Emerson, C; Dinsmore, W W; Quah, S P

2007-05-01

Mumps epididymo-orchitis has not been recorded as a cause of testicular symptoms without systemic features (including parotitis). The aim of the present study was to assess if we were missing cases in the genitourinary clinic during a previous outbreak of mumps in the community. During a prospective pilot study from November 2005 to February 2006, all patients presenting with symptoms or signs of epididymo-orchitis were studied. These patients were assessed for previous exposure to mumps virus or vaccine, and any current evidence of systemic illness. All patients included had a full sexual health screen (loop test, chlamydia polymerase chain reaction [PCR], gonorrhoea culture, HIV and Venereal Disease Research Laboratory [test]/Treponema pallidum particle agglutination assay), urinary tract infection excluded by urinalysis and mid-stream specimen of urine (MSSU) and mumps serology (Immunoglobulin M [IgM] and Immunoglobulin G [IgG]) performed. Twenty-three patients met inclusion criteria. Their ages ranged from 16 to 50 years, average 30.8 years. All had symptoms of these, 18 had testicular pain, eight swelling, (four had both pain and swelling) and three also had dysuria. On examination, 12 had tenderness, seven swelling, (two both tenderness and swelling) and six had no signs. Seventeen denied history of mumps, one patient had a record of vaccination and five described fever. None had parotid swelling. Three patients were chlamydia PCR positive, two had candida cultured, three had non-specific urethritis (>10 polymorphonuclear leucocyte/high powered field) and 13 had negative sexually transmitted infection screen (one known HIV-positive). Three had positive IgM mumps serology and two were IgG-positive. It is important to include mumps in the differential of epididymo-orchitis and to be aware of outbreaks in the community that may present with genital symptoms, as the management and partner notification will be different.

NMR imaging of high-amylose starch tablets. 2. Effect of tablet size.

PubMed

Malveau, Cédric; Baille, Wilms E; Zhu, Xiao Xia; Marchessault, Robert H

2002-01-01

Carbohydrate polymers are widely used for pharmaceutical applications such as the controlled release of drugs. The swelling and water mobility in high-amylose starch tablets are important parameters to be determined for these applications. They have been studied at different time intervals by nuclear magnetic resonance imaging (NMRI) after the immersion of the samples in water. These tablets have a hydrophilic matrix, which swells anisotropically and forms a hydrogel in water. NMRI shows clearly the anisotropy of the water penetration and the swelling along the radial and axial dimensions of the tablets. Empirical relationships are established to describe the kinetics of water penetration and swelling of the tablets. Results show that water uptake and tablet swelling strongly depend on the size of the tablets. Gravimetric measurements of water uptake were also performed in comparison with the NMRI results.

Sleeping distance in relation to sexual state in the Arctic blue fox.

PubMed

Korhonen, H; Alasuutari, S

1992-01-01

The paper provides comparative data concerning sleeping distance in relation to sexual state and hierarchical dominance in the Arctic blue fox. Increasing levels of vulval swelling and electrical resistance of vaginal tract were inversely related to sleeping distance between the highest-ranking male and each female on heat. A mating pair typically slept no further than 50 cm from each other. One month after copulation, the distance was already more than 200-250 cm. It can be concluded that oestrus-associated changes in sexual hormone levels have an influence on observed changes in sleeping distance.

Modeling the controllable pH-responsive swelling and pore size of networked alginate based biomaterials.

PubMed

Chan, Ariel W; Neufeld, Ronald J

2009-10-01

Semisynthetic network alginate polymer (SNAP), synthesized by acetalization of linear alginate with di-aldehyde, is a pH-responsive tetrafunctionally linked 3D gel network, and has potential application in oral delivery of protein therapeutics and active biologicals, and as tissue bioscaffold for regenerative medicine. A constitutive polyelectrolyte gel model based on non-Gaussian polymer elasticity, Flory-Huggins liquid lattice theory, and non-ideal Donnan membrane equilibria was derived, to describe SNAP gel swelling in dilute and ionic solutions containing uni-univalent, uni-bivalent, bi-univalent or bi-bi-valent electrolyte solutions. Flory-Huggins interaction parameters as a function of ionic strength and characteristic ratio of alginates of various molecular weights were determined experimentally to numerically predict SNAP hydrogel swelling. SNAP hydrogel swells pronouncedly to 1000 times in dilute solution, compared to its compact polymer volume, while behaving as a neutral polymer with limited swelling in high ionic strength or low pH solutions. The derived model accurately describes the pH-responsive swelling of SNAP hydrogel in acid and alkaline solutions of wide range of ionic strength. The pore sizes of the synthesized SNAP hydrogels of various crosslink densities were estimated from the derived model to be in the range of 30-450 nm which were comparable to that measured by thermoporometry, and diffusion of bovine serum albumin. The derived equilibrium swelling model can characterize hydrogel structure such as molecular weight between crosslinks and crosslinking density, or can be used as predictive model for swelling, pore size and mechanical properties if gel structural information is known, and can potentially be applied to other point-link network polyelectrolytes such as hyaluronic acid gel.

Size-Tunable and Functional Core-Shell Structured Silica Nanoparticles for Drug Release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi, Fangli; Guo, Ya Nan; Liu, Jun

2010-02-18

Size-tunable silica cross-linked micellar core-shell nanoparticles (SCMCSNs) were successfully synthesized from a Pluronic nonionic surfactant (F127) template system with organic swelling agents such as 1,3,5-trimethylbenzene (TMB) and octanoic acid at room temperature. The size and morphology of SCMCSNs were directly evidenced by TEM imaging and DLS measurements (up to ~90 nm). Pyrene and coumarin 153 (C153) were used as fluorescent probe molecules to investigate the effect and location of swelling agent molecules. Papaverine as a model drug was used to measure the loading capacity and release property of nanoparticles. The swelling agents can enlarge the nanoparticle size and improve themore » drug loading capacity of nanoparticles. Moreover, the carboxylic acid group of fatty acid can adjust the release behavior of the nanoparticles.« less

Mathematical modelling of liquid transport in swelling pharmaceutical immediate release tablets.

PubMed

Markl, Daniel; Yassin, Samy; Wilson, D Ian; Goodwin, Daniel J; Anderson, Andrew; Zeitler, J Axel

2017-06-30

Oral dosage forms are an integral part of modern health care and account for the majority of drug delivery systems. Traditionally the analysis of the dissolution behaviour of a dosage form is used as the key parameter to assess the performance of a drug product. However, understanding the mechanisms of disintegration is of critical importance to improve the quality of drug delivery systems. The disintegration performance is primarily impacted by the hydration and subsequent swelling of the powder compact. Here we compare liquid ingress and swelling data obtained using terahertz pulsed imaging (TPI) to a set of mathematical models. The interlink between hydration kinetics and swelling is described by a model based on Darcy's law and a modified swelling model based on that of Schott. Our new model includes the evolution of porosity, pore size and permeability as a function of hydration time. Results obtained from two sets of samples prepared from pure micro-crystalline cellulose (MCC) indicate a clear difference in hydration and swelling for samples of different porosities and particle sizes, which are captured by the model. Coupling a novel imaging technique, such as TPI, and mathematical models allows better understanding of hydration and swelling and eventually tablet disintegration. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

An investigation on "nano-swelling" phenomenon during resist dissolution using in situ high-speed atomic force microscopy

NASA Astrophysics Data System (ADS)

Santillan, Julius Joseph; Itani, Toshiro

2017-03-01

This work focuses on the application of a high-speed atomic force microscope (HS-AFM) for the in situ observation / quantification of the resist dissolution process. Specifically, this paper discusses on the existence of what the authors refer to as "nano-swelling" which occurs in the extreme ultraviolet (EUV) exposed areas of a positive-tone chemically amplified resist, just before it dissolves into the aqueous tetramethylammonium hydroxide (TMAH) developer solution. In earlier experiments using typical EUVL resist materials (e.g. polyhydroxystyrene (PHS) polymer and hybrid PHS-methacryl polymer model resists), it was understood that nano-swelling is mainly material type-dependent. As shown in the investigations/results in this paper, nano-swelling has variations in the timing of occurrence and amount/size depending on the size of the dissolvable areas (i.e. larger dissolvable areas dissolve faster, swell more compared to smaller ones). Lastly, a comparison of surface analyses results of a resist pattern before, during, and after the occurrence of nano-swelling suggests the significant impact of these kinds of non-uniformities in the formation of line edge/line width roughness (LER/LWR).

Effect of solute atoms on swelling in Ni alloys and pure Ni under He + ion irradiation

NASA Astrophysics Data System (ADS)

Wakai, E.; Ezawa, T.; Imamura, J.; Takenaka, T.; Tanabe, T.; Oshima, R.

2002-12-01

The effects of solute atoms on microstructural evolutions have been investigated using Ni alloys under 25 keV He + irradiation at 500 °C. The specimens used were pure Ni, Ni-Si, Ni-Co, Ni-Cu, Ni-Mn and Ni-Pd alloys with different volume size factors. The high number densities of dislocation loops about 1.5×10 22 m -3 were formed in the specimens irradiated to 1×10 19 ions/m 2, and they were approximately equivalent, except for Ni-Si. The mean size of loops tended to increase with the volume size factor of solute atoms. In a dose of 4×10 20 ions/m 2, the swelling was changed from 0.2% to 4.5%, depending on the volume size factors. The number densities of bubbles tended to increase with the absolute values of the volume size factor, and the swelling increased with the volume size factors. This suggests that the mobility of helium and vacancy atoms may be influenced by the interaction of solute atoms with them.

Effect of cell size on the reaction of uranium acetate, mercuric chloride, and cyanogen iodide with a strain of Pseudomonas aeruginosa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernheim, F.

1971-09-01

The effects of uranium acetate, with and without the addition of NaCl, on the optical density and size of cells of Pseudomonas aeruginosa were compared with the effects of mercuric chloride and cyanogen iodide with and without the addition of NaCl. The addition of uranium acetate to the culture media caused the cells to swell rapidly, with the extent of the change dependent upon the time urarium was allowed to react with the cells before the addition of NaCl. A partial reversal of the effect of uranium on swelling was obtained by the addition of ATP or sodium phosphate. Bothmore » mercuric chloride and cyanogen iodide caused the cells to swell but the addition of phosphates had no effect on the amount of swelling. (CH)« less

Swelling, Structure, and Phase Stability of Soft, Compressible Microgels

NASA Astrophysics Data System (ADS)

Denton, Alan R.; Urich, Matthew

Microgels are soft colloidal particles that swell when dispersed in a solvent. The equilibrium particle size is governed by a delicate balance of osmotic pressures, which can be tuned by varying single-particle properties and externally controlled conditions, such as temperature, pH, ionic strength, and concentration. Because of their tunable size and ability to encapsulate dye or drug molecules, microgels have practical relevance for biosensing, drug delivery, carbon capture, and filtration. Using Monte Carlo simulation, we model suspensions of microgels that interact via Hertzian elastic interparticle forces and can expand or contract via trial size changes governed by the Flory-Rehner free energy of cross-linked polymer gels. We analyze the influence of particle compressibility and size fluctuations on bulk structural and thermal properties by computing swelling ratios, radial distribution functions, static structure factors, osmotic pressures, and freezing densities. With increasing density, microgels progressively deswell and their intrinsic polydispersity broadens, while compressibility acts to forestall crystallization. This work was supported by the National Science Foundation under Grant No. DMR- 1106331.

"You're naked, you're vulnerable": Sexual well-being and body image of women with lower limb lymphedema.

PubMed

Winch, Caleb J; Sherman, Kerry A; Smith, Katriona M; Koelmeyer, Louise A; Mackie, Helen; Boyages, John

2016-09-01

Lower-limb lymphedema is an incurable illness manifesting as visible swelling enlarging the leg(s) and/or feet, buttocks, and genitals. This study used semi-structured interviews and thematic analysis to explore sexual well-being among women with primary (congenital) lymphedema (n=11) or secondary lymphedema associated with gynecological cancer (n=8). Five themes (subthemes) summarized women's responses, with Attractiveness and Confidence (Publicly Unattractive, Privately Unconfident, Lymphedema or Aging?) describing women's central concern. These body image-related concerns accounted for sexual well-being in association with Partner Support (Availability of Support, Languages of Support, Fears About Support) and the degree of Functional Interruptions (Lymphedema in Context, Enduring Impacts, Overcoming Interruptions). Successful Lymphedema Coping (Control, Acceptance) and self-perceived ability to fulfill a valued Sexual Role also affected sexual well-being. Few differences between women with primary versus secondary lymphedema were evident. Lymphedema clinicians should screen for sexual concerns and have referral options available. Copyright © 2016 Elsevier Ltd. All rights reserved.

Theoretical analysis of swelling characteristics of cylindrical uranium dioxide fuel pins with a niobium - 1-percent-zirconium clad

NASA Technical Reports Server (NTRS)

Saltsman, J. F.

1973-01-01

The relations between clad creep strain and fuel volume swelling are shown for cylindrical UO2 fuel pins with a Nb-1Zr clad. These relations were obtained by using the computer code CYGRO-2. These clad-strain - fuel-volume-swelling relations may be used with any fuel-volume-swelling model, provided the fuel volume swelling is isotropic and independent of the clad restraints. The effects of clad temperature (over a range from 118 to 1642 K (2010 to 2960 R)), pin diameter, clad thickness and central hole size in the fuel have been investigated. In all calculations the irradiation time was 500 hours. The burnup rate was varied.

Charge-regularized swelling kinetics of polyelectrolyte gels: Elasticity and diffusion

NASA Astrophysics Data System (ADS)

Sen, Swati; Kundagrami, Arindam

2017-11-01

We apply a recently developed method [S. Sen and A. Kundagrami, J. Chem. Phys. 143, 224904 (2015)], using a phenomenological expression of osmotic stress, as a function of polymer and charge densities, hydrophobicity, and network elasticity for the swelling of spherical polyelectrolyte (PE) gels with fixed and variable charges in a salt-free solvent. This expression of stress is used in the equation of motion of swelling kinetics of spherical PE gels to numerically calculate the spatial profiles for the polymer and free ion densities at different time steps and the time evolution of the size of the gel. We compare the profiles of the same variables obtained from the classical linear theory of elasticity and quantitatively estimate the bulk modulus of the PE gel. Further, we obtain an analytical expression of the elastic modulus from the linearized expression of stress (in the small deformation limit). We find that the estimated bulk modulus of the PE gel decreases with the increase of its effective charge for a fixed degree of deformation during swelling. Finally, we match the gel-front locations with the experimental data, taken from the measurements of charged reversible addition-fragmentation chain transfer gels to show an increase in gel-size with charge and also match the same for PNIPAM (uncharged) and imidazolium-based (charged) minigels, which specifically confirms the decrease of the gel modulus value with the increase of the charge. The agreement between experimental and theoretical results confirms general diffusive behaviour for swelling of PE gels with a decreasing bulk modulus with increasing degree of ionization (charge). The new formalism captures large deformations as well with a significant variation of charge content of the gel. It is found that PE gels with large deformation but same initial size swell faster with a higher charge.

Self-Sealing Cementitious Materials by Using Water-Swelling Rubber Particles

PubMed Central

Lv, Leyang; Schlangen, Erik; Xing, Feng

2017-01-01

Water ingress into cracked concrete structures is a serious problem, as it can cause leakage and reinforcement corrosion and thus reduce functionality and safety of the structures. In this study, the application of water-swelling rubber particles for providing the cracked concrete a self-sealing function was developed. The feasibility of applying water-swelling rubber particles and the influence of incorporating water-swelling rubber particles on the mechanical properties of concrete was investigated. The self-sealing efficiency of water-swelling rubber particles with different content and particle size was quantified through a permeability test. The sealing effect of the water swelling rubber particles was monitored by X-ray computed tomography. The experimental results show that, by using 6% of these water swelling rubber particles as a replacement of aggregates in concrete, up to 64% and 61% decrease of water permeability was realized for 0.7 mm and 1.0 mm cracks. Furthermore, when the concrete cracks, the water swelling rubber particles can act as a crack bridging filler, preventing the crack from fully separating the specimens in two pieces. PMID:28829384

Influence of injected interstitials on the void swelling in two structural variants of 304L stainless steel induced by self-ion irradiation at 500 °C

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, C.; Garner, F. A.; Shao, L.

The two variants of AISI 304L stainless steel (SS) with different grain size distributions were ion irradiated at 500 °C to a peak dose of ~60 dpa. In the coarse-grained annealed variant, a peak swelling of ~12% was observed closer to the specimen surface rather than at the depth of peak displacement damage. The forward shift in depth between peak swelling and peak dose is proposed to be a consequence of suppression of void nucleation by injected interstitials. The swelling behavior in the front portion of the ion range mirrors that of neutron-induced swelling in this steel, exhibiting significant curvaturemore » with increasing dose as the swelling rate approaches the terminal swelling rate of 1%/dpa. Furthermore, an ultrafine grain variant of this steel produced by severely plastic deformation exhibits a similar suppression of void nucleation in the injected interstitial region, but also shows a significantly extended transient regime, not reaching the terminal swelling rate by 60 dpa.« less

Influence of injected interstitials on the void swelling in two structural variants of 304L stainless steel induced by self-ion irradiation at 500 °C

DOE PAGES

Sun, C.; Garner, F. A.; Shao, L.; ...

2017-03-28

The two variants of AISI 304L stainless steel (SS) with different grain size distributions were ion irradiated at 500 °C to a peak dose of ~60 dpa. In the coarse-grained annealed variant, a peak swelling of ~12% was observed closer to the specimen surface rather than at the depth of peak displacement damage. The forward shift in depth between peak swelling and peak dose is proposed to be a consequence of suppression of void nucleation by injected interstitials. The swelling behavior in the front portion of the ion range mirrors that of neutron-induced swelling in this steel, exhibiting significant curvaturemore » with increasing dose as the swelling rate approaches the terminal swelling rate of 1%/dpa. Furthermore, an ultrafine grain variant of this steel produced by severely plastic deformation exhibits a similar suppression of void nucleation in the injected interstitial region, but also shows a significantly extended transient regime, not reaching the terminal swelling rate by 60 dpa.« less

Effect of grain morphology on gas bubble swelling in UMo fuels – A 3D microstructure dependent Booth model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Shenyang; Burkes, Douglas; Lavender, Curt A.

2016-11-01

A three dimensional microstructure dependent swelling model is developed for studying the fission gas swelling kinetics in irradiated nuclear fuels. The model is extended from the Booth model [1] in order to investigate the effect of heterogeneous microstructures on gas bubble swelling kinetics. As an application of the model, the effect of grain morphology, fission gas diffusivity, and spatial dependent fission rate on swelling kinetics are simulated in UMo fuels. It is found that the decrease of grain size, the increase of grain aspect ratio for the grain having the same volume, and the increase of fission gas diffusivity (fissionmore » rate) cause the increase of swelling kinetics. Other heterogeneities such as second phases and spatial dependent thermodynamic properties including diffusivity of fission gas, sink and source strength of defects could be naturally integrated into the model to enhance the model capability.« less

Swelling Kinetics of Waxy Maize Starch

NASA Astrophysics Data System (ADS)

Desam, Gnana Prasuna Reddy

Starch pasting behavior greatly influences the texture of a variety of food products such as canned soup, sauces, baby foods, batter mixes etc. The annual consumption of starch in the U.S. is 3 million metric tons. It is important to characterize the relationship between the structure, composition and architecture of the starch granules with its pasting behavior in order to arrive at a rational methodology to design modified starch of desirable digestion rate and texture. In this research, polymer solution theory was applied to predict the evolution of average granule size of starch at different heating temperatures in terms of its molecular weight, second virial coefficient and extent of cross-link. Evolution of granule size distribution of waxy native maize starch when subjected to heating at constant temperatures of 65, 70, 75, 80, 85 and 90 C was characterized using static laser light scattering. As expected, granule swelling was more pronounced at higher temperatures and resulted in a shift of granule size distribution to larger sizes with a corresponding increase in the average size by 100 to 120% from 13 mum to 25-28 mum. Most of the swelling occurred within the first 10 min of heating. Pasting behavior of waxy maize at different temperatures was also characterized from the measurements of G' and G" for different heating times. G' was found to increase with temperature at holding time of 2 min followed by its decrease at larger holding times. This behavior is believed to be due to the predominant effect of swelling at small times. However, G" was insensitive to temperature and holding times. The structure of waxy maize starch was characterized by cryoscanning electron microscopy. Experimental data of average granule size vs time at different temperatures were compared with model predictions. Also the Experimental data of particle size distribution vs particle size at different times and temperatures were compared with model predictions.

Traumatic brain injury and hemorrhagic shock: evaluation of different resuscitation strategies in a large animal model of combined insults.

PubMed

Jin, Guang; DeMoya, Marc A; Duggan, Michael; Knightly, Thomas; Mejaddam, Ali Y; Hwabejire, John; Lu, Jennifer; Smith, William Michael; Kasotakis, Georgios; Velmahos, George C; Socrate, Simona; Alam, Hasan B

2012-07-01

Traumatic brain injury (TBI) and hemorrhagic shock (HS) are the leading causes of trauma-related mortality and morbidity. Combination of TBI and HS (TBI + HS) is highly lethal, and the optimal resuscitation strategy for this combined insult remains unclear. A critical limitation is the lack of suitable large animal models to test different treatment strategies. We have developed a clinically relevant large animal model of TBI + HS, which was used to evaluate the impact of different treatments on brain lesion size and associated edema. Yorkshire swine (42-50 kg) were instrumented to measure hemodynamic parameters and intracranial pressure. A computer-controlled cortical impact device was used to create a TBI through a 20-mm craniotomy: 15-mm cylindrical tip impactor at 4 m/s velocity, 100-ms dwell time, and 12-mm penetration depth. Volume-controlled hemorrhage was started (40% blood volume) concurrent with the TBI. After 2 h of shock, animals were randomized to one of three resuscitation groups (n = 5/group): (a) normal saline (NS); (b) 6% hetastarch, Hextend (Hex); and (c) fresh frozen plasma (FFP). Volumes of Hex and FFP matched the shed blood, whereas NS was three times the volume. After 6 h of postresuscitation monitoring, brains were sectioned into 5-mm slices and stained with TTC (2,3,5-triphenyltetrazolium chloride) to quantify the lesion size and brain swelling. Combination of 40% blood loss with cortical impact and a period of shock (2 h) resulted in a highly reproducible brain injury. Total fluid requirements were lower in the Hex and FFP groups. Lesion size and brain swelling in the FFP group (2,160 ± 202.63 mm and 22% ± 1.0%, respectively) were significantly smaller than those in the NS group (3,285 ± 130.8 mm3 and 37% ± 1.6%, respectively) (P < 0.05). Hex treatment decreased the swelling (29% ± 1.6%) without reducing the lesion size. Early administration of FFP reduces the size of brain lesion and associated swelling in a large animal model of TBI + HS. In contrast, artificial colloid (Hex) decreases swelling without reducing the actual size of the brain lesion.

My 'Fat Girl Complex': a preliminary investigation of sexual health and body image in women of size.

PubMed

Satinsky, Sonya; Dennis, Barbara; Reece, Michael; Sanders, Stephanie; Bardzell, Shaowen

2013-01-01

Women of size who inhabit non-normative bodies may have different experiences with body image and sexual health than women of average body size. In this exploratory study, we interviewed four women of size recruited from a larger mixed-methodological study of body image and sexuality. Each woman was interviewed twice on topics of body image, sexuality and sexual health. Reconstructive Horizon Analysis was used to analyse the content of the interviews. Women who expressed that their bodies had inherent personal and social value regardless of size did not articulate connections between body size and their sexual health. However, those women who looked externally for validation of their attractiveness struggled with acceptance of their sexuality and bodies and spoke of ways in which their body size and appearance hindered them from having the sexually healthy lives that they wanted. Findings highlight two important components of women's sexual health as participants related them to body image: the right to pleasure and the right to engage only in wanted sexual activity. Participants described how negative body attitudes affected both of these aspects of their sexual health. Interventions targeting weight-based stigma may offer a means of indirectly promoting sexual health and autonomy in women.

Optical scatter imaging of cellular and mitochondrial swelling in brain tissue models of stroke

NASA Astrophysics Data System (ADS)

Johnson, Lee James

2001-08-01

The severity of brain edema resulting from a stroke can determine a patient's survival and the extent of their recovery. Cellular swelling is the microscopic source of a significant part of brain edema. Mitochondrial swelling also appears to be a determining event in the death or survival of the cells that are injured during a stroke. Therapies for reducing brain edema are not effective in many cases and current treatments of stroke do not address mitochondrial swelling at all. This dissertation is motivated by the lack of a complete understanding of cellular swelling resulting from stroke and the lack of a good method to begin to study mitochondrial swelling resulting from stroke in living brain tissue. In this dissertation, a novel method of detecting mitochondrial and cellular swelling in living hippocampal slices is developed and validated. The system is used to obtain spatial and temporal information about cellular and mitochondrial swelling resulting from various models of stroke. The effect of changes in water content on light scatter and absorption are examined in two models of brain edema. The results of this study demonstrate that optical techniques can be used to detect changes in water content. Mie scatter theory, the theoretical basis of the dual- angle scatter ratio imaging system, is presented. Computer simulations based on Mie scatter theory are used to determine the optimal angles for imaging. A detailed account of the early systems is presented to explain the motivations for the system design, especially polarization, wavelength and light path. Mitochondrial sized latex particles are used to determine the system response to changes in scattering particle size and concentration. The dual-angle scatter ratio imaging system is used to distinguish between osmotic and excitotoxic models of stroke injury. Such distinction cannot be achieved using the current techniques to study cellular swelling in hippocampal slices. The change in the scatter ratio is then shown to correlate to mitochondrial swelling, as observed with electron microscopy. The system is finally used to study mitochondrial and cellular swelling. Evidence of the susceptibility of certain hippocampal regions, CA1 and the dentate gyrus, to exhibit mitochondrial swelling as the result of oxygen and glucose deprivation is presented. In addition, for the first time, the time course of mitochondrial swelling is seen. Finally, experiments with scatter imaging and measurement of nitric oxide with carbon fiber electrodes demonstrate a clear link between nitric oxide and cellular swelling. A potential mechanism of the action of nitric oxide is evaluated. Nitric oxide appears to act to cause cellular swelling without the release of glutamate. The use of targeted nitric oxide inhibitors may be useful for the reduction of edema.

Swelling and tribological properties of melt-mixed fluoroelastomer/nitrile rubber blends under crude oil

NASA Astrophysics Data System (ADS)

Tagelsir, Yasin; Li, San-Xi; Lv, Xiaoren; Wang, Shijie; Wang, Song; Osman, Zeinab

2018-01-01

The melt-mixed fluoroelastomer (FKM)/ nitrile rubber (NBR) blends of (90/10, 80/20, 70/30, 60/40 and 50/50) ratios with same hardness were prepared, and their swelling and tribological properties under crude oil were investigated for the purpose of developing high performance cost-effective elastomers meeting requirement of oil extraction progressive cavity pump stator. Differential scanning calorimetry confirmed compatible blend system for all blends. Field emission scanning electron microscopy (FE-SEM) showed co-continuous morphology of 200-400 nm phase size for all blends, expect FKM/NBR (90/10) which exhibited partially continuous phase morphology of 100-250 nm phase size. The results of swelling and linear wear tests under crude oil indicated that swelling percentage, coefficient of friction and specific wear rate of FKM/NBR blends were much better than NBR, with FKM/NBR (90/10 and 80/20) showing swelling percentage and specific wear rate very close to FKM. Attenuated total reflectance-Fourier transform infrared spectroscopy disclosed that fracture of macromolecular chains was the main mechanochemical effect of unswollen and swollen worn surfaces, in addition to oxygenated degradation detected with increasing NBR ratio in the blends. The fracture of macromolecular chains resulted in slight fatigue wear mechanism, which was also confirmed by FE-SEM of the worn surfaces.

Dramatic reduction of void swelling by helium in ion-irradiated high purity α-iron

DOE PAGES

Bhattacharya, Arunodaya; Meslin, Estelle; Henry, Jean; ...

2018-04-11

Effect of helium on void swelling was studied in high-purity α-iron, irradiated using energetic self-ions to 157 displacements per atom (dpa) at 773 K, with and without helium co-implantation up to 17 atomic parts-per-million (appm) He/dpa. Helium is known to enhance cavity formation in metals in irradiation environments, leading to early void swelling onset. In this study, microstructure characterization by transmission electron microscopy revealed compelling evidence of dramatic swelling reduction by helium co-implantation, achieved primarily by cavity size reduction. In conclusion, a comprehensive understanding of helium induced cavity microstructure development is discussed using sink strength ratios of dislocations and cavities.

An improved correlation to predict molecular weight between crosslinks based on equilibrium degree of swelling of hydrogel networks.

PubMed

Jimenez-Vergara, Andrea C; Lewis, John; Hahn, Mariah S; Munoz-Pinto, Dany J

2018-04-01

Accurate characterization of hydrogel diffusional properties is of substantial importance for a range of biotechnological applications. The diffusional capacity of hydrogels has commonly been estimated using the average molecular weight between crosslinks (M c ), which is calculated based on the equilibrium degree of swelling. However, the existing correlation linking M c and equilibrium swelling fails to accurately reflect the diffusional properties of highly crosslinked hydrogel networks. Also, as demonstrated herein, the current model fails to accurately predict the diffusional properties of hydrogels when polymer concentration and molecular weight are varied simultaneously. To address these limitations, we evaluated the diffusional properties of 48 distinct hydrogel formulations using two different photoinitiator systems, employing molecular size exclusion as an alternative methodology to calculate average hydrogel mesh size. The resulting data were then utilized to develop a revised correlation between M c and hydrogel equilibrium swelling that substantially reduces the limitations associated with the current correlation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1339-1348, 2018. © 2017 Wiley Periodicals, Inc.

Characterization and swelling-deswelling properties of wheat straw cellulose based semi-IPNs hydrogel.

PubMed

Liu, Jia; Li, Qian; Su, Yuan; Yue, Qinyan; Gao, Baoyu

2014-07-17

A novel wheat straw cellulose-g-poly(potassium acrylate)/polyvinyl alcohol (WSC-g-PKA/PVA) semi-interpenetrating polymer networks (semi-IPNs) hydrogel was prepared by polymerizing wheat straw and an aqueous solution of acrylic acid (AA), and further semi-interpenetrating with PVA occurred during the chemosynthesis. The swelling and deswelling properties of WSC-g-PKA/PVA semi-IPNs hydrogel and WSC-g-PKA hydrogel were studied and compared in various pH solutions, salt solutions, temperatures, particle sizes and ionic strength. The results indicated that both hydrogels had the largest swelling capacity at pH=6, and the effect of ions on the swelling of hydrogels was in the order: Na(+)>K(+)>Mg(2+)>Ca(2+). The Schott's pseudo second order model can be effectively used to evaluate swelling kinetics of hydrogels. Moreover, the semi-IPNs hydrogel had improved swelling-deswelling properties compared with that of WSC-g-PKA hydrogel. Copyright © 2014 Elsevier Ltd. All rights reserved.

Africa's Megafans and Their Tectonic Setting

NASA Technical Reports Server (NTRS)

Wilkinson, M. J.; Burke, K.

2016-01-01

Megafans are a really extensive continental sediment bodies, fluvially derived, and fan-shaped in planform. Only those >80 km long were included in this study. Africa's megafans were mapped for purposes of both comprehensive geomorphic description and as a method of mapping by remote sensing large probable fluvial sediment bodies (we exclude sediment bodies deposited in well defined, modern floodplains and coastal deltas). Our criteria included a length dimension of >80 km and maximum width >40 km, partial cone morphology, and a radial drainage pattern. Visible and especially IR imagery were used to identify the features, combined with topographic SRTM data. We identified 99 megafans most of which are unstudied thus far. Their feeder rivers responsible for depositing megafan sediments rise on, and are consequent drainages oriented down the slopes of the swells that have dominated African landscapes since approximately 34 Ma (the high points in Africa's so-called basin-and-swell topography [1]). Most megafans (66%) have developed along these consequent rivers relatively near the swell cores, oriented radially away from the swells. The vast basins between the swells provide accommodation for megafan sediment wedges. Although clearly visible remotely, most megafans are inactive as a result of incision by the feeder river (which then no longer operates on the fan surface). Two tectonic settings control the location of Africa's megafans, 66% on swell flanks, and 33% related to rifts. (i) Swell flanks Most megafans are apexed relatively near the core of the parent swell, and are often clustered in groups: e.g., six on the west and north flanks of the Hoggar Swell (Algeria), seven on the north and south flanks of the Tibesti Swell (Libya-Chad borderlands), twelve on the west flank of the Ethiopian Swell, four on the east flank of the East African Swell (Kenya), Africa's largest, and eight around Angola's Bié Swell (western Zambia, northern Namibia). A cluster of possible fans lies on the western margin of the Congo Basin (Mayombe Swell), and on the coastal slopes of the Namibia Swell. Sheer size may have militated aginst the recognition of many megafans: the largest in the Sahara are the Teghahart (378 km, Hoggar Swell, Algeria), and the Wadi Albalata (340 km, Uweinat Swell, Egypt). In southern Africa the largest are the Cubango (320 km, Bié Swell, Angola/ Namibia), and the Limpopo (230 km, Mozambique). (ii) Rift zones (a) Steer's horns basins-wide depressions centered on rifts. The largest contiguous group (n=14) developed in a steer's-horns basin occupies the wide Muglad depression (200-350 km, South Sudan). Four rift-related megafans lie SE of Lake Chad (Chad). Nine megafans occupy the complex Anza Rift in Kenya/South Somalia. The Salamat megafan (Chad), is unusual because it oriented parallel with the linked Salamat, Doseo and Doba rift axes, and is consequently one of the longest in Africa (465 km). (b) Rift depressions sensu stricto. Most rifts are too narrow to provide a transverse dimension large enough to accommodate megafans. Although well-known, the Okavango Rift (NW Botswana, NE Namibia) is unique in Africa in hosting three megafans within identifiable faulted margins. The Nile megafan is Africa's largest (476 km) and comprises the vast Sudd wetland (South Sudan). An explanation for its remarkable size may be its location in a depression at the junction of two conducive tectonic zones, the East African Swell margin and the Muglad steer's-horns depression. Discharge of the River Nile, the largest in the region, has allowed the Nile megafan to outcompete neighboring megafans for space.

Embryology and anatomy of the vulva: the female orgasm and women's sexual health.

PubMed

Puppo, Vincenzo

2011-01-01

Sexual health is vital to overall well-being. Orgasm is a normal psycho-physiological function of human beings and every woman has the right to feel sexual pleasure. The anatomy of the vulva and of the female erectile organs (trigger of orgasm) is described in human anatomy textbooks. Female sexual physiology was first described in Dickinson's textbook in 1949 and subsequently by Masters and Johnson in 1966. During women's sexual response, changes occur in the congestive structures that are essential to the understanding of women's sexual response and specifically of their orgasm. Female and male external genital organs arise from the same embryologic structures, i.e. phallus, urogenital folds, urogenital sinus and labioscrotal swellings. The vulva is formed by the labia majora and vestibule, with its erectile apparatus: clitoris (glans, body, crura), labia minora, vestibular bulbs and corpus spongiosum. Grafenberg, in 1950, discovered no "G-spot" and did not report an orgasm of the intraurethral glands. The hypothetical area named "G-spot" should not be defined with Grafenberg's name. The female orgasm should be a normal phase of the sexual response cycle, which is possible to achieve by all healthy women with effective sexual stimulation. Knowledge of the embryology, anatomy and physiology of the female erectile organs are important in the field of women's sexual health. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Inhibition of VEGF Signaling Reduces Diabetes-Exacerbated Brain Swelling, but Not Infarct Size, in Large Cerebral Infarction in Mice.

PubMed

Kim, Eunhee; Yang, Jiwon; Park, Keun Woo; Cho, Sunghee

2017-12-30

In light of repeated translational failures with preclinical neuroprotection-based strategies, this preclinical study reevaluates brain swelling as an important pathological event in diabetic stroke and investigates underlying mechanism of the comorbidity-enhanced brain edema formation. Type 2 (mild), type 1 (moderate), and mixed type 1/2 (severe) diabetic mice were subjected to transient focal ischemia. Infarct volume, brain swelling, and IgG extravasation were assessed at 3 days post-stroke. Expression of vascular endothelial growth factor (VEGF)-A, endothelial-specific molecule-1 (Esm1), and the VEGF receptor 2 (VEGFR2) was determined in the ischemic brain. Additionally, SU5416, a VEGFR2 inhibitor, was treated in the type 1/2 diabetic mice, and stroke outcomes were determined. All diabetic groups displayed bigger infarct volume and brain swelling compared to nondiabetic mice, and the increased swelling was disproportionately larger relative to infarct enlargement. Diabetic conditions significantly increased VEGF-A, Esm1, and VEGFR2 expressions in the ischemic brain compared to nondiabetic mice. Notably, in diabetic mice, VEGFR2 mRNA levels were positively correlated with brain swelling, but not with infarct volume. Treatment with SU5416 in diabetic mice significantly reduced brain swelling. The study shows that brain swelling is a predominant pathological event in diabetic stroke and that an underlying event for diabetes-enhanced brain swelling includes the activation of VEGF signaling. This study suggests consideration of stroke therapies aiming at primarily reducing brain swelling for subjects with diabetes.

Ruptured superficial dorsal vein of the penis masquerading as a penile fracture: case report.

PubMed

Perlmutter, Adam E; Roberts, Lawrence; Farivar-Mohseni, Hesam; Zaslau, Stanley

2007-08-01

Acute onset of pain, swelling, and ecchymosis of the penis during sexual intercourse indicate a penile fracture until proven otherwise. However, there have been few case reports of isolated injuries to the dorsal penile artery or dorsal vein mimicking a penile fracture. Presented herein is a rare case of a patient who ruptured his superficial dorsal vein during intercourse.

Reduced reproductive function in wild baboons (Papio hamadryas anubis) related to natural consumption of the African black plum (Vitex doniana).

PubMed

Higham, James P; Ross, Caroline; Warren, Ymke; Heistermann, Michael; MacLarnon, Ann M

2007-09-01

Several authors have suggested that the consumption of plant compounds may have direct effects on wild primate reproductive biology, but no studies have presented physiological evidence of such effects. Here, for two troops of olive baboons (Papio hamadryas anubis) at Gashaka-Gumti National Park, Nigeria, we show major seasonal increases in levels of fecal progesterone metabolites in females, and provide evidence that this is linked to the consumption of natural plant compounds. Increases in fecal progestogen excretion occurred seasonally in all females, in all reproductive states, including lactation. Detailed feeding data on the study animals showed that only one food species is consumed by both troops at the time of observed progestogen peaks, and at no other times of the year: the African black plum, Vitex doniana. Laboratory tests demonstrated the presence of high concentrations of progestogen-like compounds in V. doniana. Together with published findings linking the consumption of a related Vitex species (Vitex agnus castus) to increased progestogen levels in humans, our data suggest that natural consumption of V. doniana was a likely cause of the observed increases in progestogens. Levels of progestogen excretion in the study baboons during periods of V. doniana consumption are higher than those found during pregnancy, and prevent the expression of the sexual swelling, which is associated with ovulatory activity. As consortship and copulatory activity in baboons occur almost exclusively in the presence of a sexual swelling, V. doniana appears to act on cycling females as both a physiological contraceptive (simulating pregnancy in a similar way to some forms of the human contraceptive pill) and a social contraceptive (preventing sexual swelling, thus reducing association and copulation with males). The negative effects of V. doniana on reproduction may be counter-balanced by the wide-range of medicinal properties attributed to plants in this genus. This is the first time that physiological evidence has been presented of direct effects of plant consumption on the reproductive biology of wild primates.

Sexual selection explains sex-specific growth plasticity and positive allometry for sexual size dimorphism in a reef fish

PubMed Central

Walker, Stefan P. W.; McCormick, Mark I.

2009-01-01

In 1950, Rensch noted that in clades where males are the larger sex, sexual size dimorphism (SSD) tends to be more pronounced in larger species. This fundamental allometric relationship is now known as ‘Rensch's rule’. While most researchers attribute Rensch's rule to sexual selection for male size, experimental evidence is lacking. Here, we suggest that ultimate hypotheses for Rensch's rule should also apply to groups of individuals and that individual trait plasticity can be used to test those hypotheses experimentally. Specifically, we show that in the sex-changing fish Parapercis cylindrica, larger males have larger harems with larger females, and that SSD increases with harem size. Thus, sexual selection for male body size is the ultimate cause of sexual size allometry. In addition, we experimentally illustrate a positive relationship between polygyny potential and individual growth rate during sex change from female to male. Thus, sexual selection is the ultimate cause of variation in growth rate, and variation in growth rate is the proximate cause of sexual size allometry. Taken together, our results provide compelling evidence in support of the sexual selection hypothesis for Rensch's rule and highlight the potential importance of individual growth modification in the shaping of morphological patterns in Nature. PMID:19553253

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharya, Arunodaya; Meslin, Estelle; Henry, Jean

Effect of helium on void swelling was studied in high-purity α-iron, irradiated using energetic self-ions to 157 displacements per atom (dpa) at 773 K, with and without helium co-implantation up to 17 atomic parts-per-million (appm) He/dpa. Helium is known to enhance cavity formation in metals in irradiation environments, leading to early void swelling onset. In this study, microstructure characterization by transmission electron microscopy revealed compelling evidence of dramatic swelling reduction by helium co-implantation, achieved primarily by cavity size reduction. In conclusion, a comprehensive understanding of helium induced cavity microstructure development is discussed using sink strength ratios of dislocations and cavities.

Sexual differences in post-hatching Saunders's gulls: size, locomotor activity, and foraging skill.

PubMed

Yoon, Jongmin; Lee, Seung-Hee; Joo, Eun-Jin; Na, Ki-Jeong; Park, Shi-Ryong

2013-04-01

Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

Linking natural microstructures with numerical modeling of pinch-and-swell structures

NASA Astrophysics Data System (ADS)

Peters, Max; Berger, Alfons; Herwegh, Marco; Regenauer-Lieb, Klaus

2016-04-01

For a variety of geological problems, the change from homogeneous to localized deformation and the establishment of steady-state conditions are equally important. Here, we show that pinch-and-swell structures are ideal candidates for the study of the switch in deformation style and mechanism during ductile creep. We present an interdisciplinary approach to the onset of pinch-and-swell structures and to the flow conditions during pre- to post-localization stages in ductile rocks. For this reason, naturally boudinaged calcite veins, embedded in a calc-mylonite, and their microfabrics were investigated quantitatively. Remnants of slightly deformed calcite hosts build up the swells, showing twinning and minor dislocation glide as crystal plastic deformation mechanisms which are accompanied by subgrain rotation recrystallization (SGR). Towards the pinches, we find a gradient of severe grain size reduction through progressive SGR, developing a characteristic dislocation creep crystallographic preferred orientation (CPO). Along this gradient, the finest recrystallized calcite grains appear randomly oriented, expressed by a "smearing-out" of the CPO and missing systematics of misorientation angles in the most extended areas. We interpret this microstructure as a switch from dislocation dominated creep to grain boundary sliding processes. Further, we show that the onset of boudinage is independent on both the original orientation and grain size of calcite hosts. We implemented these microstructural observations into a layered elasto-visco-plastic finite element framework, tracing variations in grain size (Peters et al., 2015). We base the microstructural evolution on thermo-mechanical-chemical principles and end-member flow laws (Herwegh et al., 2014). The simulated pinch-and-swell structures indicate that low strain rates in the swells favor dislocation creep, whereas accelerated rates provoke continuous grain size reduction allowing strain accommodation by diffusion creep dominated deformation at relatively high extensional strains in the pinches. The numerical simulations indicate that viscosity weakening due to dissipated heat from grain size reduction marks the onset of localization, resulting in continuous necking of the layer. Interestingly, there exist multiple steady states, i.e. a first homogeneous state out of which localization arises, steady states of the stable end-member structure, expressed by homogeneous conditions in both pinches and swells, and in the surrounding matrix, the latter obeying a linear rheology. Based on our microstructural and numerical results, we suggest that the onset of localization represents a fundamental material bifurcation. This implies that the studied structures can be described as ductile instabilities. Finally, we discuss the profound role of the energy theory of localization described here, which allows deriving the paleo-deformation conditions, as well as fundamental material properties in a self-consistent manner. REFERENCES Herwegh, M., Poulet, T., Karrech, A. and Regenauer-Lieb, K. (2014): Journal of Geophysical Research 119, doi:10.1002/2013JB010701 Peters, M., Veveakis, M., Poulet, T., Karrech, A., Herwegh, M. and Regenauer-Lieb, K. (2015): Journal of Structural Geology 78, doi:10.1016/j.jsg.2015.06.005

Improvement of Tenofovir vaginal release from hydrophilic matrices through drug granulation with hydrophobic polymers.

PubMed

Notario-Pérez, Fernando; Martín-Illana, Araceli; Cazorla-Luna, Raúl; Ruiz-Caro, Roberto; Peña, Juan; Veiga, María-Dolores

2018-05-30

Sustained-release vaginal microbicides hold out great hope for the prevention of sexual transmission of HIV from men to women. Tenofovir (TFV) -an antiretroviral drug- sustained-release vaginal compacts combining two release control systems (by drug-loading granules with hydrophobic polymers and incorporating them in a hydrophilic matrix) are proposed in this work as a possible microbicide. The polymers used for the drug granules are Eudragit® RS (ERS), an acrylic derivative, and Zein, a maize protein. The hydrophilic matrix is composed of a mixture of hydroxypropylmethyl cellulose (HPMC) and chitosan (CH). The thermal, microscopic, spectrophotometric and X-ray diffraction analysis showed that the drug was not altered during the granulation process. Studies of TFV release, swelling and ex vivo mucoadhesion were subsequently performed on simulated vaginal fluid. The formulation whereby TFV is granulated using twice its weight in ERS, and then including these granules in a matrix in which the CH predominates over HPMC, allows the sustained release of TFV for 144 h, mucoadhesion to the vaginal mucosa for 150 h and a moderate swelling, making it the most suitable formulation of all those studied. These compacts would therefore offer women protection against the sexual acquisition of HIV. Copyright © 2018 Elsevier B.V. All rights reserved.

Neck swelling due to skull base (pseudo)meningocele protruding through a congenital skull base bone defect: a case report.

PubMed

Sharma, Rajeev; Singh, Bhoopendra; Kedia, Shweta; Laythalling, Rajinder Kumar

2017-02-01

Meningocele is defined as a protrusion of the meninges through an opening in the skull or spinal column, forming a bulge or sac filled with cerebrospinal fluid. A pseudomeningocele is defined as a cerebrospinal fluid (CSF) collection formed due to escape of CSF through a dural defect with trapping of CSF into the surrounding soft tissues. We herby report rare occurrence of a large (pseudo)meningocele in a young patient with congenital skull base defect presenting as upper lateral neck swelling. We present the case of a 17-year-old boy who had painless progressive swelling right side of the upper neck without any history of meningitis or CSF leak. He had a history of undergoing cranioplasty using steel plates for nontraumatic boggy swelling right parieto-occipital region at the age of 5 years at another hospital. Clinical examination showed painless swelling right side of the upper neck, with positive cough impulse and transillumination. CT head with cisternography showed a large right skull base defect through which a large pseudomeningocele was herniating, thus producing upper neck swelling and compressing oral cavity. The neck swelling and intraoral bulge reduced in size after the coperitoneal shunt. Differential diagnosis of (pseudo)meningocele should be considered while evaluating a painless progressive upper neck swelling having cough impulse and transillumination in a young patient.

A test of the size-constraint hypothesis for a limit to sexual dimorphism in plants.

PubMed

Labouche, Anne-Marie; Pannell, John R

2016-07-01

In flowering plants, many dioecious species display a certain degree of sexual dimorphism in non-reproductive traits, but this dimorphism tends to be much less striking than that found in animals. Sexual size dimorphism in plants may be limited because competition for light in crowded environments so strongly penalises small plants. The idea that competition for light constrains the evolution of strong sexual size dimorphism in plants (the size-constraint hypothesis) implies a strong dependency of the expression of sexual size dimorphism on the neighbouring density as a result of the capacity of plants to adjust their reproductive effort and investment in growth in response to their local environment. Here, we tested this hypothesis by experimentally altering the context of competition for light among male-female pairs of the light-demanding dioecious annual plant Mercurialis annua. We found that males were smaller than females across all treatments, but sexual size dimorphism was diminished for pairs grown at higher densities. This result is consistent with the size-constraint hypothesis. We discuss our results in terms of the tension between selection on size acting in opposite directions on males and females, which have different optima under sexual selection, and stabilizing selection for similar sizes in males and females, which have similar optima under viability selection for plasticity in size expression under different density conditions.

Anal signs of child sexual abuse: a case-control study.

PubMed

Hobbs, Christopher J; Wright, Charlotte M

2014-05-27

There is uncertainty about the nature and specificity of physical signs following anal child sexual abuse. The study investigates the extent to which physical findings discriminate between children with and without a history of anal abuse. Retrospective case note review in a paediatric forensic unit. all eligible cases from 1990 to 2007 alleging anal abuse. all children examined anally from 1998 to 2007 with possible physical abuse or neglect with no identified concern regarding sexual abuse. Fisher's exact test (two-tailed) was performed to ascertain the significance of differences for individual signs between cases and controls. To explore the potential role of confounding, logistic regression was used to produce odds ratios adjusted for age and gender. A total of 184 cases (105 boys, 79 girls), average age 98.5 months (range 26 to 179) were compared with 179 controls (94 boys, 85 girls) average age 83.7 months (range 35-193). Of the cases 136 (74%) had one or more signs described in anal abuse, compared to 29 (16%) controls. 79 (43%) cases and 2 (1.1%) controls had >1 sign. Reflex anal dilatation (RAD) and venous congestion were seen in 22% and 36% of cases but <1% of controls (likelihood ratios (LR) 40, 60 respectively), anal fissure in 14% cases and 1.1% controls (LR 13), anal laxity in 27% cases and 3% controls (LR 10).Novel signs seen significantly more commonly in cases were anal fold changes, swelling and twitching. Erythema, swelling and fold changes were seen most commonly within 7 days of last reported contact; RAD, laxity, venous congestion, fissure and twitching were observed up to 6 months after the alleged assault. Anal findings are more common in children alleging anal abuse than in those presenting with physical abuse or neglect with no concern about sexual abuse. Multiple signs are rare in controls and support disclosed anal abuse.

Anal signs of child sexual abuse: a case–control study

PubMed Central

2014-01-01

Background There is uncertainty about the nature and specificity of physical signs following anal child sexual abuse. The study investigates the extent to which physical findings discriminate between children with and without a history of anal abuse. Methods Retrospective case note review in a paediatric forensic unit. Cases: all eligible cases from1990 to 2007 alleging anal abuse. Controls: all children examined anally from 1998 to 2007 with possible physical abuse or neglect with no identified concern regarding sexual abuse. Fisher’s exact test (two-tailed) was performed to ascertain the significance of differences for individual signs between cases and controls. To explore the potential role of confounding, logistic regression was used to produce odds ratios adjusted for age and gender. Results A total of 184 cases (105 boys, 79 girls), average age 98.5 months (range 26 to 179) were compared with 179 controls (94 boys, 85 girls) average age 83.7 months (range 35–193). Of the cases 136 (74%) had one or more signs described in anal abuse, compared to 29 (16%) controls. 79 (43%) cases and 2 (1.1%) controls had >1 sign. Reflex anal dilatation (RAD) and venous congestion were seen in 22% and 36% of cases but <1% of controls (likelihood ratios (LR) 40, 60 respectively), anal fissure in 14% cases and 1.1% controls (LR 13), anal laxity in 27% cases and 3% controls (LR 10). Novel signs seen significantly more commonly in cases were anal fold changes, swelling and twitching. Erythema, swelling and fold changes were seen most commonly within 7 days of last reported contact; RAD, laxity, venous congestion, fissure and twitching were observed up to 6 months after the alleged assault. Conclusions Anal findings are more common in children alleging anal abuse than in those presenting with physical abuse or neglect with no concern about sexual abuse. Multiple signs are rare in controls and support disclosed anal abuse. PMID:24884914

New release cell for NMR microimaging of tablets. Swelling and erosion of poly(ethylene oxide).

PubMed

Abrahmsén-Alami, Susanna; Körner, Anna; Nilsson, Ingvar; Larsson, Anette

2007-09-05

A small release cell, in the form of a rotating disc, has been constructed to fit into the MRI equipment. The present work show that both qualitative and quantitative information of the swelling and erosion behavior of hydrophilic extended release (ER) matrix tablets may be obtained using this release cell and non-invasive magnetic resonance imaging (MRI) studies at different time-points during matrix dissolution. The tablet size, core size and the gel layer thickness of ER matrix formulations based on poly(ethylene oxide) have been determined. The dimensional changes as a function of time were found to correspond well to observations made with texture analysis (TA) methodology. Most importantly, the results of the present study show that both the erosion (displacement of the gel-dissolution media interface) and the swelling (decrease of dry tablet core size) proceed with a faster rate in radial than in axial direction using the rotating disk set-up. This behavior was attributed to the higher shear forces experienced in the radial direction. The results also indicate that front synchronization (constant gel layer thickness) is associated with the formation of an almost constant polymer concentration profile through the gel layer at different time-points.

Communication: Light driven remote control of microgels' size in the presence of photosensitive surfactant: Complete phase diagram

NASA Astrophysics Data System (ADS)

Schimka, Selina; Gordievskaya, Yulia D.; Lomadze, Nino; Lehmann, Maren; von Klitzing, Regine; Rumyantsev, Artem M.; Kramarenko, Elena Yu.; Santer, Svetlana

2017-07-01

Here we report on a light triggered remote control of microgel size in the presence of photosensitive surfactant. The hydrophobic tail of the cationic surfactant contains azobenzene group that undergoes a reversible photo-isomerization reaction from a trans- to a cis-state accompanied by a change in the hydrophobicity of the surfactant. We have investigated light assisted behaviour and the complex formation of the microgels with azobenzene containing surfactant over the broad concentrational range starting far below and exceeding several times of the critical micelle concentration (CMC). At small surfactant concentration in solution (far below CMC), the surfactant in the trans-state accommodates within the microgel causing its compaction, while the cis-isomer desorbs out of microgel resulting in its swelling. The process of the microgel size change can be described as swelling on UV irradiation (trans-cis isomerization) and shrinking on irradiation with blue light (cis-trans isomerization). However, at the surfactant concentrations larger than CMC, the opposite behaviour is observed: the microgel swells on blue irradiation and shrinks during exposure to UV light. We explain this behaviour theoretically taking into account isomer dependent micellization of surfactant within the microgels.

Seasonal dimorphism in the horny bills of sparrows

EPA Science Inventory

Bill shape and size are often viewed as species-specific adaptations for feeding, but they sometimes vary between sexes, suggesting that sexual selection or inter-sexual competition may also be important. Hypotheses to explain sexual bill size dimorphism in birds avian bill size...

Interactions among mechanisms of sexual selection on male body size and head shape in a sexually dimorphic fly.

PubMed

Bonduriansky, Russell; Rowe, Locke

2003-09-01

Darwin envisaged male-male and male-female interactions as mutually supporting mechanisms of sexual selection, in which the best armed males were also the most attractive to females. Although this belief continues to predominate today, it has been challenged by sexual conflict theory, which suggests that divergence in the interests of males and females may result in conflicting sexual selection. This raises the empirical question of how multiple mechanisms of sexual selection interact to shape targeted traits. We investigated sexual selection on male morphology in the sexually dimorphic fly Prochyliza xanthostoma, using indices of male performance in male-male and male-female interactions in laboratory arenas to calculate gradients of direct, linear selection on male body size and an index of head elongation. In male-male combat, the first interaction with a new opponent selected for large body size but reduced head elongation, whereas multiple interactions with the same opponent favored large body size only. In male-female interactions, females preferred males with relatively elongated heads, but male performance of the precopulatory leap favored large body size and, possibly, reduced head elongation. In addition, the amount of sperm transferred (much of which is ingested by females) was an increasing function of both body size and head elongation. Thus, whereas both male-male and male-female interactions favored large male body size, male head shape appeared to be subject to conflicting sexual selection. We argue that conflicting sexual selection may be a common result of divergence in the interests of the sexes.

Correlation between investment in sexual traits and valve sexual dimorphism in Cyprideis species (Ostracoda)

PubMed Central

Hunt, Gene; Lockwood, Rowan; Swaddle, John P.; Horne, David J.

2017-01-01

Assessing the long-term macroevolutionary consequences of sexual selection has been hampered by the difficulty of studying this process in the fossil record. Cytheroid ostracodes offer an excellent system to explore sexual selection in the fossil record because their readily fossilized carapaces are sexually dimorphic. Specifically, males are relatively more elongate than females in this superfamily. This sexual shape difference is thought to arise so that males carapaces can accommodate their very large copulatory apparatus, which can account for up to one-third of body volume. Here we test this widely held explanation for sexual dimorphism in cytheroid ostracodes by correlating investment in male genitalia, a trait in which sexual selection is seen as the main evolutionary driver, with sexual dimorphism of carapace in the genus Cyprideis. We analyzed specimens collected in the field (C. salebrosa, USA; C. torosa, UK) and from collections of the National Museum of Natural History, Washington, DC (C. mexicana). We digitized valve outlines in lateral view to obtain measures of size (valve area) and shape (elongation, measured as length to height ratio), and obtained several dimensions from two components of the hemipenis: the muscular basal capsule, which functions as a sperm pump, and the section that includes the intromittent organ (terminal extension). In addition to the assessment of this primary sexual trait, we also quantified two dimensions of the male secondary sexual trait—where the transformed right walking leg functions as a clasping organ during mating. We also measured linear dimensions from four limbs as indicators of overall (soft-part) body size, and assessed allometry of the soft anatomy. We observed significant correlations in males between valve size, but not elongation, and distinct structural parts of the hemipenis, even after accounting for their shared correlation with overall body size. We also found weak but significant positive correlation between valve elongation and the degree of sexual dimorphism of the walking leg, but only in C. torosa. The correlation between the hemipenis parts, especially basal capsule size and male valve size dimorphism suggests that sexual selection on sperm size, quantity, and/or efficiency of transfer may drive sexual size dimorphism in these species, although we cannot exclude other aspects of sexual and natural selection. PMID:28678866

The role of grain size in He bubble formation: Implications for swelling resistance

DOE PAGES

El-Atwani, Osman; Nathaniel, II, James E.; Leff, Asher C.; ...

2016-12-07

Here, nanocrystalline metals are postulated as radiation resistant materials due to their high defect and particle (e.g. Helium) sink density. Here, the performance of nanocrystalline iron films is investigated in-situ in a transmission electron microscope (TEM) using He irradiation at 700 K. Automated crystal orientation mapping is used in concert with in-situ TEM to explore the role of grain orientation and grain boundary character on bubble density trends. Bubble density as a function of three key grain size regimes is demonstrated. While the overall trend revealed an increase in bubble density up to a saturation value, grains with areas rangingmore » from 3000 to 7500 nm 2 show a scattered distribution. An extrapolated swelling resistance based on bubble size and areal density indicated that grains with sizes less than 2000 nm 2 possess the greatest apparent resistance. Moreover, denuded zones are found to be independent of grain size, grain orientation, and grain boundary misorientation angle.« less

A dual-core double emulsion platform for osmolarity-controlled microreactor triggered by coalescence of encapsulated droplets.

PubMed

Guan, Xuewei; Hou, Likai; Ren, Yukun; Deng, Xiaokang; Lang, Qi; Jia, Yankai; Hu, Qingming; Tao, Ye; Liu, Jiangwei; Jiang, Hongyuan

2016-05-01

Droplet-based microfluidics has provided a means to generate multi-core double emulsions, which are versatile platforms for microreactors in materials science, synthetic biology, and chemical engineering. To provide new opportunities for double emulsion platforms, here, we report a glass capillary microfluidic approach to first fabricate osmolarity-responsive Water-in-Oil-in-Water (W/O/W) double emulsion containing two different inner droplets/cores and to then trigger the coalescence between the encapsulated droplets precisely. To achieve this, we independently control the swelling speed and size of each droplet in the dual-core double emulsion by controlling the osmotic pressure between the inner droplets and the collection solutions. When the inner two droplets in one W/O/W double emulsion swell to the same size and reach the instability of the oil film interface between the inner droplets, core-coalescence happens and this coalescence process can be controlled precisely. This microfluidic methodology enables the generation of highly monodisperse dual-core double emulsions and the osmolarity-controlled swelling behavior provides new stimuli to trigger the coalescence between the encapsulated droplets. Such swelling-caused core-coalescence behavior in dual-core double emulsion establishes a novel microreactor for nanoliter-scale reactions, which can protect reaction materials and products from being contaminated or released.

A dual-core double emulsion platform for osmolarity-controlled microreactor triggered by coalescence of encapsulated droplets

PubMed Central

Guan, Xuewei; Hou, Likai; Ren, Yukun; Deng, Xiaokang; Lang, Qi; Jia, Yankai; Hu, Qingming; Tao, Ye; Liu, Jiangwei; Jiang, Hongyuan

2016-01-01

Droplet-based microfluidics has provided a means to generate multi-core double emulsions, which are versatile platforms for microreactors in materials science, synthetic biology, and chemical engineering. To provide new opportunities for double emulsion platforms, here, we report a glass capillary microfluidic approach to first fabricate osmolarity-responsive Water-in-Oil-in-Water (W/O/W) double emulsion containing two different inner droplets/cores and to then trigger the coalescence between the encapsulated droplets precisely. To achieve this, we independently control the swelling speed and size of each droplet in the dual-core double emulsion by controlling the osmotic pressure between the inner droplets and the collection solutions. When the inner two droplets in one W/O/W double emulsion swell to the same size and reach the instability of the oil film interface between the inner droplets, core-coalescence happens and this coalescence process can be controlled precisely. This microfluidic methodology enables the generation of highly monodisperse dual-core double emulsions and the osmolarity-controlled swelling behavior provides new stimuli to trigger the coalescence between the encapsulated droplets. Such swelling-caused core-coalescence behavior in dual-core double emulsion establishes a novel microreactor for nanoliter-scale reactions, which can protect reaction materials and products from being contaminated or released. PMID:27279935

Molecular accessibility in solvent swelled coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kispert, L.D.

1991-08-01

Research continued on the determination of pore size and number distribution changes after swelling the coal samples with various solvents. A paper has just been submitted to the journal Fuel on the Low temperature Swelling of Argonne Premium Coal samples using solvents of varying polarity. The variation in the shape of the pore was followed as a function of temperature and swelling solvent polarity. This change in pore structure was attributed to break-up of the hydrogen bonding network in coal by polar solvents. The modification in pore shape from spherical to cylindrical was attributed to anisotropy in hydrogen bond densities.more » A copy of this paper has been attached to this report. Wojciech Sady has determine the structural changes in the pores that occur when APCS coal is dehydrated prior to swelling with polar solvents. These changes are different from those that occur in the absence of prior dehydration. He has also completed a study on the variation in the hydrogen bonding character of the pore wall as the coals are swelled with various polar solvents. A statistical analysis of the data is currently underway to determine important trends in his data. 9 refs.« less

Application of laboratory reflectance spectroscopy to target and map expansive soils: example of the western Loiret, France

NASA Astrophysics Data System (ADS)

Hohmann, Audrey; Dufréchou, Grégory; Grandjean, Gilles; Bourguignon, Anne

2014-05-01

Swelling soils contain clay minerals that change volume with water content and cause extensive and expensive damage on infrastructures. Based on spatial distribution of infrastructure damages and existing geological maps, the Bureau de Recherches Géologiques et Minières (BRGM, i.e. the French Geological Survey) published in 2010 a 1:50 000 swelling hazard map of France, indexing the territory to low, moderate, or high swelling risk. This study aims to use SWIR (1100-2500 nm) reflectance spectra of soils acquired under laboratory controlled conditions to estimate the swelling potential of soils and improve the swelling risk map of France. 332 samples were collected at the W of Orléans (France) in various geological formations and swelling risk areas. Comparisons of swelling potential of soil samples and swelling risk areas of the map show several inconsistent associations that confirm the necessity to redraw the actual swelling risk map of France. New swelling risk maps of the sampling area were produce from soil samples using three interpolation methods. Maps produce using kriging and Natural neighbour interpolation methods did not permit to show discrete lithological units, introduced unsupported swelling risk zones, and did not appear useful to refine swelling risk map of France. Voronoi polygon was also used to produce map where swelling potential estimated from each samples were extrapolated to a polygon and all polygons were thus supported by field information. From methods tested here, Voronoi polygon appears thus the most adapted method to produce expansive soils maps. However, size of polygon is highly dependent of the samples spacing and samples may not be representative of the entire polygon. More samples are thus needed to provide reliable map at the scale of the sampling area. Soils were also sampled along two sections with a sampling interval of ca. 260 m and ca. 50 m. Sample interval of 50 m appears more adapted for mapping of smallest lithological units. The presence of several samples close to themselves indicating the same swelling potential is a good indication of the presence of a zone with constant swelling potential. Combination of Voronoi method and sampling interval of ca. 50 m appear adapted to produce local swelling potential maps in areas where doubt remain or where infrastructure damages attributed to expansive soils are knew.

Light inhibits spore germination through phytochrome in Aspergillus nidulans.

PubMed

Röhrig, Julian; Kastner, Christian; Fischer, Reinhard

2013-05-01

Aspergillus nidulans responds to light in several aspects. The balance between sexual and asexual development as well as the amount of secondary metabolites produced is controlled by light. Here, we show that germination is largely delayed by blue (450 nm), red (700 nm), and far-red light (740 nm). The largest effect was observed with far-red light. Whereas 60 % of the conidia produced a germ tube after 20 h in the dark, less than 5 % of the conidia germinated under far-red light conditions. Because swelling of conidia was not affected, light appears to act at the stage of germ-tube formation. In the absence of nutrients, far-red light even inhibited swelling of conidia, whereas in the dark, conidia did swell and germinated after prolonged incubation. The blue-light signaling components, LreA (WC-1) and LreB (WC-2), and also the cryptochrome/photolyase CryA were not required for germination inhibition. However, in the phytochrome mutant, ∆fphA, the germination delay was released, but germination was delayed in the dark in comparison to wild type. This suggests a novel function of phytochrome as far-red light sensor and as activator of polarized growth in the dark.

Charge-regularized swelling kinetics of polyelectrolyte gels

NASA Astrophysics Data System (ADS)

Sen, Swati; Kundagrami, Arindam

The swelling kinetics of polyelectrolyte gels with fixed and variable degrees of ionization in salt-free solvent is studied by solving the constitutive equation of motion of the spatially and temporally varying displacement variable. Two methods for the swelling kinetics - the Bulk Modulus Method (BMM), which uses a linear stress-strain relationship (and, hence a bulk modulus), and the Stress Relaxation Method (SRM), which uses a phenomenological expression of osmotic stress, are explored to provide the spatio-temporal profiles for polymer density, osmotic stress, and degree of ionization, along with the time evolution of the gel size. Further, we obtain an analytical expression for the elastic modulus for linearized stress in the limit of small deformations. We match our theoretical profiles with the experiments of swelling of PNIPAM (uncharged) and Imidazolium-based (charged) minigels available in the literature. Ministry of Human Resource Development (MHRD), Government of India.

Erythrocyte swelling and membrane hole formation in hypotonic media as studied by conductometry.

PubMed

Pribush, A; Meyerstein, D; Hatskelzon, L; Kozlov, V; Levi, I; Meyerstein, N

2013-02-01

Hypoosmotic swelling of erythrocytes and the formation of membrane holes were studied by measuring the dc conductance (G). In accordance with the theoretical predictions, these processes are manifested by a decrease in G followed by its increase. Thus, unlike the conventional osmotic fragility test, the proposed methodological approach allows investigations of both the kinetics of swelling and the erythrocyte fragility. It is shown that the initial rate of swelling and the equilibrium size of the cells are affected by the tonicity of a hypotonic solution and the membrane rheological properties. Because the rupture of biological membranes is a stochastic process, a time-dependent increase in the conductance follows an integral distribution function of the membrane lifetime. The main conclusion which stems from reported results is that information about rheological properties of red blood cell (RBC) membranes and the resistivity of RBCs to a certain osmotic shock may be extracted from conductance signals.

Traumatic orbital CSF leak

PubMed Central

Borumandi, Farzad

2013-01-01

Compared to the cerebrospinalfluid (CSF) leak through the nose and ear, the orbital CSF leak is a rare and underreported condition following head trauma. We present the case of a 49-year-old woman with oedematous eyelid swelling and ecchymosis after a seemingly trivial fall onto the right orbit. Apart from the above, she was clinically unremarkable. The CT scan revealed a minimally displaced fracture of the orbital roof with no emphysema or intracranial bleeding. The fractured orbital roof in combination with the oedematous eyelid swelling raised the suspicion for orbital CSF leak. The MRI of the neurocranium demonstrated a small-sized CSF fistula extending from the anterior cranial fossa to the right orbit. The patient was treated conservatively and the lid swelling resolved completely after 5 days. Although rare, orbital CSF leak needs to be included in the differential diagnosis of periorbital swelling following orbital trauma. PMID:24323381

The Role of Breast Size and Areolar Pigmentation in Perceptions of Women's Sexual Attractiveness, Reproductive Health, Sexual Maturity, Maternal Nurturing Abilities, and Age.

PubMed

Dixson, Barnaby J; Duncan, Melanie; Dixson, Alan F

2015-08-01

Women's breast morphology is thought to have evolved via sexual selection as a signal of maturity, health, and fecundity. While research demonstrates that breast morphology is important in men's judgments of women's attractiveness, it remains to be determined how perceptions might differ when considering a larger suite of mate relevant attributes. Here, we tested how variation in breast size and areolar pigmentation affected perceptions of women's sexual attractiveness, reproductive health, sexual maturity, maternal nurturing abilities, and age. Participants (100 men; 100 women) rated images of female torsos modeled to vary in breast size (very small, small, medium, and large) and areolar pigmentation (light, medium, and dark) for each of the five attributes listed above. Sexual attractiveness ratings increased linearly with breast size, but large breasts were not judged to be significantly more attractive than medium-sized breasts. Small and medium-sized breasts were rated as most attractive if they included light or medium colored areolae, whereas large breasts were more attractive if they had medium or dark areolae. Ratings for perceived age, sexual maturity, and nurturing ability also increased with breast size. Darkening the areolae reduced ratings of the reproductive health of medium and small breasts, whereas it increased ratings for large breasts. There were no significant sex differences in ratings of any of the perceptual measures. These results demonstrate that breast size and areolar pigmentation interact to determine ratings for a suite of sociosexual attributes, each of which may be relevant to mate choice in men and intra-sexual competition in women.

Phylogeny suggests nondirectional and isometric evolution of sexual size dimorphism in argiopine spiders.

PubMed

Cheng, Ren-Chung; Kuntner, Matjaž

2014-10-01

Sexual dimorphism describes substantial differences between male and female phenotypes. In spiders, sexual dimorphism research almost exclusively focuses on size, and recent studies have recovered steady evolutionary size increases in females, and independent evolutionary size changes in males. Their discordance is due to negative allometric size patterns caused by different selection pressures on male and female sizes (converse Rensch's rule). Here, we investigated macroevolutionary patterns of sexual size dimorphism (SSD) in Argiopinae, a global lineage of orb-weaving spiders with varying degrees of SSD. We devised a Bayesian and maximum-likelihood molecular species-level phylogeny, and then used it to reconstruct sex-specific size evolution, to examine general hypotheses and different models of size evolution, to test for sexual size coevolution, and to examine allometric patterns of SSD. Our results, revealing ancestral moderate sizes and SSD, failed to reject the Brownian motion model, which suggests a nondirectional size evolution. Contrary to predictions, male and female sizes were phylogenetically correlated, and SSD evolution was isometric. We interpret these results to question the classical explanations of female-biased SSD via fecundity, gravity, and differential mortality. In argiopines, SSD evolution may be driven by these or additional selection mechanisms, but perhaps at different phylogenetic scales. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

[Idiopathic elephantiasis of the penis: a case report].

PubMed

Yamamoto, Keisuke; Matsuoka, Yasuhiro; Takao, Tetsuya; Tsujimur, Akira; Okuyama, Akihiko; Kubo, Tateki; Hosokawa, Kou; Kakuta, Yoichi; Yamaguchi, Seiji

2009-03-01

We report a case of idiopathic elephantiasis of penis. A 41-year-old man was refered to our hospital with a painful penile swelling and severe miction pain. He had no particular past or familial history, and had never been to tropical or semitropical region. Physical examination showed a prominent swelling and flection of his penis. Magnetic resonance imaging revealed a significant thickening of the penile skin and subcutaneous tissue. Due to the difficulty of voiding, an urethral catheter was placed. The penile skin biopsy showed no malignancy. Under the diagnosis of penile elephantiasis, the resection of abnormal penile skin and penile plasty with the split skin graft from his thigh was performed. Histopathological findings showed nonspecific inflammation. The skin graft was successfully adapted. He could urinate smoothly without pain after the urethral catheter was removed. There has been no recurrence 6 months after the operation. He recovered normal micturition and sexual function.

Selection for predation, not female fecundity, explains sexual size dimorphism in the orchid mantises.

PubMed

Svenson, Gavin J; Brannoch, Sydney K; Rodrigues, Henrique M; O'Hanlon, James C; Wieland, Frank

2016-12-01

Here we reconstruct the evolutionary shift towards floral simulation in orchid mantises and suggest female predatory selection as the likely driving force behind the development of extreme sexual size dimorphism. Through analysis of body size data and phylogenetic modelling of trait evolution, we recovered an ancestral shift towards sexual dimorphisms in both size and appearance in a lineage of flower-associated praying mantises. Sedentary female flower mantises dramatically increased in size prior to a transition from camouflaged, ambush predation to a floral simulation strategy, gaining access to, and visually attracting, a novel resource: large pollinating insects. Male flower mantises, however, remained small and mobile to facilitate mate-finding and reproductive success, consistent with ancestral male life strategy. Although moderate sexual size dimorphisms are common in many arthropod lineages, the predominant explanation is female size increase for increased fecundity. However, sex-dependent selective pressures acting outside of female fecundity have been suggested as mechanisms behind niche dimorphisms. Our hypothesised role of predatory selection acting on females to generate both extreme sexual size dimorphism coupled with niche dimorphism is novel among arthropods.

Selection for predation, not female fecundity, explains sexual size dimorphism in the orchid mantises

PubMed Central

Svenson, Gavin J.; Brannoch, Sydney K.; Rodrigues, Henrique M.; O’Hanlon, James C.; Wieland, Frank

2016-01-01

Here we reconstruct the evolutionary shift towards floral simulation in orchid mantises and suggest female predatory selection as the likely driving force behind the development of extreme sexual size dimorphism. Through analysis of body size data and phylogenetic modelling of trait evolution, we recovered an ancestral shift towards sexual dimorphisms in both size and appearance in a lineage of flower-associated praying mantises. Sedentary female flower mantises dramatically increased in size prior to a transition from camouflaged, ambush predation to a floral simulation strategy, gaining access to, and visually attracting, a novel resource: large pollinating insects. Male flower mantises, however, remained small and mobile to facilitate mate-finding and reproductive success, consistent with ancestral male life strategy. Although moderate sexual size dimorphisms are common in many arthropod lineages, the predominant explanation is female size increase for increased fecundity. However, sex-dependent selective pressures acting outside of female fecundity have been suggested as mechanisms behind niche dimorphisms. Our hypothesised role of predatory selection acting on females to generate both extreme sexual size dimorphism coupled with niche dimorphism is novel among arthropods. PMID:27905469

Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

PubMed

Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

2016-08-01

Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

Ornament Complexity Is Correlated with Sexual Selection: (A Comment on Raia et al., "Cope's Rule and the Universal Scaling Law of Ornament Complexity").

PubMed

Holman, Luke; Bro-Jørgensen, Jakob

2016-08-01

Raia et al. propose that the evolution of the shape and complexity of animal ornaments (e.g., deer antlers) can be explained by interspecific variation in body size and is not influenced by sexual selection. They claim to show that ornament complexity is related to body size by an 0.25-power law and argue that this finding precludes a role for sexual selection in the evolution of ornament complexity. However, their study does not test alternative hypotheses and mismeasures antler shape allometry by omitting much of the published data. We show that an index of sexual selection (sexual size dimorphism) is positively correlated with size-corrected antler complexity and that the allometric slope of complexity is substantially greater than 0.25, contra Raia et al. We conclude that sexual selection and physical constraints both affect the evolution of antler shape.

Recognition and Construction of Top, Bottom, and Versatile Orientations in Gay/Bisexual Men.

PubMed

Moskowitz, David A; Roloff, Michael E

2017-01-01

Research on gay and bisexual men's sexual position self-label (i.e., being a top, bottom, or versatile during anal sex) has revealed only independent snapshots of its development by focusing primarily on the influence of penis size. Moreover, the basic chronology of development of the sexual position self-label has barely been addressed. In response, we implemented a survey of 282 gay and bisexual men that measured demographics (including height and penis size), age of sexual recognitions, sexual position self-label, and attitudinal constructs suggested by previous literature as important (e.g., pleasure, control, anxieties, and gender typicality). Results suggested that men's sexual position self-label was learned over a 15-year timespan. Ages of first same-sex genital manipulation and first anal sex experiences were related to age at first self-labeling. With respect to predictors of labels, a multivariate path model was created. The model did not support the direct importance of penis size, but identified indirect paths that linked penis size to top/bottom identification (e.g., smaller penis sizes leading to topping-anxieties and thus, a bottom label). Finding bottoming to be pleasurable and the importance of sexual control dynamics were the only two direct predictors. The path model substantiated the reliance both bottoms and tops show towards seeking (or not seeking among tops) gender typical, sexually dominant partners. It also supported previous evidence regarding race; specifically, while race may activate differences in sexual behavioral dynamics, it is not a great predictor of the sexual position self-label. This study shows that sexual position self-labeling has enormous complexity and cannot be reduced down to penis size.

Penile and sexual rehabilitation in a patient with lymphedema of the penis.

PubMed

Pereira de Godoy, Jose Maria; de Fatima Guerreiro Godoy, Maria; Spessoto, Luis Cesar; Nestor Facio, Fernando

2013-01-01

The aim of this study is to report on penile rehabilitation in lymphedema of the penis with a new compression mechanism and the implantation of a penile prosthesis for sexual rehabilitation. The case of a 72-year-old patient with a history of edema of the penis for 6 years is reported. The patient reported that he had had periods of edema and redness and that the swelling had worsened over time. A clinical diagnosis of lymphedema of unknown etiology was made; the hypotheses were that the etiology was late congenital lymphedema of the penis or lymphedema aggravated by inflammation and/or infection. A new compression mechanism made using a cotton-polyester fabric (low elasticity and ribbed) was employed. The continued use of compression therapy led to almost complete reduction of the edema and the patient tried to return to be sexually active. A specific medication was used for erectile dysfunction; however, it resulted in no improvement and so a penile prosthesis was implanted. Copyright © 2013 S. Karger AG, Basel.

Can Foraging Ecology Drive the Evolution of Body Size in a Diving Endotherm?

PubMed Central

Cook, Timothée R.; Lescroël, Amélie; Cherel, Yves; Kato, Akiko; Bost, Charles-André

2013-01-01

Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes. PMID:23409169

Can foraging ecology drive the evolution of body size in a diving endotherm?

PubMed

Cook, Timothée R; Lescroël, Amélie; Cherel, Yves; Kato, Akiko; Bost, Charles-André

2013-01-01

Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes.

Analysis of Effective Interconnectivity of DegraPol-foams Designed for Negative Pressure Wound Therapy

PubMed Central

Milleret, Vincent; Bittermann, Anne Greet; Mayer, Dieter; Hall, Heike

2009-01-01

Many wounds heal slowly and are difficult to manage. Therefore Negative Pressure Wound Therapy (NPWT) was developed where polymer foams are applied and a defined negative pressure removes wound fluid, reduces bacterial burden and increases the formation of granulation tissue. Although NPWT is used successfully, its mechanisms are not well understood. In particular, different NPWT dressings were never compared. Here a poly-ester urethane Degrapol® (DP)-foam was produced and compared with commercially available dressings (polyurethane-based and polyvinyl-alcohol-based) in terms of apparent pore sizes, swelling and effective interconnectivity of foam pores. DP-foams contain relatively small interconnected pores; PU-foams showed large pore size and interconnectivity; whereas PVA-foams displayed heterogeneous and poorly interconnected pores. PVA-foams swelled by 40 %, whereas DP- and PU-foams remained almost without swelling. Effective interconnectivity was investigated by submitting fluorescent beads of 3, 20 and 45 μm diameter through the foams. DP- and PU-foams removed 70-90 % of all beads within 4 h, independent of the bead diameter or bead pre-adsorption with serum albumin. For PVA-foams albumin pre-adsorbed beads circulated longer, where 20 % of 3 μm and 10 % of 20 μm diameter beads circulated after 96 h. The studies indicate that efficient bead perfusion does not only depend on pore size and swelling capacity, but effective interconnectivity might also depend on chemical composition of the foam itself. In addition due to the efficient sieve-effect of the foams uptake of wound components in vivo might occur only for short time suggesting other mechanisms being decisive for success of NPWT.

Sexual size dimorphism predicts the frequency of sexual cannibalism within and among species of spiders.

PubMed

Wilder, Shawn M; Rypstra, Ann L

2008-09-01

Sexual cannibalism varies widely among spiders, but no general evolutionary hypothesis has emerged to explain its distribution across taxa. Sexual size dimorphism (SSD) also varies widely among spiders and could affect the vulnerability of males to cannibalistic attacks by females. We tested for a relationship between SSD and sexual cannibalism within and among species of spiders, using a broad taxonomic data set. For most species, cannibalism was more likely when males were much smaller than females. In addition, using phylogenetically controlled and uncontrolled analyses, there was a strong positive relationship between average SSD of a species and the frequency of sexual cannibalism. This is the first evidence that the degree of size difference between males and females is related to the phylogenetic distribution of sexual cannibalism among a broad range of spiders.

Scaling behavior of knotted random polygons and self-avoiding polygons: Topological swelling with enhanced exponent.

PubMed

Uehara, Erica; Deguchi, Tetsuo

2017-12-07

We show that the average size of self-avoiding polygons (SAPs) with a fixed knot is much larger than that of no topological constraint if the excluded volume is small and the number of segments is large. We call it topological swelling. We argue an "enhancement" of the scaling exponent for random polygons with a fixed knot. We study them systematically through SAP consisting of hard cylindrical segments with various different values of the radius of segments. Here we mean by the average size the mean-square radius of gyration. Furthermore, we show numerically that the topological balance length of a composite knot is given by the sum of those of all constituent prime knots. Here we define the topological balance length of a knot by such a number of segments that topological entropic repulsions are balanced with the knot complexity in the average size. The additivity suggests the local knot picture.

Scaling behavior of knotted random polygons and self-avoiding polygons: Topological swelling with enhanced exponent

NASA Astrophysics Data System (ADS)

Uehara, Erica; Deguchi, Tetsuo

2017-12-01

We show that the average size of self-avoiding polygons (SAPs) with a fixed knot is much larger than that of no topological constraint if the excluded volume is small and the number of segments is large. We call it topological swelling. We argue an "enhancement" of the scaling exponent for random polygons with a fixed knot. We study them systematically through SAP consisting of hard cylindrical segments with various different values of the radius of segments. Here we mean by the average size the mean-square radius of gyration. Furthermore, we show numerically that the topological balance length of a composite knot is given by the sum of those of all constituent prime knots. Here we define the topological balance length of a knot by such a number of segments that topological entropic repulsions are balanced with the knot complexity in the average size. The additivity suggests the local knot picture.

Brain size evolution in pipefishes and seahorses: the role of feeding ecology, life history and sexual selection.

PubMed

Tsuboi, M; Lim, A C O; Ooi, B L; Yip, M Y; Chong, V C; Ahnesjö, I; Kolm, N

2017-01-01

Brain size varies greatly at all taxonomic levels. Feeding ecology, life history and sexual selection have been proposed as key components in generating contemporary diversity in brain size across vertebrates. Analyses of brain size evolution have, however, been limited to lineages where males predominantly compete for mating and females choose mates. Here, we present the first original data set of brain sizes in pipefishes and seahorses (Syngnathidae) a group in which intense female mating competition occurs in many species. After controlling for the effect of shared ancestry and overall body size, brain size was positively correlated with relative snout length. Moreover, we found that females, on average, had 4.3% heavier brains than males and that polyandrous species demonstrated more pronounced (11.7%) female-biased brain size dimorphism. Our results suggest that adaptations for feeding on mobile prey items and sexual selection in females are important factors in brain size evolution of pipefishes and seahorses. Most importantly, our study supports the idea that sexual selection plays a major role in brain size evolution, regardless of on which sex sexual selection acts stronger. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Modeling the arrangement of particles in natural swelling-clay porous media using three-dimensional packing of elliptic disks

NASA Astrophysics Data System (ADS)

Ferrage, Eric; Hubert, Fabien; Tertre, Emmanuel; Delville, Alfred; Michot, Laurent J.; Levitz, Pierre

2015-06-01

Swelling clay minerals play a key role in the control of water and pollutant migration in natural media such as soils. Moreover, swelling clay particles' orientational properties in porous media have significant implications for the directional dependence of fluid transfer. Herein we investigate the ability to mimic the organization of particles in natural swelling-clay porous media using a three-dimensional sequential particle deposition procedure [D. Coelho, J.-F. Thovert, and P. M. Adler, Phys. Rev. E 55, 1959 (1997), 10.1103/PhysRevE.55.1959]. The algorithm considered is first used to simulate disk packings. Porosities of disk packings fall onto a single master curve when plotted against the orientational scalar order parameter value. This relation is used to validate the algorithm used in comparison with existing ones. The ellipticity degree of the particles is shown to have a negligible effect on the packing porosity for ratios ℓa/ℓb less than 1.5, whereas a significant increase in porosity is obtained for higher values. The effect of the distribution of the geometrical parameters (size, aspect ratio, and ellipticity degree) of particles on the final packing properties is also investigated. Finally, the algorithm is used to simulate particle packings for three size fractions of natural swelling-clay mineral powders. Calculated data regarding the distribution of the geometrical parameters and orientation of particles in porous media are successfully compared with experimental data obtained for the same samples. The results indicate that the obtained virtual porous media can be considered representative of natural samples and can be used to extract properties difficult to obtain experimentally, such as the anisotropic features of pore and solid phases in a system.

Risky Sexual Behavior and Substance Use among Adolescents: A Meta-analysis

PubMed Central

Ritchwood, Tiarney D.; Ford, Haley; DeCoster, Jamie; Sutton, Marnie; Lochman, John E.

2015-01-01

This study presents the results of a meta-analysis of the association between substance use and risky sexual behavior among adolescents. 87 studies fit the inclusion criteria, containing a total of 104 independent effect sizes that incorporated more than 120,000 participants. The overall effect size for the relationship between substance use and risky sexual behavior was in the small to moderate range (r = .22, CI = .18, .26). Further analyses indicated that the effect sizes did not substantially vary across the type of substance use, but did substantially vary across the type of risky sexual behavior being assessed. Specifically, mean effect sizes were smallest for studies examining unprotected sex (r = .15, CI = .10, .20), followed by studies examining number of sexual partners (r = .25, CI = .21, .30), those examining composite measures of risky sexual behavior (r = .38, CI = .27, .48), and those examining sex with an intravenous drug user (r = .53, CI = .45, .60). Furthermore, our results revealed that the relationship between drug use and risky sexual behavior is moderated by several variables, including sex, ethnicity, sexuality, age, sample type, and level of measurement. Implications and future directions are discussed. PMID:25825550

Sexual selection accounts for the geographic reversal of sexual size dimorphism in the dung fly, sepsis punctum (Diptera: Sepsidae).

PubMed

Puniamoorthy, Nalini; Schäfer, Martin A; Blanckenhorn, Wolf U

2012-07-01

Sexual size dimorphism (SSD) varies widely across and within species. The differential equilibrium model of SSD explains dimorphism as the evolutionary outcome of consistent differences in natural and sexual selection between the sexes. Here, we comprehensively examine a unique cross-continental reversal in SSD in the dung fly, Sepsis punctum. Using common garden laboratory experiments, we establish that SSD is male-biased in Europe and female-biased in North America. When estimating sexual (pairing success) and fecundity selection (clutch size of female partner) on males under three operational sex ratios (OSRs), we find that the intensity of sexual selection is significantly stronger in European versus North American populations, increasing with male body size and OSR in the former only. Fecundity selection on female body size also increases strongly with egg number and weakly with egg volume, however, equally on both continents. Finally, viability selection on body size in terms of intrinsic (physiological) adult life span in the laboratory is overall nil and does not vary significantly across all seven populations. Although it is impossible to prove causality, our results confirm the differential equilibrium model of SSD in that differences in sexual selection intensity account for the reversal in SSD in European versus North American populations, presumably mediating the ongoing speciation process in S. punctum. © 2012 The Author(s).

Cross-sex genetic correlation does not extend to sexual size dimorphism in spiders

NASA Astrophysics Data System (ADS)

Turk, Eva; Kuntner, Matjaž; Kralj-Fišer, Simona

2018-02-01

Males and females are often subjected to different selection pressures for homologous traits, resulting in sex-specific optima. Because organismal attributes usually share their genetic architectures, sex-specific selection may lead to intralocus sexual conflict. Evolution of sexual dimorphism may resolve this conflict, depending on the degree of cross-sex genetic correlation ( r MF) and the strength of sex-specific selection. In theory, high r MF implies that sexes largely share the genetic base for a given trait and are consequently sexually monomorphic, while low r MF indicates a sex-specific genetic base and sexual dimorphism. Here, we broadly test this hypothesis on three spider species with varying degrees of female-biased sexual size dimorphism, Larinioides sclopetarius (sexual dimorphism index, SDI = 0.85), Nuctenea umbratica (SDI = 0.60), and Zygiella x-notata (SDI = 0.46). We assess r MF via same-sex and opposite-sex heritability estimates. We find moderate body mass heritability but no obvious patterns in sex-specific heritability. Against the prediction, the degree of sexual size dimorphism is unrelated to the relative strength of same-sex versus opposite-sex heritability. Our results do not support the hypothesis that sexual size dimorphism is negatively associated with r MF. We conclude that sex-specific genetic architecture may not be necessary for the evolution of a sexually dimorphic trait.

Sexual selection and the risk of extinction in birds.

PubMed Central

Morrow, Edward H; Pitcher, Trevor E

2003-01-01

The relationship between sexual selection and extinction risk has rarely been investigated. This is unfortunate because extinction plays a key role in determining the patterns of species richness seen in extant clades, which form the basis of comparative studies into the role that sexual selection may play in promoting speciation. We investigate the extent to which the perceived risk of extinction relates to four different estimates of sexual selection in 1030 species of birds. We find no evidence that the number of threatened species is distributed unevenly according to a social mating system, and neither of our two measures of pre-mating sexual selection (sexual dimorphism and dichromatism) was related to extinction risk, after controlling for phylogenetic inertia. However, threatened species apparently experience more intense post-mating sexual selection, measured as testis size, than non-threatened species. These results persisted after including body size as a covariate in the analysis, and became even stronger after controlling for clutch size (two known correlates of extinction risk). Sexual selection may therefore be a double-edged process-promoting speciation on one hand but promoting extinction on the other. Furthermore, we suggest that it is post-mating sexual selection, in particular, that is responsible for the negative effect of sexual selection on clade size. Why this might be is unclear, but the mean population fitness of species with high intensities of post-mating sexual selection may be especially low if costs associated with multiple mating are high or if the selection load imposed by post-mating selection is higher relative to that of pre-mating sexual selection. PMID:12964981

Sexual selection on male size drives the evolution of male-biased sexual size dimorphism via the prolongation of male development.

PubMed

Rohner, Patrick T; Blanckenhorn, Wolf U; Puniamoorthy, Nalini

2016-06-01

Sexual size dimorphism (SSD) arises when the net effects of natural and sexual selection on body size differ between the sexes. Quantitative SSD variation between taxa is common, but directional intraspecific SSD reversals are rare. We combined micro- and macroevolutionary approaches to study geographic SSD variation in closely related black scavenger flies. Common garden experiments revealed stark intra- and interspecific variation: Sepsis biflexuosa is monomorphic across the Holarctic, while S. cynipsea (only in Europe) consistently exhibits female-biased SSD. Interestingly, S. neocynipsea displays contrasting SSD in Europe (females larger) and North America (males larger), a pattern opposite to the geographic reversal in SSD of S. punctum documented in a previous study. In accordance with the differential equilibrium model for the evolution of SSD, the intensity of sexual selection on male size varied between continents (weaker in Europe), whereas fecundity selection on female body size did not. Subsequent comparative analyses of 49 taxa documented at least six independent origins of male-biased SSD in Sepsidae, which is likely caused by sexual selection on male size and mediated by bimaturism. Therefore, reversals in SSD and the associated changes in larval development might be much more common and rapid and less constrained than currently assumed. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

EVOLUTION, PHYLOGENY, SEXUAL DIMORPHISM AND MATING SYSTEM IN THE GRACKLES (QUISCALUS SPP.: ICTERINAE).

PubMed

Björklund, Mats

1991-05-01

According to theory, two consequences of sexual selection are sexual dimorphism in size and secondary sexual characteristics, due to either intra- or intersexual selection. In this paper I suggest three criteria for the test of an evolutionary hypothesis involving quantitative morphological characters. First, the postulated change must be shown to have occurred in evolutionary time. Second, this change must be positively correlated with a change in the proposed selective agent. Third, given two taxa with different degrees of sexual size dimorphism and different mating system, the possible influence of drift must be rejected. If the hypothesis is not rejected by these three criteria, then we still have no proof of causality, but we can at least be more confident about its plausibility. This is applied to the particular hypothesis that sexual dimorphism in the Boat-tailed and Great-tailed grackles (Quiscalus spp; Icterinae; Aves) is caused by the highly polygynous mating system in these species. In relation to an outgroup, both species have increased disproportionately in male tarsus and tail size, creating an increased sexual dimorphism. This has cooccurred with the evolution of their particular mating system. However, the variance among species in male tarsus size can be accounted for by drift, and need not be a result of selection for increased size. In contrast, the variance among species in male tail size was much larger than expected under a null model of drift, indicating directional selection for long tails. The variance in female tail size was not larger than expected by drift, whereas the variance in female tarsus size was in fact lower than expected by drift, indicating stabilizing selection. The data are consistent with the hypothesis with regard to tail size, but not with regard to body size. © 1991 The Society for the Study of Evolution.

Evolution of sexual dimorphism and Rensch’s rule in the beetle genus Limnebius (Hydraenidae): is sexual selection opportunistic?

PubMed Central

Rudoy, Andrey

2017-01-01

Sexual size dimorphism (SSD) is widespread among animals, with larger females usually attributed to an optimization of resources in reproduction and larger males to sexual selection. A general pattern in the evolution of SSD is Rensch’s rule, which states that SSD increases with body size in species with larger males but decreases when females are larger. We studied the evolution of SSD in the genus Limnebius (Coleoptera, Hydraenidae), measuring SSD and male genital size and complexity of ca. 80% of its 150 species and reconstructing its evolution in a molecular phylogeny with 71 species. We found strong support for a higher evolutionary lability of male body size, which had an overall positive allometry with respect to females and higher evolutionary rates measured over the individual branches of the phylogeny. Increases in SSD were associated to increases in body size, but there were some exceptions with an increase associated to changes in only one sex. Secondary sexual characters (SSC) in the external morphology of males appeared several times independently, generally on species that had already increased their size. There was an overall significant correlation between SSD, male body size and male genital size and complexity, although some lineages with complex genitalia had low SSD, and some small species with complex genitalia had no SSD. Our results suggest that the origin of the higher evolutionary variance of male body size may be due to lack of constraints rather than to sexual selection, that may start to act in species with already larger males due to random variation. PMID:28286715

Evolution of sexual dimorphism and Rensch's rule in the beetle genus Limnebius (Hydraenidae): is sexual selection opportunistic?

PubMed

Rudoy, Andrey; Ribera, Ignacio

2017-01-01

Sexual size dimorphism (SSD) is widespread among animals, with larger females usually attributed to an optimization of resources in reproduction and larger males to sexual selection. A general pattern in the evolution of SSD is Rensch's rule, which states that SSD increases with body size in species with larger males but decreases when females are larger. We studied the evolution of SSD in the genus Limnebius (Coleoptera, Hydraenidae), measuring SSD and male genital size and complexity of ca. 80% of its 150 species and reconstructing its evolution in a molecular phylogeny with 71 species. We found strong support for a higher evolutionary lability of male body size, which had an overall positive allometry with respect to females and higher evolutionary rates measured over the individual branches of the phylogeny. Increases in SSD were associated to increases in body size, but there were some exceptions with an increase associated to changes in only one sex. Secondary sexual characters (SSC) in the external morphology of males appeared several times independently, generally on species that had already increased their size. There was an overall significant correlation between SSD, male body size and male genital size and complexity, although some lineages with complex genitalia had low SSD, and some small species with complex genitalia had no SSD. Our results suggest that the origin of the higher evolutionary variance of male body size may be due to lack of constraints rather than to sexual selection, that may start to act in species with already larger males due to random variation.

Sexual variation in assimilation efficiency: its link to phenotype and potential role in sexual dimorphism.

PubMed

Stahlschmidt, Zachary R; Davis, Jon R; Denardo, Dale F

2011-04-01

Sex-specific variation in morphology (sexual dimorphism) is a prevalent phenomenon among animals, and both dietary intake and resource allocation strategies influence sexually dimorphic traits (e.g., body size or composition). However, we investigated whether assimilation efficiency (AE), an intermediate step between dietary intake and allocation, can also vary between the sexes. Specifically, we tested whether sex-based differences in AE can explain variation in phenotypic traits. We measured morphometric characteristics (i.e., body length, mass, condition, and musculature) and AE of total energy, crude protein, and crude fat in post-reproductive adult Children's pythons (which exhibit a limited female-biased sexual size dimorphism) fed both low and high dietary intakes. Meal size was negatively related to AE of energy. Notably, male snakes absorbed crude protein more efficiently and increased epaxial (dorsal) musculature faster than females, which demonstrates a link between AE and phenotype. However, females grew in body length faster but did not absorb any nutrient more efficiently than males. Although our results do not provide a direct link between AE and sexual size dimorphism, they demonstrate that sexual variation in nutrient absorption exists and can contribute to other types of sex-based differences in phenotype (i.e., sexual dimorphism in growth of musculature). Hence, testing the broader applicability of AE's role in sexually dimorphic traits among other species is warranted.

Preparation and swelling inhibition of cation glucoside to montmorillonite

NASA Astrophysics Data System (ADS)

Song, Shaofu; Liu, Jurong; Guo, Gang; Huang, Lei; Qu, Chentun; Li, Bianqin; Chen, Gang

2017-06-01

In this work, a cation glucoside (CG) was synthesized with glucose and glycidyl trimethyl ammonium chloride (GTA) and used as montmorillonite (MMT) swelling inhibiter. The inhibition of CG was investigated by MMT linear expansion test and mud ball immersing test. The results showed that the CG has a good inhibition to the hydration swelling and dispersion of MMT. Under the same condition, the linear expansion rate of MMT in CG solution is much lower that of methylglucoside and the hydration expansion degree of the mud ball in the CG solution was significantly inhibited. The characterizations of physic-chemical properties of particle, analysized by thermogravimetric analysis and scanning electron microscopy, revealed that CG play great role to prevent water from absorb and keep MMT in large particle size.

A Process to Reduce DC Ingot Butt Curl and Swell

NASA Astrophysics Data System (ADS)

Yu, Ho

1980-11-01

A simple and effective process to reduce DC ingot butt curl and swell has been developed in the Ingot Casting Division of Alcoa Technical Center.1 In the process, carbon dioxide gas is dissolved under high pressure into the ingot cooling water upstream of the mold during the first several inches of the ingot cast. As the cooling water exits from the mold, the dissolved gas evolves as micron-size bubbles, forming a temporary effective insulation layer on the ingot surface. This reduces thermal stress in the ingot butt. An insulation pad covering about 60% of the bottom block is used in conjunction with the carbon dioxide injection when maximum butt swell reduction is desired. The process, implemented in four Alcoa ingot plants, has proven extremely successful.

Male group size, female distribution and changes in sexual segregation by Roosevelt elk

PubMed Central

Peterson, Leah M.

2017-01-01

Sexual segregation, or the differential use of space by males and females, is hypothesized to be a function of body size dimorphism. Sexual segregation can also manifest at small (social segregation) and large (habitat segregation) spatial scales for a variety of reasons. Furthermore, the connection between small- and large-scale sexual segregation has rarely been addressed. We studied a population of Roosevelt elk (Cervus elaphus roosevelti) across 21 years in north coastal California, USA, to assess small- and large-scale sexual segregation in winter. We hypothesized that male group size would associate with small-scale segregation and that a change in female distribution would associate with large-scale segregation. Variation in forage biomass might also be coupled to small and large-scale sexual segregation. Our findings were consistent with male group size associating with small-scale segregation and a change in female distribution associating with large-scale segregation. Females appeared to avoid large groups comprised of socially dominant males. Males appeared to occupy a habitat vacated by females because of a wider forage niche, greater tolerance to lethal risks, and, perhaps, to reduce encounters with other elk. Sexual segregation at both spatial scales was a poor predictor of forage biomass. Size dimorphism was coupled to change in sexual segregation at small and large spatial scales. Small scale segregation can seemingly manifest when all forage habitat is occupied by females and large scale segregation might happen when some forage habitat is not occupied by females. PMID:29121076

Swelling behaviour of Early Jurassic shales when exposed to water vapour

NASA Astrophysics Data System (ADS)

Houben, Maartje; Barnhoorn, Auke; Peach, Colin; Drury, Martyn

2017-04-01

The presence of water in mudrocks has a largely negative impact on production of gas, due to the fact that water causes swelling of the rock. Removing the water from the mudrock on the other hand could potentially shrink the rock and increase the matrix permeability. Investigation of the swelling/shrinkage behaviour of the rock during exposure to water vapour is of key importance in designing and optimizing unconventional production strategies. We have used outcrop samples of the Whitby Mudstone and the Posidonia shale [1], potential unconventional sources for gas in North-western Europe, to measure the swelling and shrinkage behaviour. Subsamples, 1 mm cubes, were prepared by the Glass Workshop at Utrecht University using a high precision digitally controlled diamond wafering saw cooled by air. The mm cubes were then exposed to atmospheres with different relative humidities either in an Environmental Scanning Electron Microscope (ESEM) or in a 3D dilatometer. So that the sample responses to exposure of water vapour could be measured. Parallel to the bedding we found a swelling strain between 0.5 and 1.5 %, perpendicular to the bedding though swelling strain varied between 1 and 3.5%. Volumetric swelling strain varied between 1 and 2% at a maximum relative humidity of 95%. Volumetric swelling strains measured in the Early Toarcian Shales are similar to the ones found in coal [2], where the results suggest that it might be possible to increase permeability in the reservoir by decreasing the in-situ water activity due to shrinkage of the matrix. [1] M.E. Houben, A. Barnhoorn, L. Wasch, J. Trabucho-Alexandre, C. J. Peach, M.R. Drury (2016). Microstructures of Early Jurassic (Toarcian) shales of Northern Europe, International Journal of Coal Geology, 165, 76-89. [2] Jinfeng Liu, Colin J. Peach, Christopher J. Spiers (2016). Anisotropic swelling behaviour of coal matrix cubes exposed to water vapour: Effects of relative humidity and sample size, International Journal of Coal Geology, 167, 119-135.

Oral insulin delivery using P(MAA-g-EG) hydrogels: effects of network morphology on insulin delivery characteristics.

PubMed

Nakamura, Koji; Murray, Robert J; Joseph, Jeffrey I; Peppas, Nicholas A; Morishita, Mariko; Lowman, Anthony M

2004-03-24

Hydrogels of poly(methacrylic acid-g-ethylene glycol) were prepared using different reaction water contents in order to vary the network mesh size, swelling behavior and insulin loading/release kinetics. Gels prepared with greater reaction solvent contents swelled to a greater degree and had a larger network mesh size. All of the hydrogels were able to incorporate insulin and protected it from release in acidic media. At higher pH (7.4), the release rates increased with reaction solvent content. Using a closed loop animal model, all of the insulin loaded formulations produced significant insulin absorption in the upper small intestine combined with hypoglycemic effects. In these studies, bioavailabilities ranged from 4.6% to 7.2% and were dependent on reaction solvent content.

Seminal characteristics and sexual behavior in men of different age groups: is there an aging effect?

PubMed

Zavos, Panayiotis M; Kaskar, Khalied; Correa, Juan R; Sikka, Suresh C

2006-05-01

To assess the seminal characteristics as well as the sexual behavior of men of various age groups to establish the presence of an aging effect on those characteristics. Semen samples were collected from men (n = 792) undergoing in vitro fertilization or intrauterine insemination in cases of female factor infertility only. Samples were collected using a seminal collection device at intercourse and evaluated manually according to World Health Organization (WHO) standards. Men were divided into four groups according to their ages: (i) 20-30, (ii) 31-40, (iii) 41-50 and (iv) 51-60 years, and their seminal characteristics and responses to a sexual behavior questionnaire were compared. The data showed statistically significant differences in the seminal characteristics tested, most notably in the sperm concentration, motility, grade of motility, hypo-osmotic swelling and normal sperm morphology. Furthermore, the decline in normal sperm morphology with age was more pronounced when using strict criteria rather than WHO standards. There were also differences in total sperm count, total motile sperm and total functional sperm fraction (assessed by both WHO and strict criteria). Significant differences were also observed in the sexual behavior patterns in older men in terms of the number of years they have been trying to conceive, sexual frequency and sexual satisfaction. The data clearly illustrate an aging effect on semen characteristics and sexual behavior in men as they age. It is suggested that the aging effect be taken into consideration when proposing normal standard values for semen characteristics in routine semen analysis as outlined by WHO standards.

Towards the determination of deformation rates - pinch-and-swell structures as a natural and simulated paleo-strain rate gage

NASA Astrophysics Data System (ADS)

Peters, Max; Poulet, Thomas; Karrech, Ali; Regenauer-Lieb, Klaus; Herwegh, Marco

2014-05-01

Layered rocks deformed under viscous deformation conditions frequently show boudinage, a phenomenon that results from differences in effective viscosity between the involved layers. In the case of continuous necking of a mechanically stiffer layer embedded in a weaker matrix, symmetric boudins are interpreted as the result of dominant visco-plastic deformation (Goscombe et al., 2004). However, information on the physical conditions, material properties and deformation processes are yet unknown. Natural samples deformed under low-grade (T<350°C) metamorphic conditions were studied in detail in the Dent de Morcles and Doldenhorn nappes of the Helvetic Alps in order to accurately simulate their deformation styles by numerical models. In these samples, monomineralic calcite (Cc) veins were repeatedly boudinaged on cm- to µm-scale. Remnants of incompletely recrystallized original vein Cc grains in the swells indicate a sequence of deformation twinning, followed by progressive dynamic recrystallization along former twin planes up to complete recrystallization in the pinches (Schmalholz and Maeder, 2012). This sequence suggests dislocation creep to be active as important deformation mechanism. In contrast to the pinch-and-swell structures, the grain size of the Cc in the surrounding matrix is much finer-grained due to pinning by secondary particles, forcing the matrix to deform under viscous granular creep, i.e. by diffusion accommodated grain boundary sliding. The deformation processes observed in the natural samples were incorporated into a numerical model in order to evaluate the rheology of both layer and matrix, using an extension to a user material subroutine (Karrech et al., 2011a) for the finite element solver ABAQUS. We implemented thermo-mechanical coupling allowing elastic, viscous and plastic deformation of Cc (Herwegh et al., in press). We simulate a pure-shear box using finite elements, each representing a grain size distribution, which undergo layer-parallel extension. The box is built up by 3 layers, consisting of a central layer of coarse-grained populations, surrounded by finer-grained populations on bottom and top. The rheology evolves from transient stages (elasticity and strain hardening) to composite viscous flow (GSI & GSS) with increasing shear strain. The small grain sizes in top and bottom layers are strain-invariant and limited in their growth (comparable to Zener pinning) forcing the matrix to deform by exclusively by GSS creep. In contrast, the initially coarse grain sizes of the central layer are allowed to adapt to the physical deformation conditions by either grain growth or grain size reduction following the Paleowattmeter of Austin and Evans (2007) combined with the thermodynamic approach of Regenauer-Lieb and Yuen (2004). Depending on the dissipated energy, grain sizes in these domains vary substantially in space and time. While low strain rates (low stresses) in the swells favor grain growth and GSI dominated deformation, high strain rates in the pinches provoke dramatic grain size reduction with an increasing contribution of GSS as a function of decreasing grain size. The development of symmetric necks observed in nature thus seems to coincide with the transition from dislocation to diffusion creep dominated flow with continuous grain size reduction and growth from swell to neck at relatively high extensional strains. REFERENCES Austin, N. and Evans, B. (2007). Paleowattmeters: A scaling relation for dynamically recrystallized grain size. Geology, 35. Goscombe, B.D., Passchier, C.W. and Hand, M. (2004). Boudinage classification: End-member boudin types and modified boudin structures, Journal of Structural Geology, 26. Herwegh, M., Poulet, T., Karrech, A. and Regenauer-Lieb, K. (in press). From transient to steady state deformation and grain size: A thermodynamic approach using elasto-visco-plastic numerical modeling. Journal of Geophysical Research. Karrech, A., Regenauer-Lieb, K. and Poulet, T. (2011a). A Damaged visco-plasticity model for pressure and temperature sensitive geomaterials. Journal of Engineering Science 49. Regenauer-Lieb, K. and Yuen, D. (2004). Positive feedback of interacting ductile faults from coupling of equation of state, rheology and thermal-mechanics. Physics of the Earth and Planetary Interiors, 142. Schmalholz, S.M. and Maeder, X. (2012). Pinch-and-swell structure and shear zones in viscoplastic layers. Journal of Structural Geology, 34.

Laser Doppler imaging of genital blood flow: a direct measure of female sexual arousal.

PubMed

Waxman, Samantha E; Pukall, Caroline F

2009-08-01

Female sexual arousal is a challenging construct to measure, partly because of the subtle nature of its indicators, vaginal lubrication and genital swelling. As a result, many instruments have been used in an attempt to accurately measure it; however, problems are associated with each. Furthermore, the relationship between subjective and physiological indicators of arousal appears to be influenced by the instrument used to measure physiological arousal. Specifically, instruments measuring physiological arousal internally yield lower correlations between measures of physiological and subjective arousal than instruments examining the external genitals. Laser Doppler imaging (LDI) is a direct measure of external genital blood flow. The purpose of this study was to investigate the usefulness of LDI for measuring genital blood flow in women in response to erotic visual stimuli, and to explore the relationship between physiological and subjective sexual arousal. Sixty-five participants watched three 15-minute films during LDI scanning. Two nature films (measuring acclimatization and baseline blood flow levels) and one randomly assigned experimental film (erotic, anxiety, humor, or neutral) were used. Participants rated their level of subjective arousal following the third film. Results indicated a significant effect of film condition on genital blood flow, P < 0.001, with the erotic condition differing significantly from the other three conditions. In terms of the relationship between physiological and subjective sexual arousal, physiological arousal was significantly predicted by subjective ratings of sexual arousal (P < 0.001). LDI appears to be able to differentiate blood flow during erotic and nonerotic conditions. In addition, physiological sexual arousal was significantly predicted by women's reported subjective sexual arousal. These findings suggest that LDI is a useful instrument for measuring female sexual arousal, and that women may be more aware of their level of physiological arousal than previously assumed.

Stable and pH-responsive core-shell nanoparticles based on HEC and PMAA networks via template copolymerization

NASA Astrophysics Data System (ADS)

Zhang, Y.; Jin, Q.; Chen, Y.; Zhao, J.

2011-10-01

Taking advantage of the specific hydrogen bonding interactions, stable and pH-responsive core-shell nanoparticles based on hydroxyethyl cellulose (HEC) and polymethacrylic acid (PMAA) networks, with a < D h > size ranging from 190 to 250 nm, can be efficiently prepared via facile one-step co-polymerization of methacrylic acid (MAA) and N, N'-methylenebisacrylamide (MBA) on HEC template in water. Using dynamic light scattering, electrophoretic light scattering, fluorescence spectrometry, thermo-gravimetric analysis, TEM, and AFM observations, the influence of crosslinker MBA as well as the reaction parameters were studied. The results show that after the introduction of crosslinker MBA, the nanoparticles became less compact; their size exhibited a smaller pH sensitivity, and their stability against pH value was improved greatly. Furthermore, the size, structure, and pH response of the nanoparticles can be adjusted via varying the reaction parameters: nanoparticles of smaller size, more compact structure, and higher swelling capacity were produced as pH value of the reaction medium increased or the HEC/MAA ratio decreased; while nanoparticles of smaller size, less compact structure and smaller swelling capacity were produced as the total feeding concentration increased.

Sexual selection and the rodent baculum: an intraspecific study in the house mouse (Mus musculus domesticus).

PubMed

Ramm, Steven A; Khoo, Lin; Stockley, Paula

2010-01-01

The rapid divergence of genitalia is a pervasive trend in animal evolution, thought to be due to the action of sexual selection. To test predictions from the sexual selection hypothesis, we here report data on the allometry, variation, plasticity and condition dependence of baculum morphology in the house mouse (Mus musculus domesticus). We find that that baculum size: (a) exhibits no consistent pattern of allometric scaling (baculum size being in most cases unrelated to body size), (b) exhibits low to moderate levels of phenotypic variation, (c) does not exhibit phenotypic plasticity in response to differences in perceived levels of sexual competition and (d) exhibits limited evidence of condition dependence. These patterns provide only limited evidence in support of the sexual selection hypothesis, and no consistent support for any particular sexual selection mechanism; however, more direct measures of how genital morphology influences male fertilization success are required.

Autonomous Rhythmic Drug Delivery Systems Based on Chemical and Biochemomechanical Oscillators

NASA Astrophysics Data System (ADS)

Siegel, Ronald A.

While many drug delivery systems target constant, or zero-order drug release, certain drugs and hormones must be delivered in rhythmic pulses in order to achieve their optimal effect. Here we describe studies with two model autonomous rhythmic delivery systems. The first system is driven by a pH oscillator that modulates the ionization state of a model drug, benzoic acid, which can permeate through a lipophilic membrane when the drug is uncharged. The second system is based on a nonlinear negative feedback instability that arises from coupling of swelling of a hydrogel membrane to an enzymatic reaction, with the hydrogel controlling access of substrate to the enzyme, and the enzyme's product controlling the hydrogel's swelling state. The latter system, whose autonomous oscillations are driven by glucose at constant external activity, is shown to deliver gonadotropin releasing hormone (GnRH) in rhythmic pulses, with periodicity of the same order as observed in sexually mature adult humans. Relevant experimental results and some mathematical models are reviewed.

Internet Pornography Use and Sexual Body Image in a Dutch Sample

PubMed Central

Cranney, Stephen

2016-01-01

Objectives A commonly attributed cause of sexual body image dissatisfaction is pornography use. This relationship has received little verification. Methods The relationship between sexual body image dissatisfaction and Internet pornography use was tested using a large-N sample of Dutch respondents. Results/Conclusion Penis size dissatisfaction is associated with pornography use. The relationship between pornography use and breast size dissatisfaction is null. These results support prior speculation and self-reports about the relationship between pornography use and sexual body image among men. These results also support a prior null finding of the relationship between breast size satisfaction for women and pornography use. PMID:26918066

Size Matters: Penis Size and Sexual Position in Gay Porn Profiles.

PubMed

Brennan, Joseph

2018-01-01

This article combines qualitative and quantitative textual approaches to the representation of penis size and sexual position of performers in 10 of the most visited gay pornography Web sites currently in operation. Specifically, in excess of 6,900 performer profiles sourced from 10 commercial Web sites are analyzed. Textual analysis of the profile descriptions is combined with a quantitative representation of disclosed penis size and sexual position, which is presented visually by two figures. The figures confirm that these sites generally market themselves as featuring penises that are extraordinarily large and find a sample-wide correlation between smaller penis sizes (5-6.5 inches) and receptive sexual acts (bottoming), and larger (8.5-13 inches) with penetrative acts (topping). These observations are supported through the qualitative textual readings of how the performers are described on these popular sites, revealing the narratives and marketing strategies that shape the construction of popular porn brands, performers, and profitable fantasies.

Adolescent Sexual Health Communication and Condom Use: A Meta-Analysis

PubMed Central

Widman, Laura; Noar, Seth M.; Choukas-Bradley, Sophia; Francis, Diane

2014-01-01

Objective Condom use is critical for the health of sexually active adolescents, and yet many adolescents fail to use condoms consistently. One interpersonal factor that may be key to condom use is sexual communication between sexual partners; however, the association between communication and condom use has varied considerably in prior studies of youth. The purpose of this meta-analysis was to synthesize the growing body of research linking adolescents’ sexual communication to condom use, and to examine several moderators of this association. Methods A total of 41 independent effect sizes from 34 studies with 15,046 adolescent participants (Mage=16.8, age range=12–23) were meta-analyzed. Results Results revealed a weighted mean effect size of the sexual communication-condom use relationship of r = .24, which was statistically heterogeneous (Q=618.86, p<.001, I2 =93.54). Effect sizes did not differ significantly by gender, age, recruitment setting, country of study, or condom measurement timeframe; however, communication topic and communication format were statistically significant moderators (p<.001). Larger effect sizes were found for communication about condom use (r = .34) than communication about sexual history (r = .15) or general safer sex topics (r = .14). Effect sizes were also larger for communication behavior formats (r = .27) and self-efficacy formats (r = .28), than for fear/concern (r = .18), future intention (r = .15), or communication comfort (r = −.15) formats. Conclusions Results highlight the urgency of emphasizing communication skills, particularly about condom use, in HIV/STI prevention work for youth. Implications for the future study of sexual communication are discussed. PMID:25133828

Relationships between solid dispersion preparation process, particle size and drug release--an NMR and NMR microimaging study.

PubMed

Dahlberg, Carina; Millqvist-Fureby, Anna; Schuleit, Michael; Furó, István

2010-10-01

Solid dispersion tablets prepared by either spray drying or rotoevaporation and exhibiting different grain and pore sizes were investigated under the process of hydration-swelling-gelation. (2)H and (1)H NMR microimaging experiments were used to selectively follow water penetration and polymer mobilization kinetics, respectively, while the drug release kinetics was followed by (1)H NMR spectroscopy. The obtained data, in combination with morphological information by scanning electron microscopy (SEM), reveal a complex process that ultimately leads to release of the drug into the aqueous phase. We find that the rate of water ingress has no direct influence on release kinetics, which also renders air in the tablets a secondary factor. On the other hand, drug release is directly correlated with the polymer mobilization kinetics. Water diffusion into the originally dry polymer grains determines the rate of grain swelling and the hydration within the grains varies strongly with grain size. We propose that this sets the stage for creating homogeneous gels for small grain sizes and heterogeneous gels for large grain sizes. Fast diffusion through water-rich sections of the inhomogeneous gels that exhibit a large mesh size is the factor which yields a faster drug release from tablets prepared by rotoevaporation. Copyright © 2010. Published by Elsevier B.V.

Prostatitis

MedlinePlus

Prostatitis Overview Prostatitis is swelling and inflammation of the prostate gland, a walnut-sized gland situated directly below the bladder in ... produces fluid (semen) that nourishes and transports sperm. Prostatitis often causes painful or difficult urination. Other symptoms ...

Permeability and selectivity of reverse osmosis membranes: correlation to swelling revisited.

PubMed

Dražević, Emil; Košutić, Krešimir; Freger, Viatcheslav

2014-02-01

Membrane swelling governs both rejection of solutes and permeability of polymeric membranes, however very few data have been available on swelling in water of salt-rejecting reverse osmosis (RO) membranes. This study assesses swelling, thickness and their relation to water permeability for four commercial polyamide (PA) RO membranes (SWC4+, ESPA1, XLE and BW30) using atomic force microscopy (AFM) and attenuated total reflection Fourier transform IR spectroscopy (ATR-FTIR). ATR-FTIR offered a significantly improved estimate of the actual barrier thickness of PA, given AFM is biased by porosity ("fluffy parts") or wiggling of the active layer or presence of a coating layer. Thus obtained intrinsic permeability (permeability times thickness) and selectivity of aromatic polyamides plotted versus swelling falls well on a general trend, along with previously reported data on several common materials showing RO and NF selectivity. The observed general trend may be rationalized by viewing the polymers as a random composite medium containing molecularly small pores. The results suggest that the combination of a rigid low dielectric matrix, limiting the pore size, with multiple hydrophilic H-bonding sites may be a common feature of RO/NF membranes, allowing both high permeability and selectivity. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Allometry, sexual size dimorphism, and niche partitioning in the Mediterranean gecko (Hemidactylus turcicus)

Treesearch

James B. Johnson; Lance D. McBrayer; Daniel Saenz

2005-01-01

Hemidactylus tucrius is a small gekkonid lizard native to the Middle East and Asia that is known to exhibit sexual dimorphism in head size. Several potential explanations exist for the evolution and maintenance of sexual dimorphism in lizards. We tested 2 of these competing hypotheses concerning diet partitioning and differential growth. We found no...

Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat

2014-09-03

The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied.more » The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.« less

Wind, current and swell influences on the ice extent and flux in the Grand Banks-Labrador sea area as observed in the LIMEX '87 experiment

NASA Technical Reports Server (NTRS)

Argus, Susan Digby; Carsey, Frank; Holt, Benjamin

1988-01-01

This paper presents data collected by airborne and satellite instruments during the Labrador Ice Margin Experiment, that demonstrate the effects of oceanic and atmospheric processes on the ice conditions in the Grand Banks-Labrador sea area. Special consideration is given to the development of algorithms for extracting information from SAR data. It is shown that SAR data can be used to monitor ice extent, determine ice motion, locate shear zones, monitor the penetration of swell into the ice, estimate floe sizes, and establish the dimensions of the ice velocity zones. It is also shown that the complex interaction of the ice cover with winds, currents, swell, and coastlines is similar to the dynamics established for a number of sites in both polar regions.

Contribution of the net charge to the regulatory effects of amino acids and epsilon-poly(L-lysine) on the gelatinization behavior of potato starch granules.

PubMed

Ito, Azusa; Hattori, Makoto; Yoshida, Tadashi; Takahashi, Koji

2006-01-01

The effects of lysine (Lys), monosodium glutamate (GluNa), glycine, alanine and epsilon-poly(L-lysine) (PL) with different degrees of polymerization on the gelatinization behavior of potato starch granules were investigated by DSC, viscosity and swelling measurements, microscopic observation, and measurement of the retained amino acid amount to clarify the contribution of the net charge to their regulatory effects on the gelatinization behavior. The amino acids and PL each contributed to an increase in the gelatinization temperature, and a decrease in the peak viscosity and swelling. These effects strongly depended on the absolute value of their net charge. The disappearance of a negative or positive net charge by adjusting the pH value weakened the contribution. The swelling index and size of the potato starch granules changed according to replacement of the swelling medium. The amino acids and PL were easily retained by the swollen potato starch granules according to replacement of the outer solution of the starch granules.

Development of a novel drug release system, time-controlled explosion system (TES). I. Concept and design.

PubMed

Ueda, S; Hata, T; Asakura, S; Yamaguchi, H; Kotani, M; Ueda, Y

1994-01-01

A novel controlled drug release system. Time-Controlled Explosion System (TES) has been developed. TES has a four-layered spherical structure, which consists of core, drug, swelling agent and water insoluble polymer membrane. TES is characterized by a rapid drug release with a precisely programmed lag time; i.e. expansion of the swelling agent by water penetrating through the outer membrane, destruction of the membrane by stress due to swelling force and subsequent rapid drug release. For establishing the concept and development strategy, TES was designed using metoprolol and polystyrene balls (size: 3.2 mm in diameter) as a model drug and core particles. Among the polymers screened, low-substituted hydroxypropylcellulose (L-HPC) and ethylcellulose (EC) were selected for a swelling agent and an outer water insoluble membrane, respectively. The release profiles of metoprolol from the system were not affected by the pH of the dissolution media. Lag time was controlled by the thickness of the outer EC membrane; thus, a combination of TES particles possessing different lag times could offer any desired release profile of the model compound, metoprolol.

Gelatin- and hydroxyapatite-based cryogels for bone tissue engineering: synthesis, characterization, in vitro and in vivo biocompatibility.

PubMed

Kemençe, Nevsal; Bölgen, Nimet

2017-01-01

The aim of this study was the synthesis and characterization of gelatin- and hydroxyapatite (osteoconductive component of bone)-based cryogels for tissue-engineering applications. Preliminary in vitro and in vivo biocompatibility tests were conducted. Gelatin- and hydroxyapatite-based cryogels of varying concentrations were synthesized using glutaraldehyde as the crosslinking agent. Chemical structure, pore morphology, pore size distribution, mechanical properties, swelling characteristics and degradation profiles of the synthesized cryogels were demonstrated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury porosimetry, a mechanical test device, swelling ratio tests and weight loss measurements, respectively. In vitro cell viability and in vivo biocompatility tests were performed in order to show the performance of the cryogels in the biological environment. Changing the concentrations of gelatin, hydroxyapatite and crosslinker changed the chemical structure, pore size and pore size distribution of the cryogels, which in turn resulted in the ultimate behaviour (mechanical properties, swelling ratio, degradation profile). In vitro cell culture tests showed the viability of the cells. The cryogels did not show any cytotoxic effects on the cells. Clinical outcomes and the gross pathological results demonstrated that there was no necrosis noted in the abdominal and thoracic regions at the end of implantation and the implanted cryogel was found to be non-irritant and non-toxic at 12 weeks of implantation. Copyright © 2013 John Wiley & Sons, Ltd. Copyright © 2013 John Wiley & Sons, Ltd.

Thiol-Capped Gold Nanoparticles Swell-Encapsulated into Polyurethane as Powerful Antibacterial Surfaces Under Dark and Light Conditions

PubMed Central

Macdonald, Thomas J.; Wu, Ke; Sehmi, Sandeep K.; Noimark, Sacha; Peveler, William J.; du Toit, Hendrik; Voelcker, Nicolas H.; Allan, Elaine; MacRobert, Alexander J.; Gavriilidis, Asterios; Parkin, Ivan P.

2016-01-01

A simple procedure to develop antibacterial surfaces using thiol-capped gold nanoparticles (AuNPs) is shown, which effectively kill bacteria under dark and light conditions. The effect of AuNP size and concentration on photo-activated antibacterial surfaces is reported and we show significant size effects, as well as bactericidal activity with crystal violet (CV) coated polyurethane. These materials have been proven to be powerful antibacterial surfaces against both Gram-positive and Gram-negative bacteria. AuNPs of 2, 3 or 5 nm diameter were swell-encapsulated into PU before a coating of CV was applied (known as PU-AuNPs-CV). The antibacterial activity of PU-AuNPs-CV samples was tested against Staphylococcus aureus and Escherichia coli as representative Gram-positive and Gram-negative bacteria under dark and light conditions. All light conditions in this study simulated a typical white-light hospital environment. This work demonstrates that the antibacterial activity of PU-AuNPs-CV samples and the synergistic enhancement of photoactivity of triarylmethane type dyes is highly dependent on nanoparticle size and concentration. The most powerful PU-AuNPs-CV antibacterial surfaces were achieved using 1.0 mg mL−1 swell encapsulation concentrations of 2 nm AuNPs. After two hours, Gram-positive and Gram-negative bacteria were reduced to below the detection limit (>4 log) under dark and light conditions. PMID:27982122

The Relationship Between Digit Ratio (2D:4D) and Sexual Orientation in Men from China.

PubMed

Xu, Yin; Zheng, Yong

2016-04-01

We examined the relationship between 2D:4D digit ratio and sexual orientation in men from China and analyzed the influences of the components used to assess sexual orientation and the criteria used to classify individuals as homosexual on this relationship. A total of 309 male and 110 female participants took part in a web-based survey. Our results showed that heterosexual men had a significantly lower 2D:4D than heterosexual women and exclusively homosexual men had a significantly higher left 2D:4D than heterosexual men whereas only exclusively homosexual men had a significantly higher right 2D:4D than heterosexual men when sexual orientation was assessed via sexual attraction. The left 2D:4D showed a significant positive correlation with sexual identity, sexual attraction, and sexual behavior, and the right 2D:4D showed a significant positive correlation with sexual attraction. The effect sizes for differences in 2D:4D between homosexual and heterosexual men varied according to criteria used to classify individuals as homosexual and sexual orientation components; the more stringent the criteria (scores closer to the homosexual category), the larger the effect sizes; further, sexual attraction yielded the largest effect size. There were no significant effects of age and latitude on Chinese 2D:4D. This study contributes to the current understanding of the relationship between 2D:4D and male sexual orientation.

Simulation of controllable permeation in PNIPAAm coated membranes

NASA Astrophysics Data System (ADS)

Ehrenhofer, Adrian; Wallmersperger, Thomas; Richter, Andreas

2016-04-01

Membranes separate fluid compartments and can comprise transport structures for selective permeation. In biology, channel proteins are specialized in their atomic structure to allow transport of specific compounds (selectivity). Conformational changes in protein structure allow the control of the permeation abilities by outer stimuli (gating). In polymeric membranes, the selectivity is due to electrostatic or size-exclusion. It can thus be controlled by size variation or electric charges. Controllable permeation can be useful to determine particle-size distributions in continuous flow, e.g. in microfluidics and biomedicine to gain cell diameter profiles in blood. The present approach uses patterned polyethylene terephthalate (PET) membranes with hydrogel surface coating for permeation control by size-exclusion. The thermosensitive hydrogel poly(N-isopropylacrylamide) (PNIPAAm) is structured with a cross-shaped pore geometry. A change in the temperature of the water flow through the membrane leads to a pore shape variation. The temperature dependent behavior of PNIPAAm can be numerically modeled with a temperature expansion model, where the swelling and deswelling is depicted by temperature dependent expansion coefficients. In the present study, the free swelling behavior was implemented to the Finite Element tool ABAQUS for the complex composite structure of the permeation control membrane. Experimental values of the geometry characteristics were derived from microscopy images with the tool Image J and compared to simulation results. Numerical simulations using the derived thermo-mechanical model for different pore geometries (circular, rectangle, cross and triangle) were performed. With this study, we show that the temperature expansion model with values from the free swelling behavior can be used to adequately predict the deformation behavior of the complex membrane system. The predictions can be used to optimize the behavior of the membrane pores and the overall performance of the smart membrane.

Penile fracture following husband abuse: a case report.

PubMed

Dienye, Paul O; Jebbin, Nze J; Gbeneol, Precious K

2009-12-01

The case of a 35-year-old fisherman who presented in a rural clinic with a sudden onset of painful penile swelling affecting the left lateral side with associated rapid detumescence is reported. He had tried to coerce his wife to a sexual intercourse when she forcefully bent his penis. He was initially managed with cold applications, oral diclofenac potassium, chymoral, and splinting of the penis and then referred to the urological services of a teaching hospital. He defaulted only to re-present about 2 weeks later with some improvement in his symptoms. Further advice to see the urologist was also rebuffed on financial grounds. When he reported about 1 month later, he was assessed to have grade 3 erectile dysfunction. In conclusion, penile fracture is a rare condition which follows unphysiological bending of the tumescent penis during sexual intercourse or masturbation. That following husband abuse is rarer. The sequelae can be devastating.

Examining the Job-Related, Psychological, and Physical Outcomes of Workplace Sexual Harassment: A Meta-Analytic Review

ERIC Educational Resources Information Center

Chan, Darius K-S.; Lam, Chun Bun; Chow, Suk Yee; Cheung, Shu Fai

2008-01-01

This study was designed to examine the job-related, psychological, and physical outcomes of sexual harassment in the workplace. Using a meta-analytic approach, we analyzed findings from 49 primary studies, with a total sample size of 89,382, to obtain estimates of the population mean effect size of the association between sexual harassment and…

What can asymmetry tell us? Investigation of asymmetric versus symmetric pinch and swell structures in nature and simulation

NASA Astrophysics Data System (ADS)

Gardner, Robyn; Piazolo, Sandra; Daczko, Nathan

2015-04-01

Pinch and swell structures occur from microscopic to landscape scales where a more competent layer in a weaker matrix is deformed by pure shear, often in rifting environments. The Anita Shear Zone (ASZ) in Fiordland, New Zealand has an example of landscape scale (1 km width) asymmetric pinch and swell structures developed in ultramafic rocks. Field work suggests that the asymmetry is a result of variations in the surrounding 'matrix' flow properties as the ultramafic band is surrounded to the east by an orthogneiss (Milford Orthogneiss) and to the west by a paragneiss (Thurso Paragneiss). In addition, there is a narrow and a much wider shear zone between the ultramafics and the orthogneiss and paragneiss, respectively. Detailed EBSD analysis of samples from a traverse across the pinch and swell structure indicate the ultramafics in the shear zone on the orthogneiss side have larger grain size than the ultramafics in the shear zone on the paragneiss side. Ultramafic samples from the highly strained paragneiss and orthogneiss shear zones show dislocation creep behaviour, and, on the paragneiss side, also significant deformation by grain boundary sliding. To test if asymmetry of pinch and swell structures can be used to derive the rheological properties of not only the pinch and swell lithologies, but also of the matrix, numerical simulations were performed. Numerical modelling of pure shear (extension) was undertaken with (I) initially three layers and then (II) five layers by adding soft high strain zones on both sides of the rheological hard layer. The matrix was given first symmetric, then asymmetric viscosity. Matrix viscosity was found to impact the formation of pinch and swell structures with the weaker layer causing increased tortuosity of the competent layer edge due to increased local differential stress. Results highlight that local, rheologically soft layers and the relative viscosity of matrix both impact significantly the shape and symmetry of developing pinch and swell structures.

Fuel swelling and interaction layer formation in the SELENIUM Si and ZrN coated U(Mo) dispersion fuel plates irradiated at high power in BR2

NASA Astrophysics Data System (ADS)

Leenaers, A.; Van den Berghe, S.; Koonen, E.; Kuzminov, V.; Detavernier, C.

2015-03-01

In the framework of the SELENIUM project two full size flat fuel plates were produced with respectively Si and ZrN coated U(Mo) particles and irradiated in the BR2 reactor at SCK•CEN. Non-destructive analysis of the plates showed that the fuel swelling profiles of both SELENIUM plates were very similar to each other and none of the plates showed signs of pillowing or excessive swelling at the end of irradiation at the highest power position (local maximum 70% 235U). The microstructural analysis showed that the Si coated fuel has less interaction phase formation at low burn-up but at the highest burn-ups, defects start to develop on the IL-matrix interface. The ZrN coated fuel, shows a virtual absence of reaction between the U(Mo) and the Al, up to high fission densities after which the interaction layer formation starts and defects develop in the matrix near the U(Mo) particles. It was found and is confirmed by the SELENIUM (Surface Engineering of Low ENrIched Uranium-Molybdenum) experiment that there are two phenomena at play that need to be controlled: the formation of an interaction layer and swelling of the fuel. As the interaction layer formation occurs at the U(Mo)-matrix interface, applying a diffusion barrier (coating) at that interface should prevent the interaction between U(Mo) and the matrix. The U(Mo) swelling, observed to proceed at an accelerating rate with respect to fission density accumulation, is governed by linear solid state swelling and fission gas bubble swelling due to recrystallization of the fuel. The examination of the SELENIUM fuel plates clearly show that for the U(Mo) dispersion fuel to be qualified, the swelling rate at high burn-up needs to be reduced.

Inferences on mating and sexual systems of two Pacific Cinetorhynchus shrimps (Decapoda, Rhynchocinetidae) based on sexual dimorphism in body size and cheliped weaponry.

PubMed

Bauer, Raymond T; Okuno, Junji; Thiel, Martin

2014-01-01

Sexual dimorphism in body size and weaponry was examined in two Cinetorhynchus shrimp species in order to formulate hypotheses on their sexual and mating systems. Collections of Cinetorhynchus sp. A and Cinetorhynchus sp. B were made in March, 2011 on Coconut Island, Hawaii, by hand dipnetting and minnow traps in coral rubble bottom in shallow water. Although there is overlap in male and female size, some males are much larger than females. The major (pereopod 1) chelipeds of males are significantly larger and longer than those of females. In these two Cinetorhynchus species, males and females have third maxillipeds of similar relative size, i.e., those of males are not hypertrophied and probably not used as spear-like weapons as in some other rhynchocinetid (Rhynchocinetes) species. Major chelae of males vary with size, changing from typical female-like chelae tipped with black corneous stout setae to subchelate or prehensile appendages in larger males. Puncture wounds or regenerating major chelipeds were observed in 26.1 % of males examined (N = 38 including both species). We interpret this evidence on sexual dimorphism as an indication of a temporary male mate guarding or "neighborhoods of dominance" mating system, in which larger dominant robustus males defend females and have greater mating success than smaller males. Fecundity of females increased with female size, as in most caridean species (500-800 in Cinetorhynchus sp. A; 300-3800 in Cinetorhynchus sp. B). Based on the sample examined, we conclude that these two species have a gonochoric sexual system (separate sexes) like most but not all other rhynchocinetid species in which the sexual system has been investigated.

Intraspecific competition and light effect on reproduction of Ligularia virgaurea, an invasive native alpine grassland clonal herb

PubMed Central

Xie, Tian-peng; Zhang, Ge-fei; Zhao, Zhi-gang; Du, Guo-zhen; He, Gui-yong

2014-01-01

The relationship between sexual reproduction and clonal growth in clonal plants often shows up at the ramet level. However, only a few studies focus on the relationship at the genet level, which could finally account for evolution. The sexual reproduction and clonal growth of Ligularia virgaurea, a perennial herb widely distributed in the alpine grasslands of the Qinghai-Tibetan Plateau of China, were studied under different competition intensities and light conditions at the genet level through a potted experiment. The results showed that: (1) sexual reproduction did not depend on density or light, and increasing clonal growth with decreasing density and increasing light intensity indicated that intraspecific competition and light intensity may affect the clonal life history of L. virgaurea; (2) both sexual reproduction and clonal growth show a positive linear relationship with genet size under different densities and light conditions; (3) a threshold size is required for sexual reproduction and no evidence of a threshold size for clonal growth under different densities and light conditions; (4) light level affected the allocation of total biomass to clonal and sexual structures, with less allocation to clonal structures and more allocation to sexual structures in full sunlight than in shade; (5) light determined the onset of sexual reproduction, and the genets in the shade required a smaller threshold size for sexual reproduction to occur than the plants in full sunlight; and (6) no evidence was found of trade-offs between clonal growth and sexual reproduction under different densities and light conditions at the genet level, and the positive correlation between two reproductive modes indicated that these are two integrated processes. Clonal growth in this species may be viewed as a growth strategy that tends to maximize genet fitness. PMID:24683463

Spatial and temporal variation in size of polar bear (Ursus maritimus) sexual organs and its use in pollution and climate change studies.

PubMed

Sonne, Christian; Dietz, Rune; Born, Erik W; Riget, Frank F; Leifsson, Pall S; Bechshøft, Thea Ø; Kirkegaard, Maja

2007-11-15

Sexual organs and their development are susceptible to atmospheric transported environmental xenoendocrine pollutants and climate change (food availability). We therefore investigated sexual organs from 55 male and 44 female East Greenland polar bears (Ursus maritimus) to obtain information about growth/size and sexual maturity. Then, the genitalia size was compared with those previously reported from Canadian and Svalbard polar bears. Growth models showed that East Greenland male polar bears reached sexual maturity around 7 years of age and females around 4 years of age. When comparing East Greenland and Svalbard polar bears, the size of baculum and uterus were significantly lower in the East Greenland polar bears (ANOVA: all p < 0.05). Based on previously published baculum mean values from Canadian polar bears, a similar baculum pattern was found for East Greenland vs. Canadian polar bears. It is speculated whether this could be a result of the general high variation in polar bear body size, temporal distribution patterns of anthropogenic long-range transported persistent organic pollutants or climate change (decreasing food availability). The present investigation represents conservation and background data for future spatial and temporal assessments of hunting, pollution and climate change scenarios.

Novel host plant leads to the loss of sexual dimorphism in a sexually selected male weapon.

PubMed

Allen, Pablo E; Miller, Christine W

2017-08-16

In this time of massive global change, species are now frequently interacting with novel players. Greater insight into the impact of these novel interactions on traits linked to fitness is essential, because effects on these traits can hinder population existence or promote rapid adaptation. Sexually selected weapons and ornaments frequently influence fitness and often have heightened condition-dependence in response to nutrition. Condition-dependence in response to different ecological conditions, a form of developmental plasticity, may be responsible for much of the intraspecific variation in sexually selected ornaments and weapons in wild populations. Here we examined the consequences of developing on a novel plant for the expression of size and shape in the leaf-footed cactus bug Narnia femorata (Hemiptera: Coreidae). The males of this species possess enlarged, sexually dimorphic femurs on their hind legs. These legs are used as weapons in male-male contests. Females are typically larger in overall body size. Our study revealed that developing upon a novel host can lead to pronounced phenotypically plastic change in sexually dimorphic traits. Male hind femurs were greatly impacted by the novel diet to the extent that the sexual dimorphism in hind femurs was lost. Further, dimorphism in body size increased, as males became tiny adults while females better maintained their body size. These patterns underscore the complex effects that novel species interactions may have on sexual phenotypes. © 2017 The Author(s).

Penile paraffinoma after subcutaneous injection of paraffin. Treatment with a two step cutaneous plasty of the penile shaft with scrotal skin.

PubMed

Oñate Celdrán, Julián; Sanchez Rodríguez, Carlos; Tomás Ros, Mariano; González Valverde, Francisco Miguel; Morga Egea, Juan Pedro; Ruiz Marín, Miguel; Valdelvira Nadal, Pedro; Jiménez López, José Miguel; Fontana Compiano, Luis Oscar

2012-06-01

To report a rare case of penile paraffinoma caused by the subcutaneous or intra-urethral injection of foreign substances containing long-chain saturated hydrocarbons. These were injected in order to increase the penis size which generated a chronic granulomatous inflammatory reaction. This is a rare practice in the western world. We present the case of a 32-year-old Bulgarian male who presented with a two-year history of elastic, slightly painful penis swelling after subcutaneous liquid paraffin injection. The proposed treatment was excision of the affected tissue and penile reconstruction in a two-stage procedure. The operative procedure was successful and the patient had good aesthetic and functional results. Paraffin and other materials injected into the penis can produce many complications. Foreign body granuloma, skin necrosis, penile deformity, chronic and unhealed ulcer, painful erection, and the inability to achieve a satisfactory sexual relationship are some of the resulting complications. Intralesional or systemic steroids have been used in primary sclerosing lipogranuloma resulting in the disappearance of the granuloma, but in our opinion the treatment of choice should be radical excision, and, if necessary, secondary reconstruction of the penis. The injection of foreign substances to enhance penis size is currently an unjustifiable practice. However, it is still carried out, especially in Eastern Europe and Asia. In most cases surgical treatment is needed to treat the complications and the best modality seems to be radical excision together with follow-up.

Geometric morphometrics reveals sex-differential shape allometry in a spider.

PubMed

Fernández-Montraveta, Carmen; Marugán-Lobón, Jesús

2017-01-01

Common scientific wisdom assumes that spider sexual dimorphism (SD) mostly results from sexual selection operating on males. However, testing predictions from this hypothesis, particularly male size hyperallometry, has been restricted by methodological constraints. Here, using geometric morphometrics (GMM) we studied for the first time sex-differential shape allometry in a spider ( Donacosa merlini , Araneae: Lycosidae) known to exhibit the reverse pattern (i.e., male-biased) of spider sexual size dimorphism. GMM reveals previously undetected sex-differential shape allometry and sex-related shape differences that are size independent (i.e., associated to the y-intercept, and not to size scaling). Sexual shape dimorphism affects both the relative carapace-to-opisthosoma size and the carapace geometry, arguably resulting from sex differences in both reproductive roles (female egg load and male competition) and life styles (wandering males and burrowing females). Our results demonstrate that body portions may vary modularly in response to different selection pressures, giving rise to sex differences in shape, which reconciles previously considered mutually exclusive interpretations about the origins of spider SD.

Nuclear radiation actuated valve

DOEpatents

Christiansen, David W.; Schively, Dixon P.

1985-01-01

A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

Polysaccharide metallohydrogel obtained from Salecan and trivalent chromium: Synthesis and characterization.

PubMed

Su, Ting; Qi, Xiaoliang; Zuo, Gancheng; Pan, Xihao; Zhang, Jianfa; Han, Zhiwei; Dong, Wei

2018-02-01

Here, a new kind of Salecan derived polysaccharide metallohydrogel was reported. Successful fabrication of Salecan metallohydrogel was verified by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and rheological measurements. Scanning electron microscope investigations have been conducted to elucidate the morphology of Salecan/Cr 3+ gel (SCgel). We found that the pore size of metallohydrogel can be tailored by adjusting the Cr 3+ dose during gel formation. After that, swelling and de-swelling behaviors were systematically studied. The increasing of chromium ion concentration and the presence of saline solutions will cause the decrease of swelling percentage. It is assumed that the decreasing hydrophilicity of Salecan, the increase of crosslinking density, and the complexation of the carboxylate group with saline ions are the main syneresis mechanisms. Altogether, this study opens a new avenue to prapare Salecan-based hydrogel. Copyright © 2017 Elsevier Ltd. All rights reserved.

Swelling-induced wrinkling in layered gel beams

NASA Astrophysics Data System (ADS)

Nardinocchi, P.; Puntel, E.

2017-11-01

Gels are widely employed in smart mechanical devices and biomedical applications. Swelling-induced bending actuation can be obtained by means of a simple bilayer gel beam. We show that this system can also exhibit wrinkling patterns of potential interest for structural morphing and sensing. We study swelling-induced wrinkling at the extrados of a bilayer gel beam with the softer layer on top. The bent configuration at finite strain is recovered first and, starting from it, a linear perturbation analysis is performed. We delimit the zone corresponding to wrinkling modes in a parameter plane encompassing a mechanical stiffness ratio and a geometric top layer to total height ratio. Interestingly, we observe that surface instability precedes and envelopes wrinkling modes of finite wavelength. Finally, we discuss the effect of changes in stiffness and of the Flory-Huggins parameters χ on the size of the wrinkling domain.

Micropore analysis of polymer networks by gas sorption and 129Xe NMR spectroscopy: toward a better understanding of intrinsic microporosity.

PubMed

Weber, Jens; Schmidt, Johannes; Thomas, Arne; Böhlmann, Winfried

2010-10-05

The microporosity of two microporous polymer networks is investigated in detail. Both networks are based on a central spirobifluorene motif but have different linker groups, namely, imide and thiophene units. The microporosity of the networks is based on the "polymers of intrinsic microporosity (PIM)" design strategy. Nitrogen, argon, and carbon dioxide were used as sorbates in order to analyze the microporosity in greater detail. The gas sorption data was analyzed with respect to important parameters such as specific surface area, pore volume, and pore size (distribution). It is shown that the results can be strongly model dependent and swelling effects have to be regarded. (129)Xe NMR was used as an independent technique for the estimation of the average pore size of the polymer networks. The results indicate that both networks are mainly ultramicroporous (pore sizes < 0.8 nm) in the dry state, which was not expected based on the molecular design. Phase separation and network defects might influence the overall network morphology strongly. Finally, the observed swelling indicates that this "soft" microporous matter might have a different micropore size in the solvent swollen/filled state that in the dry state.

Design of asymmetric particles containing a charged interior and a neutral surface charge: comparative study on in vivo circulation of polyelectrolyte microgels.

PubMed

Chen, Kai; Xu, Jing; Luft, J Christopher; Tian, Shaomin; Raval, Jay S; DeSimone, Joseph M

2014-07-16

Lowering the modulus of hydrogel particles could enable them to bypass in vivo physical barriers that would otherwise filter particles with similar size but higher modulus. Incorporation of electrolyte moieties into the polymer network of hydrogel particles to increase the swelling ratio is a straightforward and quite efficient way to decrease the modulus. In addition, charged groups in hydrogel particles can also help secure cargoes. However, the distribution of charged groups on the surface of a particle can accelerate the clearance of particles. Herein, we developed a method to synthesize highly swollen microgels of precise size with near-neutral surface charge while retaining interior charged groups. A strategy was employed to enable a particle to be highly cross-linked with very small mesh size, and subsequently PEGylated to quench the exterior amines only without affecting the internal amines. Acidic degradation of the cross-linker allows for swelling of the particles to microgels with a desired size and deformability. The microgels fabricated demonstrated extended circulation in vivo compared to their counterparts with a charged surface, and could potentially be utilized in in vivo applications including as oxygen carriers or nucleic acid scavengers.

The influence of product brand-to-brand variability on superdisintegrant Performance. A case study with croscarmellose sodium.

PubMed

Zhao, Na; Augsburger, L L

2006-01-01

The purpose of this study is to investigate factors influencing croscarmellose sodium functionality with special emphasis on developing a discriminating model tablet formulation to evaluate product brand-to-brand variability. The particle size distribution, water uptake, and swelling properties of five brands of croscarmellose sodium in either neutral water or 0.1 N HCl were studied. Differences were observed in all properties between brands. Media with acidic pH had a negative impact, but to different extents, on both the water uptake and swelling of all croscarmellose sodium brands due to the presence of carboxymethyl sodium substituents. A tablet matrix composed of lactose (75% w/w) and dicalcium phosphate (25% wt/wt) was used to compare the functional equivalency of the five brands of croscarmellose sodium. The tablet disintegration times were inversely proportional to the swelling ability of superdisintegrant in the testing medium regardless of medium temperature and disintegrant concentration. In conclusion; the particle size, total degree of substitution, and the ratio of basic to acidic substituents are important factors that should be considered during product optimization. The tablet matrix composed of lactose and dicalcium phosphate at a weight ratio of 3:1 can be used as a model formulation for product lot-to-lot consistency and product brand-to-brand comparison purposes.

Osmotic Engine: Translating Osmotic Pressure into Macroscopic Mechanical Force via Poly(Acrylic Acid) Based Hydrogels

PubMed Central

Arens, Lukas; Weißenfeld, Felix; Klein, Christopher O.; Schlag, Karin

2017-01-01

Poly(acrylic acid)‐based hydrogels can swell up to 100–1000 times their own weight in desalinated water due to osmotic forces. As the swelling is about a factor of 2–12 lower in seawater‐like saline solutions (4.3 wt% NaCl) than in deionized water, cyclic swelling, and shrinking can potentially be used to move a piston in an osmotic motor. Consequently, chemical energy is translated into mechanical energy. This conversion is driven by differences in chemical potential and by changes in entropy. This is special, as most thermodynamic engines rely instead on the conversion of heat into mechanical energy. To optimize the efficiency of this process, the degree of neutralization, the degree of crosslinking, and the particle size of the hydrogels are varied. Additionally, different osmotic engine prototypes are constructed. The maximum mean power of 0.23 W kg−1 dry hydrogel is found by using an external load of 6 kPa, a polymer with 1.7 mol% crosslinking, a degree of neutralization of 10 mol%, and a particle size of 370–670 µm. As this is achieved only in the first round of optimization, higher values of the maximum power average over one cycle seem realistic. PMID:28932675

Size-assortative mating and sexual size dimorphism are predictable from simple mechanics of mate-grasping behavior

PubMed Central

2010-01-01

Background A major challenge in evolutionary biology is to understand the typically complex interactions between diverse counter-balancing factors of Darwinian selection for size assortative mating and sexual size dimorphism. It appears that rarely a simple mechanism could provide a major explanation of these phenomena. Mechanics of behaviors can predict animal morphology, such like adaptations to locomotion in animals from various of taxa, but its potential to predict size-assortative mating and its evolutionary consequences has been less explored. Mate-grasping by males, using specialized adaptive morphologies of their forelegs, midlegs or even antennae wrapped around female body at specific locations, is a general mating strategy of many animals, but the contribution of the mechanics of this wide-spread behavior to the evolution of mating behavior and sexual size dimorphism has been largely ignored. Results Here, we explore the consequences of a simple, and previously ignored, fact that in a grasping posture the position of the male's grasping appendages relative to the female's body is often a function of body size difference between the sexes. Using an approach taken from robot mechanics we model coercive grasping of females by water strider Gerris gracilicornis males during mating initiation struggles. We determine that the male optimal size (relative to the female size), which gives the males the highest grasping force, properly predicts the experimentally measured highest mating success. Through field sampling and simulation modeling of a natural population we determine that the simple mechanical model, which ignores most of the other hypothetical counter-balancing selection pressures on body size, is sufficient to account for size-assortative mating pattern as well as species-specific sexual dimorphism in body size of G. gracilicornis. Conclusion The results indicate how a simple and previously overlooked physical mechanism common in many taxa is sufficient to account for, or importantly contribute to, size-assortative mating and its consequences for the evolution of sexual size dimorphism. PMID:21092131

Parallel evolution of sexual isolation in sticklebacks.

PubMed

Boughman, Janette Wenrick; Rundle, Howard D; Schluter, Dolph

2005-02-01

Mechanisms of speciation are not well understood, despite decades of study. Recent work has focused on how natural and sexual selection cause sexual isolation. Here, we investigate the roles of divergent natural and sexual selection in the evolution of sexual isolation between sympatric species of threespine sticklebacks. We test the importance of morphological and behavioral traits in conferring sexual isolation and examine to what extent these traits have diverged in parallel between multiple, independently evolved species pairs. We use the patterns of evolution in ecological and mating traits to infer the likely nature of selection on sexual isolation. Strong parallel evolution implicates ecologically based divergent natural and/or sexual selection, whereas arbitrary directionality implicates nonecological sexual selection or drift. In multiple pairs we find that sexual isolation arises in the same way: assortative mating on body size and asymmetric isolation due to male nuptial color. Body size and color have diverged in a strongly parallel manner, similar to ecological traits. The data implicate ecologically based divergent natural and sexual selection as engines of speciation in this group.

Sexual selection versus alternative causes of sexual dimorphism in teiid lizards.

PubMed

Anderson, Roger A; Vitt, Laurie J

1990-09-01

The presence and extent of sexual dimorphisms in body form (size and shape) of adult macroteiid lizards were investigated. Males were significantly larger than females in the temperate species, Cnemidophorus tigris, and in the tropical species, Ameiva ameiva and C. ocellifer. Young adult C. tigris males grew faster than young adult females within and between reproductive seasons. Adult males of all species had larger heads than adult females of the same body size; this difference increased with body size. Moreover, male C. tigris were heavier than females of the same snout-vent length. The causes and consequences of the sexual dimorphisms were also examined. The possible causes of body size are especially numerous, and distinguishing the relative influences of the various causal selection factors on body size is problematical. Nevertheless, observational field data were used to tentatively conclude that intrasexual selection was the cause of larger body size of C. tigris males relative to females because (1) larger males won in male aggressive interactions, (2) the winning males gained access to more females by repelling competitors and by female acceptance, (3) larger males consequently had higher reproductive success, and (4) other hypothetical causes of larger male size were unsupported.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liang, Linyun; Mei, Zhi -Gang; Kim, Yeon Soo

A mesoscale model is developed by integrating the rate theory and phase-field models and is used to study the fission-induced recrystallization in U-7Mo alloy. The rate theory model is used to predict the dislocation density and the recrystallization nuclei density due to irradiation. The predicted fission rate and temperature dependences of the dislocation density are in good agreement with experimental measurements. This information is used as input for the multiphase phase-field model to investigate the fission-induced recrystallization kinetics. The simulated recrystallization volume fraction and bubble induced swelling agree well with experimental data. The effects of the fission rate, initial grainmore » size, and grain morphology on the recrystallization kinetics are discussed based on an analysis of recrystallization growth rate using the modified Avrami equation. Here, we conclude that the initial microstructure of the U-Mo fuels, especially the grain size, can be used to effectively control the rate of fission-induced recrystallization and therefore swelling.« less

Multi-Shell Hollow Nanogels with Responsive Shell Permeability

PubMed Central

Schmid, Andreas J.; Dubbert, Janine; Rudov, Andrey A.; Pedersen, Jan Skov; Lindner, Peter; Karg, Matthias; Potemkin, Igor I.; Richtering, Walter

2016-01-01

We report on hollow shell-shell nanogels with two polymer shells that have different volume phase transition temperatures. By means of small angle neutron scattering (SANS) employing contrast variation and molecular dynamics (MD) simulations we show that hollow shell-shell nanocontainers are ideal systems for controlled drug delivery: The temperature responsive swelling of the inner shell controls the uptake and release, while the thermoresponsive swelling of the outer shell controls the size of the void and the colloidal stability. At temperatures between 32 °C < T < 42 °C, the hollow nanocontainers provide a significant void, which is even larger than the initial core size of the template, and they possess a high colloidal stability due to the steric stabilization of the swollen outer shell. Computer simulations showed, that temperature induced switching of the permeability of the inner shell allows for the encapsulation in and release of molecules from the cavity. PMID:26984478

Synthesis and Characterization of Poly(Ethylene Glycol) Based Thermo-Responsive Hydrogels for Cell Sheet Engineering.

PubMed

Son, Kuk Hui; Lee, Jin Woo

2016-10-20

The swelling properties and thermal transition of hydrogels can be tailored by changing the hydrophilic-hydrophobic balance of polymer networks. Especially, poly( N -isopropylacrylamide) (PNIPAm) has received attention as thermo-responsive hydrogels for tissue engineering because its hydrophobicity and swelling property are transited around body temperature (32 °C). In this study, we investigated the potential of poly(ethylene glycol) diacrylate (PEGDA) as a hydrophilic co-monomer and crosslinker of PNIPAm to enhance biological properties of PNIPAm hydrogels. The swelling ratios, lower critical solution temperature (LCST), and internal pore structure of the synthesized p(NIPAm- co -PEGDA) hydrogels could be varied with changes in the molecular weight of PEGDA and the co-monomer ratios (NIPAm to PEGDA). We found that increasing the molecular weight of PEGDA showed an increase of pore sizes and swelling ratios of the hydrogels. In contrast, increasing the weight ratio of PEGDA under the same molecular weight condition increased the crosslinking density and decreased the swelling ratios of the hydrogels. Further, to evaluate the potential of these hydrogels as cell sheets, we seeded bovine chondrocytes on the p(NIPAm- co -PEGDA) hydrogels and observed the proliferation of the seed cells and their detachment as a cell sheet upon a decrease in temperature. Based on our results, we confirmed that p(NIPAm- co -PEGDA) hydrogels could be utilized as cell sheets with enhanced cell proliferation performance.

Body Size, Fecundity, and Sexual Size Dimorphism in the Neotropical Cricket Macroanaxipha macilenta (Saussure) (Orthoptera: Gryllidae).

PubMed

Cueva Del Castillo, R

2015-04-01

Body size is directly or indirectly correlated with fitness. Body size, which conveys maximal fitness, often differs between sexes. Sexual size dimorphism (SSD) evolves because body size tends to be related to reproductive success through different pathways in males and females. In general, female insects are larger than males, suggesting that natural selection for high female fecundity could be stronger than sexual selection in males. I assessed the role of body size and fecundity in SSD in the Neotropical cricket Macroanaxipha macilenta (Saussure). This species shows a SSD bias toward males. Females did not present a correlation between number of eggs and body size. Nonetheless, there were fluctuations in the number of eggs carried by females during the sampling period, and the size of females that were collected carrying eggs was larger than that of females collected with no eggs. Since mating induces vitellogenesis in some cricket species, differences in female body size might suggest male mate choice. Sexual selection in the body size of males of M. macilenta may possibly be stronger than the selection of female fecundity. Even so, no mating behavior was observed during the field observations, including audible male calling or courtship songs, yet males may produce ultrasonic calls due to their size. If female body size in M. macilenta is not directly related to fecundity, the lack of a correlated response to selection on female body size could represent an alternate evolutionary pathway in the evolution of body size and SSD in insects.

Spore development and nuclear inheritance in arbuscular mycorrhizal fungi

PubMed Central

2011-01-01

Background A conventional tenet of classical genetics is that progeny inherit half their genome from each parent in sexual reproduction instead of the complete genome transferred to each daughter during asexual reproduction. The transmission of hereditary characteristics from parents to their offspring is therefore predictable, although several exceptions are known. Heredity in microorganisms, however, can be very complex, and even unknown as is the case for coenocytic organisms such as Arbuscular Mycorrhizal Fungi (AMF). This group of fungi are plant-root symbionts, ubiquitous in most ecosystems, which reproduce asexually via multinucleate spores for which sexuality has not yet been observed. Results We examined the number of nuclei per spore of four AMF taxa using high Z-resolution live confocal microscopy and found that the number of nuclei was correlated with spore diameter. We show that AMF have the ability, through the establishment of new symbioses, to pass hundreds of nuclei to subsequent generations of multinucleated spores. More importantly, we observed surprising heterogeneity in the number of nuclei among sister spores and show that massive nuclear migration and mitosis are the mechanisms by which AMF spores are formed. We followed spore development of Glomus irregulare from hyphal swelling to spore maturity and found that the spores reached mature size within 30 to 60 days, and that the number of nuclei per spores increased over time. Conclusions We conclude that the spores used for dispersal of AMF contain nuclei with two origins, those that migrate into the spore and those that arise by mitosis in the spore. Therefore, these spores do not represent a stage in the life cycle with a single nucleus, raising the possibility that AMF, unlike all other known eukaryotic organisms, lack the genetic bottleneck of a single-nucleus stage. PMID:21349193

Spore development and nuclear inheritance in arbuscular mycorrhizal fungi.

PubMed

Marleau, Julie; Dalpé, Yolande; St-Arnaud, Marc; Hijri, Mohamed

2011-02-24

A conventional tenet of classical genetics is that progeny inherit half their genome from each parent in sexual reproduction instead of the complete genome transferred to each daughter during asexual reproduction. The transmission of hereditary characteristics from parents to their offspring is therefore predictable, although several exceptions are known. Heredity in microorganisms, however, can be very complex, and even unknown as is the case for coenocytic organisms such as Arbuscular Mycorrhizal Fungi (AMF). This group of fungi are plant-root symbionts, ubiquitous in most ecosystems, which reproduce asexually via multinucleate spores for which sexuality has not yet been observed. We examined the number of nuclei per spore of four AMF taxa using high Z-resolution live confocal microscopy and found that the number of nuclei was correlated with spore diameter. We show that AMF have the ability, through the establishment of new symbioses, to pass hundreds of nuclei to subsequent generations of multinucleated spores. More importantly, we observed surprising heterogeneity in the number of nuclei among sister spores and show that massive nuclear migration and mitosis are the mechanisms by which AMF spores are formed. We followed spore development of Glomus irregulare from hyphal swelling to spore maturity and found that the spores reached mature size within 30 to 60 days, and that the number of nuclei per spores increased over time. We conclude that the spores used for dispersal of AMF contain nuclei with two origins, those that migrate into the spore and those that arise by mitosis in the spore. Therefore, these spores do not represent a stage in the life cycle with a single nucleus, raising the possibility that AMF, unlike all other known eukaryotic organisms, lack the genetic bottleneck of a single-nucleus stage.

Reproductive skew drives patterns of sexual dimorphism in sponge-dwelling snapping shrimps

PubMed Central

Chak, Solomon Tin Chi; Duffy, J. Emmett; Rubenstein, Dustin R.

2015-01-01

Sexual dimorphism is typically a result of strong sexual selection on male traits used in male–male competition and subsequent female choice. However, in social species where reproduction is monopolized by one or a few individuals in a group, selection on secondary sexual characteristics may be strong in both sexes. Indeed, sexual dimorphism is reduced in many cooperatively breeding vertebrates and eusocial insects with totipotent workers, presumably because of increased selection on female traits. Here, we examined the relationship between sexual dimorphism and sociality in eight species of Synalpheus snapping shrimps that vary in social structure and degree of reproductive skew. In species where reproduction was shared more equitably, most members of both sexes were physiologically capable of breeding. However, in species where reproduction was monopolized by a single individual, a large proportion of females—but not males—were reproductively inactive, suggesting stronger reproductive suppression and conflict among females. Moreover, as skew increased across species, proportional size of the major chela—the primary antagonistic weapon in snapping shrimps—increased among females and sexual dimorphism in major chela size declined. Thus, as reproductive skew increases among Synalpheus, female–female competition over reproduction appears to increase, resulting in decreased sexual dimorphism in weapon size. PMID:26041357

Cope's Rule and the Universal Scaling Law of Ornament Complexity.

PubMed

Raia, Pasquale; Passaro, Federico; Carotenuto, Francesco; Maiorino, Leonardo; Piras, Paolo; Teresi, Luciano; Meiri, Shai; Itescu, Yuval; Novosolov, Maria; Baiano, Mattia Antonio; Martínez, Ricard; Fortelius, Mikael

2015-08-01

Luxuriant, bushy antlers, bizarre crests, and huge, twisting horns and tusks are conventionally understood as products of sexual selection. This view stems from both direct observation and from the empirical finding that the size of these structures grows faster than body size (i.e., ornament size shows positive allometry). We contend that the familiar evolutionary increase in the complexity of ornaments over time in many animal clades is decoupled from ornament size evolution. Increased body size comes with extended growth. Since growth scales to the quarter power of body size, we predicted that ornament complexity should scale according to the quarter power law as well, irrespective of the role of sexual selection in the evolution and function of the ornament. To test this hypothesis, we selected three clades (ammonites, deer, and ceratopsian dinosaurs) whose species bore ornaments that differ in terms of the importance of sexual selection to their evolution. We found that the exponent of the regression of ornament complexity to body size is the same for the three groups and is statistically indistinguishable from 0.25. We suggest that the evolution of ornament complexity is a by-product of Cope's rule. We argue that although sexual selection may control size in most ornaments, it does not influence their shape.

Ontogenetic shape changes and sexual dimorphism in Aegla marginata Bond-Buckup and Buckup, 1994.

PubMed

Adam, Carolina L; Marochi, Murilo Z; Masunari, Setuko

2018-05-14

A study on relative growth, sexual dimorphism and ontogenetic trajectory was carried out in a population of the aeglidAegla marginata coming from Barrinha River, Iguape River Basin, Tunas do Paraná, Paraná State, Brazil. The size the of morphological sexual maturity was estimated for males and females. The analysis of sexual dimorphism and ontogenetic trajectory were performed using geometric morphometric technique. Males reach maturity with 10.58 mm of carapace length (CL) and females with 10.38 mm CL. Sexual size dimorphism was only visible among adults, with males reaching larger sizes. This is probably related to the reproductive strategy of males. However, sexual shape dimorphism was found for both juveniles and adults: the posterior region of the carapace was wider in females. As the contrast of this feature was stronger in adults, it can be considered that large abdomen is advantageous for egg incubation. The allometric trajectories of juveniles presented similar directions, becoming divergent during the adult phase. The shape variation inA. marginataoccurred gradually throughout its development, with no abrupt transformation upon reaching sexual maturity. The reproductive adaptation is the main reason for the morphological variation within populations ofA. marginata.

Analysis of Biophysical Mechanisms of Gilgai Microrelief Formation in Dryland Swelling Soils Using Ultra-High Resolution Aerial Imagery

NASA Astrophysics Data System (ADS)

Krell, N.; DeCarlo, K. F.; Caylor, K. K.

2015-12-01

Microrelief formations ("gilgai"), which form due to successive wetting-drying cycles typical of swelling soils, provide ecological hotspots for local fauna and flora, including higher and more robust vegetative growth. The distribution of these gilgai suggests a remarkable degree of regularity. However, it is unclear to what extent the mechanisms that drive gilgai formation are physical, such as desiccation-induced fracturing, or biological in nature, namely antecedent vegetative clustering. We investigated gilgai genesis and pattern formation in a 100 x 100 meter study area with swelling soils in a semiarid grassland at the Mpala Research Center in central Kenya. Our ongoing experiment is composed of three 9m2 treatments: we removed gilgai and limited vegetative growth by herbicide application in one plot, allowed for unrestricted seed dispersal in another, and left gilgai unobstructed in a control plot. To estimate the spatial frequencies of the repeating patterns of gilgai, we obtained ultra-high resolution (0.01-0.03m/pixel) images with an unmanned aerial vehicle (UAV) from which digital elevation models were also generated. Geostatistical analyses using wavelet and fourier methods in 1- and 2-dimensions were employed to characterize gilgai size and distribution. Preliminary results support regular spatial patterning across the gilgaied landscape and heterogeneities may be related to local soil properties and biophysical influences. Local data on gilgai and fracture characteristics suggest that gilgai form at characteristic heights and spacing based on fracture morphology: deep, wide cracks result in large, highly vegetated mounds whereas shallow cracks, induced by animal trails, are less correlated with gilgai size and shape. Our experiments will help elucidate the links between shrink-swell processes and gilgai-vegetation patterning in high activity clay soils and advance our understanding of the mechanisms of gilgai formation in drylands.

Macromolecular 'size' and 'hardness' drives structure in solvent-swollen blends of linear, cyclic, and star polymers.

PubMed

Gartner, Thomas E; Jayaraman, Arthi

2018-01-17

In this paper, we apply molecular simulation and liquid state theory to uncover the structure and thermodynamics of homopolymer blends of the same chemistry and varying chain architecture in the presence of explicit solvent species. We use hybrid Monte Carlo (MC)/molecular dynamics (MD) simulations in the Gibbs ensemble to study the swelling of ∼12 000 g mol -1 linear, cyclic, and 4-arm star polystyrene chains in toluene. Our simulations show that the macroscopic swelling response is indistinguishable between the various architectures and matches published experimental data for the solvent annealing of linear polystyrene by toluene vapor. We then use standard MD simulations in the NPT ensemble along with polymer reference interaction site model (PRISM) theory to calculate effective polymer-solvent and polymer-polymer Flory-Huggins interaction parameters (χ eff ) in these systems. As seen in the macroscopic swelling results, there are no significant differences in the polymer-solvent and polymer-polymer χ eff between the various architectures. Despite similar macroscopic swelling and effective interaction parameters between various architectures, the pair correlation function between chain centers-of-mass indicates stronger correlations between cyclic or star chains in the linear-cyclic blends and linear-star blends, compared to linear chain-linear chain correlations. Furthermore, we note striking similarities in the chain-level correlations and the radius of gyration of cyclic and 4-arm star architectures of identical molecular weight. Our results indicate that the cyclic and star chains are 'smaller' and 'harder' than their linear counterparts, and through comparison with MD simulations of blends of soft spheres with varying hardness and size we suggest that these macromolecular characteristics are the source of the stronger cyclic-cyclic and star-star correlations.

Expansive focal cemento-osseous dysplasia.

PubMed

Bulut, Emel Uzun; Acikgoz, Aydan; Ozan, Bora; Zengin, Ayse Zeynep; Gunhan, Omer

2012-01-01

To present a case of expansive focal cemento-osseous dysplasia and emphasize the importance of differential diagnosis. Cemento-osseous dysplasia is categorized into three subtypes on the basis of the clinical and radiographic features: Periapical, focal and florid. The focal type exhibits a single site of involvement in any tooth-bearing or edentulous area of the jaws. These lesions are usually asymptomatic; therefore, they are frequently diagnosed incidentally during routine radiographic examinations. Lesions are usually benign, show limited growth, and do not require further surgical intervention, but periodic follow-up is recommended because occasionally, this type of dysplasia progresses into florid osseous dysplasia and simple bone cysts are formed. A 24-year-old female patient was referred to our clinic for swelling in the left edentulous mandibular premolarmolar region and felt discomfort when she wore her prosthetics. She had no pain, tenderness or paresthesia. Clinical examination showed that the swelling in the posterior mandible that was firm, nonfluctuant and covered by normal mucosa. On panoramic radiography and computed tomography, a well defined lesion of approximately 1.5 cm in diameter of mixed density was observed. The swelling increased slightly in size over 2 years making it difficult to use prosthetics and, therefore, the lesion was totally excised under local anesthesia, and surgical specimens were submitted for histopathological examination. The histopathological diagnosis was focal cemento-osseous dysplasia. In the present case, because of the increasing size of the swelling making it difficult to use prosthetics, young age of the patient and localization of the lesion, in the initial examination, cemento-ossifying fibroma was suspected, and the lesion was excised surgically; the histopathological diagnosis confirmed it as focal cemento-osseous dysplasia. We present a case of expansive focal cemento-osseous dysplasia. Differential diagnosis is essential because ossifying fibroma is a real neoplastic entity.

Sex While Intoxicated: A Meta-Analysis Comparing Heterosexual and Sexual Minority Youth

PubMed Central

Herrick, Amy L.; Marshal, Michael P.; Smith, Helen A.; Sucato, Gina; Stall, Ron D.

2013-01-01

Background The social marginalization and victimization experienced by sexual minority youth (SMY) may lead to increased risk behaviors and higher rates of negative health outcomes compared with their heterosexual peers. Methods We conducted a meta-analysis to examine whether SMY reported higher rates of sex while intoxicated. Studies that report rates of substance use during sex in both SMY and heterosexual youth and had a mean participant age of 18 or less were included in our meta-analysis. Effect sizes were extracted from six studies (nine independent data sets and 24 effect sizes) that met study criteria and had high inter-rater reliability (.98). Results Results indicated that SMY were almost twice as likely to report sex while intoxicated as compared with heterosexual peers. A random-effects meta-analysis showed a moderate ([overall weighted effect OR]= 1.91, p < .0001) weighted effect size for the relationship between sexual orientation and the use of drugs at the time of sexual intercourse, with the mean effect size for each study ranging from 1.21 to 3.50 and individual effect sizes ranging from .35 to 9.86. Discussion Our findings highlight the need for healthcare providers to screen SMY for participation in substance use during sexual intercourse and to offer risk reduction counseling during office visits. PMID:21338904

Modeling the Pore Formation Mechanism in UMo/AL Dispersion Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Yeon Soo; Jamison, L.; Hofman, G.

In UMo/Al dispersion fuel meat, pores formed in the ILs or at IL-Al interfaces tend to increase in size with irradiation, potentially limiting performance of this fuel. There has been no universally accepted mechanism for the formation and growth of this type of pore. However, there is a consensus that the stress state determined by meat swelling and fission- induced creep is one of the determinants, and fission gas availability at the pore site is another. Five dispersion RERTR miniplates that have well defined irradiation conditions and PIE data were selected for examination. Meat swelling and pore volume were measuredmore » in each plate. ABAQUS finite element analysis (FEA) package was utilized to obtain the time-dependent evolution of mechanical states in the plates while matching the measured meat swelling and creep. Interpretation of these results give insights on how to model a failure function – a predictor for large pore formation – using variables such as meat swelling, interaction layer growth, stress, and creep. This model can be used for optimizing fuel design parameters to reach the desired goal: meeting high power and performance reactor demand.« less

Deflate-gate: Conservative Management of a Large Ruptured Hydrocele

PubMed Central

Flores, Viktor X.; Wallen, Jared J.; Martinez, Danny R.; Carrion, Rafael

2015-01-01

A hydrocele is a common cause of intrascrotal swelling that results when fluid accumulates between the parietal and visceral layers of the tunica vaginalis. Over time, fluid may collect to form a massive hydrocele and result in significant discomfort for the patient. In this case report, we present a rare event of a 28-year-old gentleman with a documented massive hydrocele measuring 14.1 × 8.9 cm who ruptured his hydrocele during sexual intercourse. We expectantly managed the patient's ruptured hydrocele and encountered no complications throughout the course of his recovery. PMID:26793551

Current Treatment Options for Penile Fractures

PubMed Central

Jack, Gregory S; Garraway, Isla; Reznichek, Richard; Rajfer, Jacob

2004-01-01

The diagnosis of “penile fracture” describes the traumatic rupture of the tunica albuginea of an erect penis. Penile fractures typically occur when the engorged penile corpora are forced to buckle and literally “pop” under the pressure of a blunt sexual trauma. Patients typically describe immediate detumescence, severe pain, and swelling as a result of the injury. Prompt surgical exploration and corporal repair is the most efficacious therapy. Although a majority of cases can be diagnosed from the history and physical examination alone, radiographic studies, including retrograde urethrography and corporal cavernosography can aid in the diagnosis of unusual cases. PMID:16985591

Forgotten but Not Gone! Syphilis Induced Tenosynovitis.

PubMed

Ratnaraj, Felicia; Brooks, David; Walton, Mollie; Nagabandi, Arun; Abu Hazeem, Mahmoud

2016-01-01

Objective . Tenosynovitis, inflammation of a tendon and its synovial sheath, is a rare manifestation of secondary syphilis and if diagnosed early is reversible. Background . A 52-year-old male with past medical history of untreated syphilis presented with gradual onset of swelling and pain of the right fourth metacarpophalangeal joint (MCP). He reported a history of painless penile lesions after having sexual intercourse with a new partner approximately five months ago which was treated with sulfamethoxazole/trimethoprim. An RPR done at that time came back positive with a high titer; however, patient was lost to follow-up. On examination, patient had an edematous, nonerythematous right fourth proximal interphalangeal (PIP) joint. Urgent irrigation, debridement, and exploration of the right hand into the tendon sheath were performed. With his history of syphillis, an RPR was done, which was reactive with a titer of 1 : 64. A confirmatory FTA-ABS test was completed, rendering a positive result. Based on his history of untreated syphilis, dormancy followed by clinical scenario of swelling of the right fourth finger, and a high RPR titer, he was diagnosed with secondary syphilis manifesting as tenosynovitis.

Forgotten but Not Gone! Syphilis Induced Tenosynovitis

PubMed Central

Brooks, David; Walton, Mollie; Nagabandi, Arun

2016-01-01

Objective. Tenosynovitis, inflammation of a tendon and its synovial sheath, is a rare manifestation of secondary syphilis and if diagnosed early is reversible. Background. A 52-year-old male with past medical history of untreated syphilis presented with gradual onset of swelling and pain of the right fourth metacarpophalangeal joint (MCP). He reported a history of painless penile lesions after having sexual intercourse with a new partner approximately five months ago which was treated with sulfamethoxazole/trimethoprim. An RPR done at that time came back positive with a high titer; however, patient was lost to follow-up. On examination, patient had an edematous, nonerythematous right fourth proximal interphalangeal (PIP) joint. Urgent irrigation, debridement, and exploration of the right hand into the tendon sheath were performed. With his history of syphillis, an RPR was done, which was reactive with a titer of 1 : 64. A confirmatory FTA-ABS test was completed, rendering a positive result. Based on his history of untreated syphilis, dormancy followed by clinical scenario of swelling of the right fourth finger, and a high RPR titer, he was diagnosed with secondary syphilis manifesting as tenosynovitis. PMID:28050292

Meta-analysis of studies assessing the efficacy of projective techniques in discriminating child sexual abuse.

PubMed

West, M M

1998-11-01

This meta-analysis of 12 studies assesses the efficacy of projective techniques to discriminate between sexually abused children and nonsexually abused children. A literature search was conducted to identify published studies that used projective instruments with sexually abused children. Those studies that reported statistics that allowed for an effect size to be calculated, were then included in the meta-analysis. There were 12 studies that fit the criteria. The projectives reviewed include The Rorschach, The Hand Test, The Thematic Apperception Test (TAT), the Kinetic Family Drawings, Human Figure Drawings, Draw Your Favorite Kind of Day, The Rosebush: A Visualization Strategy, and The House-Tree-Person. The results of this analysis gave an over-all effect size of d = .81, which is a large effect. Six studies included only a norm group of nondistressed, nonabused children with the sexual abuse group. The average effect size was d = .87, which is impressive. Six studies did include a clinical group of distressed nonsexually abused subjects and the effect size lowered to d = .76, which is a medium to large effect. This indicates that projective instruments can discriminate distressed children from nondistressed subjects, quite well. In the studies that included a clinical group of distressed children who were not sexually abused, the lower effect size indicates that the instruments were less able to discriminate the type of distress. This meta-analysis gives evidence that projective techniques have the ability to discriminate between children who have been sexually abused and those who were not abused sexually. However, further research that is designed to include clinical groups of distressed children is needed in order to determine how well the projectives can discriminate the type of distress.

Effect Size in Efficacy Trials of Women With Decreased Sexual Desire.

PubMed

Pyke, Robert E; Clayton, Anita H

2018-03-22

Regarding hypoactive sexual desire disorder (HSDD) in women, some reviewers judge the effect size small for medications vs placebo, but substantial for cognitive behavior therapy (CBT) or mindfulness meditation training (MMT) vs wait list. However, we lack comparisons of the effect sizes for the active intervention itself, for the control treatment, and for the differential between the two. For efficacy trials of HSDD in women, compare effect sizes for medications (testosterone/testosterone transdermal system, flibanserin, and bremelanotide) and placebo vs effect sizes for psychotherapy and wait-list control. We conducted a literature search for mean changes and SD on main measures of sexual desire and associated distress in trials of medications, CBT, or MMT. Effect size was used as it measures the magnitude of the intervention without confounding by sample size. Cohen d was used to determine effect sizes. For medications, mean (SD) effect size was 1.0 (0.34); for CBT and MMT, 1.0 (0.36); for placebo, 0.55 (0.16); and for wait list, 0.05 (0.26). Recommendations of psychotherapy over medication for treatment of HSDD are premature and not supported by data on effect sizes. Active participation in treatment conveys considerable non-specific benefits. Caregivers should attend to biological and psychosocial elements, and patient preference, to optimize response. Few clinical trials of psychotherapies were substantial in size or utilized adequate control paradigms. Medications and psychotherapies had similar, large effect sizes. Effect size of placebo was moderate. Effect size of wait-list control was very small, about one quarter that of placebo. Thus, a substantial non-specific therapeutic effect is associated with receiving placebo plus active care and evaluation. The difference in effect size between placebo and wait-list controls distorts the value of the subtraction of effect of the control paradigms to estimate intervention effectiveness. Pyke RE, Clayton AH. Effect Size in Efficacy Trials of Women With Decreased Sexual Desire. Sex Med Rev 2018;XX:XXX-XXX. Copyright © 2018 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Surface facial modelling and allometry in relation to sexual dimorphism.

PubMed

Velemínská, J; Bigoni, L; Krajíček, V; Borský, J; Šmahelová, D; Cagáňová, V; Peterka, M

2012-04-01

Sexual dimorphism is responsible for a substantial part of human facial variability, the study of which is essential for many scientific fields ranging from evolution to special biomedical topics. Our aim was to analyse the relationship between size variability and shape facial variability of sexual traits in the young adult Central European population and to construct average surface models of adult males and females. The method of geometric morphometrics allowed not only the identification of dimorphic traits, but also the evaluation of static allometry and the visualisation of sexual facial differences. Facial variability in the studied sample was characterised by a strong relationship between facial size and shape of sexual dimorphic traits. Large size of face was associated with facial elongation and vice versa. Regarding shape sexual dimorphic traits, a wide, vaulted and high forehead in combination with a narrow and gracile lower face were typical for females. Variability in shape dimorphic traits was smaller in females compared to males. For female classification, shape sexual dimorphic traits are more important, while for males the stronger association is with face size. Males generally had a closer inter-orbital distance and a deeper position of the eyes in relation to the facial plane, a larger and wider straight nose and nostrils, and more massive lower face. Using pseudo-colour maps to provide a detailed schematic representation of the geometrical differences between the sexes, we attempted to clarify the reasons underlying the development of such differences. Copyright © 2012 Elsevier GmbH. All rights reserved.

Intra- and Trans-Generational Costs of Reduced Female Body Size Caused by Food Limitation Early in Life in Mites

PubMed Central

Walzer, Andreas; Schausberger, Peter

2013-01-01

Background Food limitation early in life may be compensated for by developmental plasticity resulting in accelerated development enhancing survival at the expense of small adult body size. However and especially for females in non-matching maternal and offspring environments, being smaller than the standard may incur considerable intra- and trans-generational costs. Methodology/Principal Findings Here, we evaluated the costs of small female body size induced by food limitation early in life in the sexually size-dimorphic predatory mite Phytoseiulus persimilis. Females are larger than males. These predators are adapted to exploit ephemeral spider mite prey patches. The intra- and trans-generational effects of small maternal body size manifested in lower maternal survival probabilities, decreased attractiveness for males, and a reduced number and size of eggs compared to standard-sized females. The trans-generational effects of small maternal body size were sex-specific with small mothers producing small daughters but standard-sized sons. Conclusions/Significance Small female body size apparently intensified the well-known costs of sexual activity because mortality of small but not standard-sized females mainly occurred shortly after mating. The disadvantages of small females in mating and egg production may be generally explained by size-associated morphological and physiological constraints. Additionally, size-assortative mate preferences of standard-sized mates may have rendered small females disproportionally unattractive mating partners. We argue that the sex-specific trans-generational effects were due to sexual size dimorphism – females are the larger sex and thus more strongly affected by maternal stress than the smaller males – and to sexually selected lower plasticity of male body size. PMID:24265745

Female sexual function and the clitoral complex using pelvic MRI assessment.

PubMed

Vaccaro, Christine M; Fellner, Angela N; Pauls, Rachel N

2014-09-01

To report basic measurements of clitoral anatomy, and explore potential relationships between the clitoral complex and female sexual function using MRI assessment. In this retrospective descriptive study, 20 sexually active women (≥18 years) who had a recent pelvic MRI for various gynecologic concerns were invited to participate. Outcome measures included demographic data, medical and sexual history, quality of life questionnaires: Female Sexual Function Index (FSFI), Body Exposure during Sexual Activities Questionnaire (BESAQ), and Short Form Quality of Life Questionnaire (SF-12). These data were then compared to detailed clitoral MRI measurements and analyzed using the Pearson correlation and Chi square test. FSFI domains of desire, arousal, lubrication, and orgasm were inversely correlated with clitoral size (p=0.01-0.04), as were SF-12 physical composite scores (p=0.003), suggesting improved sexual function and physical health in women with smaller clitoral structures (specifically the clitoral body and crus). Sexual function was improved in women with a smaller-sized clitoris, specifically the clitoral body and crus. Published by Elsevier Ireland Ltd.

Electrical Sensing Zone Particle Analyzer for Measuring Germination of Fungal Spores in the Presence of Other Particles1

PubMed Central

Santoro, T.; Stotzky, G.; Rem, L. T.

1967-01-01

Microscopic, respirometric, and electronic sizing methods for measuring germination of fungal spores were compared. With the electronic sizing method, early stages of germination (i.e., spore swelling) were detected long before germ tube emergence or significant changes in respiratory rates were observed. This method, which is rapid, easy, sensitive, and reproducible, also permits measuring the germination of spores when similar-size particles are present in concentrations considerably in excess of the number of spores. PMID:6069161

Correlational selection leads to genetic integration of body size and an attractive plumage trait in dark-eyed juncos.

PubMed

McGlothlin, Joel W; Parker, Patricia G; Nolan, Val; Ketterson, Ellen D

2005-03-01

When a trait's effect on fitness depends on its interaction with other traits, the resultant selection is correlational and may lead to the integration of functionally related traits. In relation to sexual selection, when an ornamental trait interacts with phenotypic quality to determine mating success, correlational sexual selection should generate genetic correlations between the ornament and quality, leading to the evolution of honest signals. Despite its potential importance in the evolution of signal honesty, correlational sexual selection has rarely been measured in natural populations. In the dark-eyed junco (Junco hyemalis), males with experimentally elevated values of a plumage trait (whiteness in the tail or "tail white") are more attractive to females and dominant in aggressive encounters over resources. We used restricted maximum-likelihood analysis of a long-term dataset to measure the heritability of tail white and two components of body size (wing length and tail length), as well as genetic correlations between pairs of these traits. We then used multiple regression to assess directional, quadratic, and correlational selection as they acted on tail white and body size via four components of lifetime fitness (juvenile and adult survival, mating success, and fecundity). We found a positive genetic correlation between tail white and body size (as measured by wing length), which indicates past correlational selection. Correlational selection, which was largely due to sexual selection on males, was also found to be currently acting on the same pair of traits. Larger males with whiter tails sired young with more females, most likely due to a combination of female choice, which favors males with whiter tails, and male-male competition, which favors both tail white and larger body size. To our knowledge, this is the first study to show both genetic correlations between sexually selected traits and currently acting correlational sexual selection, and we suggest that correlational sexual selection frequently may be an important mechanism for maintaining the honesty of sexual signals.

Alternative life histories in Xiphophorus multilineatus: evidence for different ages at sexual maturity and growth responses in the wild.

PubMed

Bono, L M; Rios-Cardenas, O; Morris, M R

2011-05-01

In order to examine potential trade-offs in alternative life histories of the high-backed pygmy swordtail Xiphophorus multilineatus, otoliths were used from wild-caught males to determine if sneaker males had the advantage of maturing earlier in natural environments. The sneakers matured significantly earlier than courters, but there was no difference among the three courter variants. In addition, analyses suggested that the effect of the pituitary locus on size at sexual maturity and growth rates was a consequence of age at sexual maturity. Finally, one of the courter variants had a significantly different relationship between age and size at sexual maturity than the other variants, suggesting that in this variant, age at sexual maturity may be more closely related to size and therefore may be less plastic in its growth responses. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Controlling the extrudate swell in melt extrusion additive manufacturing of 3D scaffolds: a designed experiment.

PubMed

Yousefi, Azizeh-Mitra; Smucker, Byran; Naber, Alex; Wyrick, Cara; Shaw, Charles; Bennett, Katelyn; Szekely, Sarah; Focke, Carlie; Wood, Katherine A

2018-02-01

Tissue engineering using three-dimensional porous scaffolds has shown promise for the restoration of normal function in injured and diseased tissues and organs. Rigorous control over scaffold architecture in melt extrusion additive manufacturing is highly restricted mainly due to pronounced variations in the deposited strand diameter upon any variations in process conditions and polymer viscoelasticity. We have designed an I-optimal, split-plot experiment to study the extrudate swell in melt extrusion additive manufacturing and to control the scaffold architecture. The designed experiment was used to generate data to relate three responses (swell, density, and modulus) to a set of controllable factors (plotting needle diameter, temperature, pressure, and the dispensing speed). The fitted regression relationships were used to optimize the three responses simultaneously. The swell response was constrained to be close to 1 while maximizing the modulus and minimizing the density. Constraining the extrudate swell to 1 generates design-driven scaffolds, with strand diameters equal to the plotting needle diameter, and allows a greater control over scaffold pore size. Hence, the modulus of the scaffolds can be fully controlled by adjusting the in-plane distance between the deposited strands. To the extent of the model's validity, we can eliminate the effect of extrudate swell in designing these scaffolds, while targeting a range of porosity and modulus appropriate for bone tissue engineering. The result of this optimization was a predicted modulus of 14 MPa and a predicted density of 0.29 g/cm 3 (porosity ≈ 75%) using polycaprolactone as scaffold material. These predicted responses corresponded to factor levels of 0.6 μm for the plotting needle diameter, plotting pressure of 2.5 bar, melt temperature of 113.5 °C, and dispensing speed of 2 mm/s. The validation scaffold enabled us to quantify the percentage difference for the predictions, which was 9.5% for the extrudate swell, 19% for the density, and 29% for the modulus.

Swelling/Floating Capability and Drug Release Characterizations of Gastroretentive Drug Delivery System Based on a Combination of Hydroxyethyl Cellulose and Sodium Carboxymethyl Cellulose

PubMed Central

Chen, Ying-Chen; Ho, Hsiu-O; Liu, Der-Zen; Siow, Wen-Shian; Sheu, Ming-Thau

2015-01-01

The aim of this study was to characterize the swelling and floating behaviors of gastroretentive drug delivery system (GRDDS) composed of hydroxyethyl cellulose (HEC) and sodium carboxymethyl cellulose (NaCMC) and to optimize HEC/NaCMC GRDDS to incorporate three model drugs with different solubilities (metformin, ciprofloxacin, and esomeprazole). Various ratios of NaCMC to HEC were formulated, and their swelling and floating behaviors were characterized. Influences of media containing various NaCl concentrations on the swelling and floating behaviors and drug solubility were also characterized. Finally, release profiles of the three model drugs from GRDDS formulation (F1-4) and formulation (F1-1) were examined. Results demonstrated when the GRDDS tablets were tested in simulated gastric solution, the degree of swelling at 6 h was decreased for each formulation that contained NaCMC in comparison to those in de-ionized water (DIW). Of note, floating duration was enhanced when in simulated gastric solution compared to DIW. Further, the hydration of tablets was found to be retarded as the NaCl concentration in the medium increased resulting in smaller gel layers and swelling sizes. Dissolution profiles of the three model drugs in media containing various concentrations of NaCl showed that the addition of NaCl to the media affected the solubility of the drugs, and also their gelling behaviors, resulting in different mechanisms for controlling a drug’s release. The release mechanism of the freely water-soluble drug, metformin, was mainly diffusion-controlled, while those of the water-soluble drug, ciprofloxacin, and the slightly water-soluble drug, esomeprazole, were mainly anomalous diffusion. Overall results showed that the developed GRDDS composed of HEC 250HHX and NaCMC of 450 cps possessed proper swelling extents and desired floating periods with sustained-release characteristics. PMID:25617891

pH-Sensitive breathing of clay within the polyelectrolyte matrix.

PubMed

Chaturbedy, Piyush; Jagadeesan, Dinesh; Eswaramoorthy, Muthusamy

2010-10-26

Stimuli-responsive organic-inorganic hybrid spheres were synthesized by coating the colloidal polystyrene spheres with polyelectrolyte-protected aminoclay, Mg phyllo(organo)silicate layers in a layer-by-layer method. The clay layers are sandwiched between the polyelectrolyte layers. The aminoclay swells in water due to protonation of amino groups, and the degree of swelling depends on the pH of the medium. As a result, the hybrid spheres undergo a size change up to 60% as the pH is changed from 9 to 4. The stimuli-responsive property of the hybrid spheres was used for the release of ibuprofen and eosin at different pH.

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

PubMed Central

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-01-01

Introduction Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. Aim To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. Methods An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). Main Outcome Measures The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Results Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Conclusion Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures. PMID:26468378

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-09-01

Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures.

Mesoporous block-copolymer nanospheres prepared by selective swelling.

PubMed

Mei, Shilin; Jin, Zhaoxia

2013-01-28

Block-copolymer (BCP) nanospheres with hierarchical inner structure are of great interest and importance due to their possible applications in nanotechnology and biomedical engineering. Mesoporous BCP nanospheres with multilayered inner channels are considered as potential drug-delivery systems and templates for multifunctional nanomaterials. Selective swelling is a facile pore-making strategy for BCP materials. Herein, the selective swelling-induced reconstruction of BCP nanospheres is reported. Two poly(styrene-block-2-vinylpyridine) (PS-b-P2VP) samples with different compositions (PS(23600)-b-P2VP(10400) and PS(27700)-b-P2VP(4300)) are used as model systems. The swelling reconstruction of PS-b-P2VP in ethanol, 1-pyrenebutyric acid (PBA)/ethanol, or HCl/ethanol (pH = 2.61) is characterized by scanning electron microscopy and transmission electron microscopy. It is observed that the length of the swellable block in BCP is a critical factor in determining the behavior and nanostructures of mesoporous BCP nanospheres in selective swelling. Moreover, it is demonstrated that the addition of PBA modifies the swelling structure of PS(23600)-b-P2VP(10400) through the interaction between PBA and P2VP blocks, which results in BCP nanospheres with patterned pores of controllable size. The patterned pores can be reversibly closed by annealing the mesoporous BCP nanospheres in different selective solvents. The controllable and reversible open/closed reconstruction of BCP nanospheres can be used to enclose functional nanoparticles or drugs inside the nanospheres. These mesoporous BCP nanospheres are further decorated with gold nanoparticles by UV photoreduction. The enlarged decoration area in mesoporous BCP nanospheres will enhance their activity and sensitivity as a catalyst and electrochemical sensor. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reproductive and resource benefits to large female body size in a mammal with female-biased sexual size dimorphism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fokidis, H.B., T.S. Risch and T.C. Glenn

Factors underlying the evolution of female-biased sexual size dimorphism in mammals are poorly understood. In an effort to better understand these factors we tested whether larger female southern flying squirrels, Glaucomys volans, gained reproductive advantages (larger litters or more male mates) and direct resource benefits, such as larger home ranges or access to more food (i.e. mast-producing trees). As dimorphism can vary with age in precocial breeding species, we compared females during their first reproduction and during a subsequent breeding attempt. Females were not significantly larger or heavier than males at first reproduction, but became about 7% heavier and 22%more » larger than males at subsequent breeding. Larger females produced larger litters and had home ranges containing a greater proportion of upland hardwood trees. Female body size was not associated with either multiple male mating or home range size, but females with larger home ranges had higher indexes of body condition. Females in precocial breeding flying squirrels initiate reproduction before sexual size dimorphism is evident, and thus, may be allocating resources to both reproduction and growth simultaneously, or delaying growth entirely. Larger females produce more pups and have access to more food resources. Thus, selection for increased female size may partly explain how female-biased sexual size dimorphism is maintained in this species.« less

Patterns of sexual size dimorphism in horseshoe bats: Testing Rensch's rule and potential causes.

PubMed

Wu, Hui; Jiang, Tinglei; Huang, Xiaobin; Feng, Jiang

2018-02-08

Rensch's rule, stating that sexual size dimorphism (SSD) becomes more evident and male-biased with increasing body size, has been well supported for taxa that exhibit male-biased SSD. Bats, primarily having female-biased SSD, have so far been tested for whether SSD allometry conforms to Rensch's rule in only three studies. However, these studies did not consider phylogeny, and thus the mechanisms underlying SSD variations in bats remain unclear. Thus, the present study reviewed published and original data, including body size, baculum size, and habitat types in 45 bats of the family Rhinolophidae to determine whether horseshoe bats follow Rensch's rule using a phylogenetic comparative framework. We also investigated the potential effect of postcopulatory sexual selection and habitat type on SSD. Our findings indicated that Rensch's rule did not apply to Rhinolophidae, suggesting that SSD did not significantly vary with increasing size. This pattern may be attributable interactions between weak sexual selection to male body size and strong fecundity selection for on female body size. The degree of SSD among horseshoe bats may be attributed to a phylogenetic effect rather than to the intersexual competition for food or to baculum length. Interestingly, we observed that species in open habitats exhibited greater SSD than those in dense forests, suggesting that habitat types may be associated with variations in SSD in horseshoe bats.

Self-assessment of anatomy, sexual sensitivity, and function of the labia and vagina.

PubMed

Schober, Justine M; Alguacil, Nieves Martin; Cooper, R Scott; Pfaff, Donald W; Meyer-Bahlburg, Heino F L

2015-04-01

Patient perceptions of genital esthetics are motivating requests for plastic surgeries that could change sexual sensitivity. There is little information about the sensitivities of labial and introital sites. The aim of this study is to assess the relationship between sexual sensitivity and self-reported sizes of labial and introital sites. Sixty-two healthy, sexually active, adult women (mean age 37.9, range 21-60) with no history of genital or vaginal surgery gave written consent to participate in this study. A modified version of Self-Assessment of Genital Anatomy and Sexual Function (L-SAGASF-F) was used to assess labial and introital size. Site-specific sensation was rated on Likert scales of 1-5. Anatomical locations were compared for ratings. Of 62 responders, 84% (52) described their labia as "average-sized," 11% (7) described their labia minora and 13% (8) their labia majora as "large", and 3% (2) and 5% (3) as "small". Sexual pleasure ratings were "moderate" (median value: 3.0 for external genitalia and vaginal lumen) or "strong" (median value: 4.0 for the interior vagina). Significantly higher rankings related to the vaginal opening (P=0.007). Orgasm intensity for stimulation of the external genitalia progressively increased toward the vaginal opening, from 1.0 to 3.0 (P=0.001); vaginal ratings showed a similar progression, from 2.0 at the external luminal margin to 3.0 in the deep interior (P<0.0001). Orgasm effort scores were intermediate (median: 3.0), uniform throughout the external and internal areas (P=0.626). Ratings for labial and introital sensitivity, regardless of self-reported size, were very similar to those at other genital sites for sexual pleasure. Surgical excision of labial and introital structures could modify sexual sensation. © 2015 Wiley Periodicals, Inc.

Phenology of Scramble Polygyny in a Wild Population of Chrysolemid Beetles: The Opportunity for and the Strength of Sexual Selection

PubMed Central

Baena, Martha Lucía; Macías-Ordóñez, Rogelio

2012-01-01

Recent debate has highlighted the importance of estimating both the strength of sexual selection on phenotypic traits, and the opportunity for sexual selection. We describe seasonal fluctuations in mating dynamics of Leptinotarsa undecimlineata (Coleoptera: Chrysomelidae). We compared several estimates of the opportunity for, and the strength of, sexual selection and male precopulatory competition over the reproductive season. First, using a null model, we suggest that the ratio between observed values of the opportunity for sexual selections and their expected value under random mating results in unbiased estimates of the actual nonrandom mating behavior of the population. Second, we found that estimates for the whole reproductive season often misrepresent the actual value at any given time period. Third, mating differentials on male size and mobility, frequency of male fighting and three estimates of the opportunity for sexual selection provide contrasting but complementary information. More intense sexual selection associated to male mobility, but not to male size, was observed in periods with high opportunity for sexual selection and high frequency of male fights. Fourth, based on parameters of spatial and temporal aggregation of female receptivity, we describe the mating system of L. undecimlineata as a scramble mating polygyny in which the opportunity for sexual selection varies widely throughout the season, but the strength of sexual selection on male size remains fairly weak, while male mobility inversely covaries with mating success. We suggest that different estimates for the opportunity for, and intensity of, sexual selection should be applied in order to discriminate how different behavioral and demographic factors shape the reproductive dynamic of populations. PMID:22761675

Linking big five personality traits to sexuality and sexual health: A meta-analytic review.

PubMed

Allen, Mark S; Walter, Emma E

2018-06-07

This meta-analytic review addresses whether the major dimensions of trait personality relate to components of human sexuality. A comprehensive literature search identified 137 studies that met inclusion criteria (761 effect sizes; total n = 420,595). Pooled mean effects were computed using inverse-variance weighted random effects meta-analysis. Mean effect sizes from 100 separate meta-analyses provided evidence that personality relates to theoretically predicted components of sexuality and sexual health. Neuroticism was positively related to sexual dissatisfaction (r+ = .18), negative emotions (r+ = .42), and symptoms of sexual dysfunction (r+ = .16). Extraversion was positively related to sexual activity (r+ = .17) and risky sexual behavior (r+ = .18), and negatively related to symptoms of sexual dysfunction (r+ = -.17). Openness was positively related to homosexual orientation (r+ = .16) and liberal attitudes toward sex (r+ = .19). Agreeableness and conscientiousness were negatively related to sexually aggressive behavior (r+ = -.20; r+ = -.14) and sexual infidelity (r+ = -.18; r+ = -.17). Less robust evidence indicated that extraversion related negatively, and neuroticism positively, to child sexual abuse, and that openness related negatively to homophobic attitudes. Random effects metaregression identified age, gender, and study quality as important moderators of pooled mean effects. These findings might be of interest to health care professionals developing health care services that aim to promote sexually healthy societies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Effectiveness of Psychoeducational Interventions Focused on Sexuality in Cancer.

PubMed

Kim, Jung-Hee; Yang, Younghee; Hwang, Eun-Suk

2015-01-01

Although sexual health is a common concern for oncology patients, no practical guidelines to sexual intervention exist, perhaps because of a lack of systematic reviews or meta-analyses. The objectives of this study were to determine the effect size for psychoeducational intervention focused on sexuality and to compare effect sizes according to intervention outcomes and characteristic. We explored quantitative evidence for the effects of sexual intervention for cancer patients or partners by using the electronic databases. Among them, we considered 15 eligible articles. The meta-analysis provided 133 effect sizes from 15 primary studies. The analysis revealed significant improvements after intervention, with a random-effects standardized mean difference of 0.75. Psychoeducational interventions focused on sexuality after cancer diagnosis were effective for compliance (2.40), cognitive aspect (1.29), and psychological aspect (0.83). Individual-based interventions (0.85) were more effective in improving outcomes than group approach and group combined with individual intervention. With regard to intervention providers, registered nurse only (2.22) and team approach including the registered nurse (2.38) had the highest effect size. Face-to-face intervention combined with telephone or the Internet (1.04) demonstrated a higher effect size than face-to-face (0.62) and telephone (0.58) independently. We conducted an analysis of data from various subgroups of preexisting studies, obtained an overall estimate of the effectiveness of the intervention, and compared its effectiveness across variables that affect intervention outcomes. These results provide empirical data for evidence-based practice and inform the development of useful intervention programs through a comprehensive review and meta-analysis of the results.

Superporous polyacrylate/chitosan IPN hydrogels for protein delivery.

PubMed

Gümüşderelioğlu, Menemşe; Erce, Deniz; Demirtaş, T Tolga

2011-11-01

In this study, poly(acrylamide), poly(AAm), and poly(acrylamide-co-acrylic acid), poly(AAm-co-AA) superporous hydrogels (SPHs) were synthesized by radical polymerization in the presence of gas blowing agent, sodium bicarbonate. In addition, ionically crosslinked chitosan (CH) superporous hydrogels were synthesized to form interpenetrating superporous hydrogels, i.e. poly(AAm)-CH and poly(AAm-co-AA)-CH SPH-IPNs. The hydrogels have a structure of interconnected pores with pore sizes of approximately 100-150 μm. Although the extent of swelling increased when AA were incorporated to the poly(AAm) structure, the time to reach the equilibrium swelling (~30 s) was not affected so much. In the presence of chitosan network mechanical properties significantly improved when compared with SPHs, however, equilibrium swelling time (~30 min) was prolonged significantly as due to the lower porosities and pore sizes of SPH-IPNs than that of SPHs. Model protein bovine serum albumin (BSA) was loaded into SPHs and SPH-IPNs by solvent sorption in very short time (<1 h) and very high capacities (~30-300 mg BSA/g dry gel) when compared to conventional hydrogels. BSA release profiles from SPHs and SPH-IPNs were characterized by an initial burst of protein during the first 20 min followed by a completed release within 1 h. However, total releasable amount of BSA from SPH-IPNs was lower than that of SPHs as due to the electrostatic interactions between chitosan and BSA.

Counterion-induced swelling of ionic microgels

NASA Astrophysics Data System (ADS)

Denton, Alan R.; Tang, Qiyun

2016-10-01

Ionic microgel particles, when dispersed in a solvent, swell to equilibrium sizes that are governed by a balance between electrostatic and elastic forces. Tuning of particle size by varying external stimuli, such as pH, salt concentration, and temperature, has relevance for drug delivery, microfluidics, and filtration. To model swelling of ionic microgels, we derive a statistical mechanical theorem, which proves exact within the cell model, for the electrostatic contribution to the osmotic pressure inside a permeable colloidal macroion. Applying the theorem, we demonstrate how the distribution of counterions within an ionic microgel determines the internal osmotic pressure. By combining the electrostatic pressure, which we compute via both Poisson-Boltzmann theory and molecular dynamics simulation, with the elastic pressure, modeled via the Flory-Rehner theory of swollen polymer networks, we show how deswelling of ionic microgels with increasing concentration of particles can result from a redistribution of counterions that reduces electrostatic pressure. A linearized approximation for the electrostatic pressure, which proves remarkably accurate, provides physical insight and greatly eases numerical calculations for practical applications. Comparing with experiments, we explain why soft particles in deionized suspensions deswell upon increasing concentration and why this effect may be suppressed at higher ionic strength. The failure of the uniform ideal-gas approximation to adequately account for counterion-induced deswelling below close packing of microgels is attributed to neglect of spatial variation of the counterion density profile and the electrostatic pressure of incompletely neutralized macroions.

Chitosan-based hydrogel tissue scaffolds made by 3D plotting promotes osteoblast proliferation and mineralization.

PubMed

Liu, I-Hsin; Chang, Shih-Hsin; Lin, Hsin-Yi

2015-05-13

A 3D plotting system was used to make chitosan-based tissue scaffolds with interconnected pores using pure chitosan (C) and chitosan cross-linked with pectin (CP) and genipin (CG). A freeze-dried chitosan scaffold (CF/D) was made to compare with C, to observe the effects of structural differences. The fiber size, pore size, porosity, compression strength, swelling ratio, drug release efficacy, and cumulative weight loss of the scaffolds were measured. Osteoblasts were cultured on the scaffolds and their proliferation, type I collagen production, alkaline phosphatase activity, calcium deposition, and morphology were observed. C had a lower swelling ratio, degradation, porosity and drug release efficacy and a higher compressional stiffness and cell proliferation compared to CF/D (p < 0.05). Of the 3D-plotted samples, cells on CP exhibited the highest degree of mineralization after 21 d (p < 0.05). CP also had the highest swelling ratio and fastest drug release, followed by C and CG (p < 0.05). Both CP and CG were stiffer and degraded more slowly in saline solution than C (p < 0.05). In summary, 3D-plotted scaffolds were stronger, less likely to degrade and better promoted osteoblast cell proliferation in vitro compared to the freeze-dried scaffolds. C, CP and CG were structurally similar, and the different crosslinking caused significant changes in their physical and biological performances.

Wheat germ agglutinin-conjugated chitosan-Ca-alginate microparticles for local colon delivery of 5-FU: development and in vitro characterization.

PubMed

Glavas Dodov, M; Calis, S; Crcarevska, M S; Geskovski, N; Petrovska, V; Goracinova, K

2009-11-03

The aim of this work was to prepare lectin-conjugated chitosan-Ca-alginate microparticles (MPs) loaded with acid-resistant particles of 5-fluorouracil (5-FU) for efficient local treatment of colon cancer. MPs were prepared by a novel one-step spray-drying technique and after wheat germ agglutinin (WGA) conjugation, they were characterized for size, swelling behavior, surface charge, entrapment efficiency and in vitro drug release. Prepared particles were spherical, with 6.73 microg/mg of WGA conjugated onto their surface. The size and zeta potential increased after conjugation, from 6.6 to 14.7 microm and from 9.6 to 15.3 mV, while drug encapsulation was 75.6 and 72.8%, respectively after conjugation. The swelling behavior of beads was mainly determined by properties of the cross-linked chitosan-alginate network. In vitro drug release studies carried out in simulated in vivo conditions with respect to pH, confirmed the potential of the particles to release the drug in a controlled manner. Also, the drug release was not significantly affected by WGA conjugation. The retention of biorecognitive activity of WGA after covalent coupling to MPs was confirmed by haemagglutination test. Functionalized MPs showed excessive mucoadhesiveness in vitro, due to the positive surface charge, pH-dependent swelling of the matrix and lectin-sugar recognition.

Enhanced Radiation-tolerant Oxide Dispersion Strengthened Steel and its Microstructure Evolution under Helium-implantation and Heavy-ion Irradiation

PubMed Central

Lu, Chenyang; Lu, Zheng; Wang, Xu; Xie, Rui; Li, Zhengyuan; Higgins, Michael; Liu, Chunming; Gao, Fei; Wang, Lumin

2017-01-01

The world eagerly needs cleanly-generated electricity in the future. Fusion reactor is one of the most ideal energy resources to defeat the environmental degradation caused by the consumption of traditional fossil energy. To meet the design requirements of fusion reactor, the development of the structural materials which can sustain the elevated temperature, high helium concentration and extreme radiation environments is the biggest challenge for the entire material society. Oxide dispersion strengthened steel is one of the most popular candidate materials for the first wall/blanket applications in fusion reactor. In this paper, we evaluate the radiation tolerance of a 9Cr ODS steel developed in China. Compared with Ferritic/Martensitic steel, this ODS steel demonstrated a significantly higher swelling resistance under ion irradiation at 460 °C to 188 displacements per atom. The role of oxides and grain boundaries on void swelling has been explored. The results indicated that the distribution of higher density and finer size of nano oxides will lead a better swelling resistance for ODS alloy. The original pyrochlore-structured Y2Ti2O7 particles dissolved gradually while fine Y-Ti-O nano clusters reprecipitated in the matrix during irradiation. The enhanced radiation tolerance is attributed to the reduced oxide size and the increased oxide density. PMID:28079191

The effect of fragmentation on loader productivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGill, M.D.; Freadrich, J.

1994-12-31

There are many factors which affect the productivity of a front end loader. One of the most obvious is the characteristics of the material being mined. Characteristics such as size distribution, swell factor or heave, and material hardness/abrasiveness will all effect the efficiency of the mucking cycle. The focus of this paper is to look specifically at the size distribution of blasted material, and quantify the effects on loader productivity.

Upper crustal structure of the Hawaiian Swell from seafloor compliance measurements

NASA Astrophysics Data System (ADS)

Doran, A. K.; Laske, G.

2017-12-01

We present new constraints on elastic properties of the marine sediments and crust surrounding the Hawaiian Islands derived from seafloor compliance measurements. We analyze long-period seismic and pressure data collected during the Plume-Lithosphere Undersea Mantle Experiment [Laske et al, 2009], a deployment consisting of nearly 70 broadband ocean-bottom seismometers with an array aperture of over 1000 kilometers. Our results are supported by previous reflection & refraction studies and by direct sampling of the crust from regional drilling logs. We demonstrate the importance of simultaneously modeling density, compressional velocity, and shear velocity, the former two of which are often ignored during compliance investigations. We find variable sediment thickness and composition across the Hawaiian Swell, with the thickest sediments located within the Hawaiian Moat. Improved resolution of near-surface structure of the Hawaiian Swell is crucially important to improve tomographic images of the underlying lithosphere and asthenosphere and to address outstanding questions regarding the size, source, and location of the hypothesized mantle plume.

Evidence for the secondary sexual development of the anal fin in female kokanee salmon Oncorhynchus nerka.

PubMed

Thorn, M W; Morbey, Y E

2016-02-01

This study examines whether the anal fin undergoes secondary sexual development similar to other reproductive traits in salmonids. This hypothesis was tested by comparing the anal-fin size of female kokanee salmon Oncorhynchus nerka that were in the early and late stages of sexual development. Females in an advanced stage of maturation had significantly larger anal fins relative to females in an early state of maturation (+4-7%), indicating that the anal fin undergoes secondary sexual development. The magnitude of this secondary growth was comparable with snout length (+9-10%), which is known to undergo secondary sexual development in female salmonids. When morphological trait dimensions were compared between the sexes, the anal fin was the only morphological trait found to have a female-biased sexual size dimorphism. This is the first study to show that the anal fin of female salmonids undergoes secondary sexual development. © 2015 The Fisheries Society of the British Isles.

The effectiveness of sexual offender treatment for juveniles as measured by recidivism: a meta-analysis.

PubMed

Reitzel, Lorraine R; Carbonell, Joyce L

2006-10-01

Published and unpublished data from nine studies on juvenile sexual offender treatment effectiveness were summarized by meta-analysis (N=2986, 2604 known male). Recidivism rates for sexual, non-sexual violent, non-sexual non-violent crimes, and unspecified non-sexual were as follows: 12.53%, 24.73%, 28.51%, and 20.40%, respectively, based on an average 59-month follow-up period. Four included studies contained a control group (n=2288) and five studies included a comparison treatment group (n=698). An average weighted effect size of 0.43 (CI=0.33-0.55) was obtained, indicating a statistically significant effect of treatment on sexual recidivism. However, individual study characteristics (e.g., handling of dropouts and non-equivalent follow-up periods between treatment groups) suggest that results should be interpreted with caution. A comparison of odds ratios by quality of study design indicated that higher quality designs yielded better effect sizes, though the difference between groups was not significant.

Superficial dorsal vein injury/thrombosis presenting as false penile fracture requiring dorsal venous ligation.

PubMed

Rafiei, Arash; Hakky, Tariq S; Martinez, Daniel; Parker, Justin; Carrion, Rafael

2014-12-01

Conditions mimicking penile fracture are extremely rare and have been seldom described. To describe a patient with false penile fracture who presented with superficial dorsal vein injury/thrombosis managed with ligation. A 33-year-old male presented with penile swelling and ecchymosis after intercourse. A penile ultrasound demonstrated a thrombosed superficial dorsal vein but also questionable fracture of the tunica albuginea. As the thrombus was expanding, he was emergently taken to the operating room for exploration and required only dorsal venous ligation. Postoperatively, patient's Sexual Health Inventory for Men score was 23, and he had no issues with erections or sexual intercourse. Early exploration of patients with suspected penile fracture provides excellent results with maintenance of erectile function. Also, in the setting of dorsal vein thrombosis, ligation preserves the integrity of the penile tissues and avoids unnecessary complications from conservative management. Rafiei A, Hakky TS, Martinez D, Parker J, and Carrion R. Superficial dorsal vein injury/thrombosis presenting as false penile fracture requiring dorsal venous ligation.

Migrate small, sound big: functional constraints on body size promote tracheal elongation in cranes.

PubMed

Jones, M R; Witt, C C

2014-06-01

Organismal traits often represent the outcome of opposing selection pressures. Although social or sexual selection can cause the evolution of traits that constrain function or survival (e.g. ornamental feathers), it is unclear how the strength and direction of selection respond to ecological shifts that increase the severity of the constraint. For example, reduced body size might evolve by natural selection to enhance flight performance in migratory birds, but social or sexual selection favouring large body size may provide a countervailing force. Tracheal elongation is a potential outcome of these opposing pressures because it allows birds to convey an auditory signal of exaggerated body size. We predicted that the evolution of migration in cranes has coincided with a reduction in body size and a concomitant intensification of social or sexual selection for apparent large body size via tracheal elongation. We used a phylogenetic comparative approach to examine the relationships among migration distance, body mass and trachea length in cranes. As predicted, we found that migration distance correlated negatively with body size and positively with proportional trachea length. This result was consistent with our hypothesis that evolutionary reductions in body size led to intensified selection for trachea length. The most likely ultimate causes of intensified positive selection on trachea length are the direct benefits of conveying a large body size in intraspecific contests for mates and territories. We conclude that the strength of social or sexual selection on crane body size is linked to the degree of functional constraint. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Sexual size dimorphism, canine dimorphism, and male-male competition in primates: where do humans fit in?

PubMed

Plavcan, J Michael

2012-03-01

Sexual size dimorphism is generally associated with sexual selection via agonistic male competition in nonhuman primates. These primate models play an important role in understanding the origins and evolution of human behavior. Human size dimorphism is often hypothesized to be associated with high rates of male violence and polygyny. This raises the question of whether human dimorphism and patterns of male violence are inherited from a common ancestor with chimpanzees or are uniquely derived. Here I review patterns of, and causal models for, dimorphism in humans and other primates. While dimorphism in primates is associated with agonistic male mate competition, a variety of factors can affect male and female size, and thereby dimorphism. The causes of human sexual size dimorphism are uncertain, and could involve several non-mutually-exclusive mechanisms, such as mate competition, resource competition, intergroup violence, and female choice. A phylogenetic reconstruction of the evolution of dimorphism, including fossil hominins, indicates that the modern human condition is derived. This suggests that at least some behavioral similarities with Pan associated with dimorphism may have arisen independently, and not directly from a common ancestor.

BODY SIZE AND HAREM SIZE IN MALE RED-WINGED BLACKBIRDS: MANIPULATING SELECTION WITH SEX-SPECIFIC FEEDERS.

PubMed

Rohwer, Sievert; Langston, Nancy; Gori, Dave

1996-10-01

We experimentally manipulated the strength of selection in the field on red-winged blackbirds (Agelaius phoeniceus) to test hypotheses about contrasting selective forces that favor either large or small males in sexually size dimorphic birds. Selander (1972) argued that sexual selection favors larger males, while survival selection eventually stabilizes male size because larger males do not survive as well as smaller males during harsh winters. Searcy (1979a) proposed instead that sexual selection may be self limiting: male size might be stabilized not by overwinter mortality, but by breeding-season sexual selection that favors smaller males. Under conditions of energetic stress, smaller males should be able to display more and thus achieve higher reproductive success. Using feeders that provisioned males or females but not both, we produced conditions that mimicked the extremes of natural conditions. We found experimental support for the hypothesis that when food is abundant, sexual selection favors larger males. But even under conditions of severe energetic stress, smaller males did not gain larger harems, as the self-limiting hypothesis predicted. Larger males were more energetically stressed than smaller males, but in ways that affected their future reproductive output rather than their current reproductive performance. Stressed males that returned had smaller wings and tails than those that did not return; among returning stressed males, relative harem sizes were inversely related to wing and tail length. Thus, male body size may be stabilized not by survival costs during the non-breeding season, nor by energetic costs during the breeding season, but by costs of future reproduction that larger males pay for their increased breeding-season effort. © 1996 The Society for the Study of Evolution.

Variation in Craniomandibular Morphology and Sexual Dimorphism in Pantherines and the Sabercat Smilodon fatalis

PubMed Central

Christiansen, Per; Harris, John M.

2012-01-01

Sexual dimorphism is widespread among carnivorans, and has been an important evolutionary factor in social ecology. However, its presence in sabertoothed felids remains contentious. Here we present a comprehensive analysis of extant Panthera and the sabertoothed felid Smilodon fatalis. S. fatalis has been reported to show little or no sexual dimorphism but to have been intraspecifically variable in skull morphology. We found that large and small specimens of S. fatalis could be assigned to male and female sexes with similar degrees of confidence as Panthera based on craniomandibular shape. P. uncia is much less craniomandibularly variable and has low levels of sexual size-dimorphism. Shape variation in S. fatalis probably reflects sexual differences. Craniomandibular size-dimorphism is lower in S. fatalis than in Panthera except P. uncia. Sexual dimorphism in felids is related to more than overall size, and S. fatalis and the four large Panthera species show marked and similar craniomandibular and dental morphometric sexual dimorphism, whereas morphometric dimorphism in P. uncia is less. Many morphometric-sexually dimorphic characters in Panthera and Smilodon are related to bite strength and presumably to killing ecology. This suggests that morphometric sexual dimorphism is an evolutionary adaptation to intraspecific resource partitioning, since large males with thicker upper canines and stronger bite forces would be able to hunt larger prey than females, which is corroborated by feeding ecology in P. leo. Sexual dimorphism indicates that S. fatalis could have been social, but it is unlikely that it lived in fusion-fission units dominated by one or a few males, as in sub-Saharan populations of P. leo. Instead, S. fatalis could have been solitary and polygynous, as most extant felids, or it may have lived in unisexual groups, as is common in P. leo persica. PMID:23110232

Shared social and emotional activities within adolescent romantic and non-romantic sexual relationships.

PubMed

Williams, Lela Rankin; Russell, Stephen T

2013-05-01

Typically, "non-romantic" sexual relationships are assumed to be casual; however, the emotional and social distinctions between romantic and non-romantic contexts are not well understood, particularly in adolescence. Data from the National Longitudinal Study of Adolescent Health (Add Health) was used to compare shared emotional (e.g., telling partner that they love her/him) and social (e.g., going out in a group) activities within romantic and non-romantic sexual relationships. Adolescents who reported exclusively romantic sexual relationships (n = 1,891) shared more emotional, but not social, activities with their partners than adolescents who were in non-romantic sexual relationships (n = 315; small effect size, r = .07-.13), akin to adolescents who experienced both relationship types (n = 519; small-to-medium effect size, r = .18-.38). Girls shared more emotional and social activities with their partners than boys when in romantic relationships (small effect size, r = .06-.10); there were no significant gender differences within non-romantic sexual relationships. Findings suggest that gendered scripts remain for sexual relationships that are romantic but not for those that are non-romantic. Notably, for the majority of adolescents, non-romantic relationships still held many emotional and social dimensions typical of romantic relationships and differences between relationship types were small. Although non-romantic relationships were less intimate than romantic sexual relationships, there was remarkable heterogeneity within this relationship type. Caution is advised when working with adolescents engaged in "casual" sexual relationships. Understanding the complexity of adolescent sexual relationships is critical for the advancement of effective sex education programming.

Sexual dimorphism of head morphology in three-spined stickleback Gasterosteus aculeatus.

PubMed

Aguirre, W E; Akinpelu, O

2010-09-01

This study examined sexual dimorphism of head morphology in the ecologically diverse three-spined stickleback Gasterosteus aculeatus. Male G. aculeatus had longer heads than female G. aculeatus in all 10 anadromous, stream and lake populations examined, and head length growth rates were significantly higher in males in half of the populations sampled, indicating that differences in head size increased with body size in many populations. Despite consistently larger heads in males, there was significant variation in size-adjusted head length among populations, suggesting that the relationship between head length and body length was flexible. Inter-population differences in head length were correlated between sexes, thus population-level factors influenced head length in both sexes despite the sexual dimorphism present. Head shape variation between lake and anadromous populations was greater than that between sexes. The common divergence in head shape between sexes across populations was about twice as important as the sexual dimorphism unique to each population. Finally, much of the sexual dimorphism in head length was due to divergence in the anterior region of the head, where the primary trophic structures were found. It is unclear whether the sexual dimorphism was due to natural selection for niche divergence between sexes or sexual selection. This study improves knowledge of the magnitude, growth rate divergence, inter-population variation and location of sexual dimorphism in G. aculeatus head morphology. © 2010 The Authors. Journal compilation © 2010 The Fisheries Society of the British Isles.

Multifunctional medicated lyophilised wafer dressing for effective chronic wound healing.

PubMed

Pawar, Harshavardhan V; Boateng, Joshua S; Ayensu, Isaac; Tetteh, John

2014-06-01

Wafers combining weight ratios of Polyox with carrageenan (75/25) or sodium alginate (50/50) containing streptomycin and diclofenac were prepared to improve chronic wound healing. Gels were freeze-dried using a lyophilisation cycle incorporating an annealing step. Wafers were characterised for morphology, mechanical and in vitro functional (swelling, adhesion, drug release in the presence of simulated wound fluid) characteristics. Both blank (BLK) and drug-loaded (DL) wafers were soft, flexible, elegant in appearance and non-brittle in nature. Annealing helped to improve porous nature of wafers but was affected by the addition of drugs. Mechanical characterisation demonstrated that the wafers were strong enough to withstand normal stresses but also flexible to prevent damage to newly formed skin tissue. Differences in swelling, adhesion and drug release characteristics could be attributed to differences in pore size and sodium sulphate formed because of the salt forms of the two drugs. BLK wafers showed relatively higher swelling and adhesion than DL wafers with the latter showing controlled release of streptomycin and diclofenac. The optimised dressing has the potential to reduce bacterial infection and can also help to reduce swelling and pain associated with injury due to the anti-inflammatory action of diclofenac and help to achieve more rapid wound healing. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Encapsulation of the antioxidant ascorbyl palmitate in V-type granular cold-water swelling starch affects the properties of both.

PubMed

Dries, D M; Knaepen, L; Goderis, B; Delcour, J A

2017-06-01

This study reports on the functionality of V-type crystalline granular cold-water swelling starch (GCWSS) in complex with lipid (functionalized) molecules. Maize and potato GCWSS contain (empty) single helical amylose (AM) crystals which can serve as lipid complexing matrices. Different concentrations of ascorbyl palmitate (AscP) were inserted in the hydrophobic cavities of the GCWSS AM helices by a low temperature infusion method. Volumetric particle size distributions of the ensuing products in water were determined using laser light scattering. Upon contact with water, the parent maize GCWSS formed lumps more than did the parent potato GCWSS. It is hypothesized that variations in the spatial distribution of cold-water soluble V-type crystals are at the origin of this difference. In contrast, GCWSS-AscP inclusion complexes formed homogenous dispersions in water. Furthermore, the impact of inclusion complex formation on cold-water swelling properties was investigated. The close packing concentration increased and the swelling power and carbohydrate leaching decreased when the level of encapsulated AscP increased. Finally, in a Trolox equivalent antioxidant capacity test, encapsulated AscP still had up to 70% of the antioxidant capacity of free AscP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genipin-modified gelatin nanocarriers as swelling controlled drug delivery system for in vitro release of cytarabine.

PubMed

Khan, Huda; Shukla, R N; Bajpai, A K

2016-04-01

The aim of the present investigation was to design biocompatible gelatin nanoparticles, capable of releasing the cytarabine drug in a controllable way by regulating the extent of swelling of nanoparticles. In order to achieve the proposed objectives, gelatin (Type A, derived from acid cured tissue) was modified by crosslinking with genipin and nanoparticles of crosslinked gelatin were prepared using single water in oil (W/O) emulsion technique. The nanoparticles were characterized by techniques like FTIR, SEM, TEM, particles size analysis, and surface potential measurements. The nanoparticle chemical architecture was found to influence drug-releasing capacity. The influence of experimental conditions such as pH and simulated physiological fluids as the release medium was also investigated on the release profiles of cytarabine. It is possible to fabricate high-performance materials, by designing of controlled size gelatin nanoparticles with good biocompatible properties along with desired drug release profiles. Copyright © 2015 Elsevier B.V. All rights reserved.

Soft-tissue reactions following irradiation of primary brain and pituitary tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baglan, R.J.; Marks, J.E.

1981-04-01

One hundred and ninety-nine patients who received radiation therapy for a primary brain or pituitary tumor were studied for radiation-induced soft-tissue reactions of the cranium, scalp, ears and jaw. The frequency of these reactions was studied as a function of: the radiation dose 5 mm below the skin surface, dose distribution, field size and fraction size. Forty percent of patients had complete and permanent epilation, while 21% had some other soft-tissue complication, including: scalp swelling-6%, external otitis-6%, otitis media-5%, ear swelling-4%, etc. The frequency of soft-tissue reactions correlates directly with the radiation dose at 5 mm below the skin surface.more » Patients treated with small portals (<70 cm/sup 2/) had few soft-tissue reactions. The dose to superficial tissues, and hence the frequency of soft-tissue reactions can be reduced by: (1) using high-energy megavoltage beams; (2) using equal loading of beams; and (3) possibly avoiding the use of electron beams.« less

Mesoscale model for fission-induced recrystallization in U-7Mo alloy

DOE PAGES

Liang, Linyun; Mei, Zhi -Gang; Kim, Yeon Soo; ...

2016-08-09

A mesoscale model is developed by integrating the rate theory and phase-field models and is used to study the fission-induced recrystallization in U-7Mo alloy. The rate theory model is used to predict the dislocation density and the recrystallization nuclei density due to irradiation. The predicted fission rate and temperature dependences of the dislocation density are in good agreement with experimental measurements. This information is used as input for the multiphase phase-field model to investigate the fission-induced recrystallization kinetics. The simulated recrystallization volume fraction and bubble induced swelling agree well with experimental data. The effects of the fission rate, initial grainmore » size, and grain morphology on the recrystallization kinetics are discussed based on an analysis of recrystallization growth rate using the modified Avrami equation. Here, we conclude that the initial microstructure of the U-Mo fuels, especially the grain size, can be used to effectively control the rate of fission-induced recrystallization and therefore swelling.« less

Grain growth in U–7Mo alloy: A combined first-principles and phase field study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mei, Zhi-Gang; Liang, Linyun; Kim, Yeon Soo

2016-05-01

Grain size is an important factor in controlling the swelling behavior in irradiated U-Mo dispersion fuels. Increasing the grain size in UeMo fuel particles by heat treatment is believed to delay the fuel swelling at high fission density. In this work, a multiscale simulation approach combining first-principles calculation and phase field modeling is used to investigate the grain growth behavior in U-7Mo alloy. The density functional theory based first-principles calculations were used to predict the material properties of U-7Mo alloy. The obtained grain boundary energies were then adopted as an input parameter for mesoscale phase field simulations. The effects ofmore » annealing temperature, annealing time and initial grain structures of fuel particles on the grain growth in U-7Mo alloy were examined. The predicted grain growth rate compares well with the empirical correlation derived from experiments. (C) 2016 Elsevier B.V. All rights reserved.« less

Low-load resistance training with low relative pressure produces muscular changes similar to high-load resistance training.

PubMed

Kim, Daeyeol; Loenneke, Jeremy P; Ye, Xin; Bemben, Debra A; Beck, Travis W; Larson, Rebecca D; Bemben, Michael G

2017-12-01

This study compares the acute and chronic response of high-load resistance training (HL) to low-load resistance training with low blood flow restriction (LL-BFR) pressure. Participants completed elbow flexion with either HL or LL-BFR or nonexercise. In the chronic study, participants in the HL and LL-BFR groups were trained for 8 weeks to determine differences in muscle size and strength. The acute study examined the changes in pretesting/posttesting (Pre/Post) torque, muscle swelling, and blood lactate. In the chronic study, similar changes in muscle size and strength were observed for both HL and LL-BFR. In the acute study, Pre/Post changes in the torque, muscle swelling, and blood lactate were similar between HL and LL-BFR. Our findings indicate that pressure as low as 50% arterial occlusion can produce similar changes in muscle mass and strength compared with traditional HL. Muscle Nerve 56: E126-E133, 2017. © 2017 Wiley Periodicals, Inc.

A study of factors affecting properties of AM/AMPS/NVP terpolymeric microspheres prepared by inverse suspension polymerization

NASA Astrophysics Data System (ADS)

Jiang, J. F.; Zhao, Q.; Lin, M. Q.; Wang, Y. F.; Dang, S. M.; Sun, F. F.

2015-12-01

Terpolymeric microspheres were synthesized by the inverse suspension polymerization of functional monomers including AMPS, NVP, and AM. The morphology and size of the obtained microspheres were measured by scanning electron microscopy (SEM) and optical microscopy. Furthermore, the swelling performances of the obtained microspheres were measured with alaser particle analyzer (LPA), and the thermal stability of the microspheres obtained was measured by differential thermal analysis (DSC-TG) and high temperature experiments involving microsphere/water dispersion. The results revealed that the extreme value of the microsphere size distribution decreased from 280 μm to 20 μm as the stirring rate increased from 175 rpm to 500 rpm. At temperatures below 25°C, the maximum achieved swelling ratio of the microspheres was 21, and the thermal stability of the terpolymer microspheres was significantly higher than that of the dipolymer microspheres. The terpolymer/water dispersions were kept at 120°C for 19d before any damage was observed.

Computer simulations of melts of randomly branching polymers

NASA Astrophysics Data System (ADS)

Rosa, Angelo; Everaers, Ralf

2016-10-01

Randomly branching polymers with annealed connectivity are model systems for ring polymers and chromosomes. In this context, the branched structure represents transient folding induced by topological constraints. Here we present computer simulations of melts of annealed randomly branching polymers of 3 ≤ N ≤ 1800 segments in d = 2 and d = 3 dimensions. In all cases, we perform a detailed analysis of the observed tree connectivities and spatial conformations. Our results are in excellent agreement with an asymptotic scaling of the average tree size of R ˜ N1/d, suggesting that the trees behave as compact, territorial fractals. The observed swelling relative to the size of ideal trees, R ˜ N1/4, demonstrates that excluded volume interactions are only partially screened in melts of annealed trees. Overall, our results are in good qualitative agreement with the predictions of Flory theory. In particular, we find that the trees swell by the combination of modified branching and path stretching. However, the former effect is subdominant and difficult to detect in d = 3 dimensions.

Non-random pairing in American kestrels: mate choice versus intra-sexual competition

USGS Publications Warehouse

Bortolotti, Gary R.; Iko, William M.

1992-01-01

Natural selection may influence the arrangement of individuals into mated pairs through either inter-sexual (mate choice) or intra-sexual selection (competition). A study of the American kestrel, Falco sparverius, in northern Saskatchewan distinguished between these two processes using size as a measure of the bird's competitive ability, and condition (mass scaled to body size) as an index of quality. Both sexes arrive on the study area after spring migration in equal numbers and males establish territories. Males and females that moved among territories at the time of pair formation were not different in size or condition from those that did not move, suggesting that birds were not being displaced by superior competitors, and that females moved to encounter potential mates. Within mated pairs, there was no relationship between a bird's size and the condition of its mate for either sex as would be predicted if intra-sexual competitition explained mating patterns. Instead, there was positive assortative mating by condition, suggesting that both sexes used quality as the criterion in choosing mates. There was no correlation between the sizes of males and females in mated paird. Because there were no differences in size or condition of breeding and non-breeding males, factors other than physical attributes, such as prior experience with the area, may determine a male's success in obtaining a territory. Because females that did not obtain mates were in poorer condition than those that did, males may have rejected poor quality females. The results suggest that intra-sexual competition was not important for pair formation, and that kestrels chose mates on the basis of quality.

Peripheral Female Genital Arousal as Assessed by Thermography Following Topical Genital Application of Alprostadil vs Placebo Arousal Gel: A Proof-of-Principle Study Without Visual Sexual Stimulation.

PubMed

Goldstein, Sue W; Gonzalez, Joshua R; Gagnon, Catherine; Goldstein, Irwin

2016-09-01

Female sexual arousal disorder is a pathophysiologic state characterized clinically by persistent or recurrent inability to attain or maintain an adequate lubrication-swelling response of sexual excitement until completion of sexual activity. Prior clinical experience with alprostadil products for men with erectile dysfunction supports its use in women with female sexual arousal disorder. To compare the effect of topical alprostadil with over-the-counter (OTC) lubricant on female genital arousal in the absence of visual sexual stimuli. Healthy premenopausal women without sexual dysfunction were recruited from the community to participate in the study. Of 17 women who consented, 10 were enrolled and completed the trial. The mean age of subjects was 32 years (range = 27-43). Study drug or placebo was applied topically to the genitals. Continuous temperature monitoring was performed. Participants completed questionnaires assessing genital sensation, effect, intensity, and duration. Change in temperature from baseline in vestibule, clitoris and vulva. In all 10 subjects, topical alprostadil induced a statistically significant increase in temperature of the vestibule, clitoris, and vulva compared with the OTC lubricant. The most rapid difference in genital temperature between placebo and alprostadil was seen on the vulva, which demonstrated a significant difference at approximately 9 minutes. There was a significant difference in temperature seen for the vestibule and clitoris at 11 and 19 minutes, respectively. Sixty percent of women reported being aware or conscious of genital sensations with topical alprostadil, but not with OTC lubricant. Discordance was noted in 30% of subjects who reported being aware or conscious of genital sensations with the two treatments and 10% who reported not being aware or conscious of genital sensations with either treatment. Topical alprostadil administered to healthy premenopausal women induced statistically significant, sustained increases in genital temperatures of the vestibule, clitoris, and vulva within 20 minutes compared with OTC lubricant. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Sexually dichromatic coloration reflects size and immunocompetence in female Spanish terrapins, Mauremys leprosa

NASA Astrophysics Data System (ADS)

Ibáñez, Alejandro; Marzal, Alfonso; López, Pilar; Martín, José

2013-12-01

Many studies have shown the importance of colorful ornamentation in mate choosiness or intrasexual conflict. However, research on color ornaments has focused mainly on birds, lizards or fish, but remains practically unknown in other animal groups such as turtles. In addition, female ornaments and their relation with sexual selection also remain almost unknown. Here, we measured the coloration of the shell and the limb stripes of male and female Spanish terrapins Mauremys leprosa and explored the existence of sexual dichromatism and the relation of color characteristics with body size and health state estimated from the immune response to the injection of an antigen (phytohaemagglutinin test). Our results showed that shell coloration, which could be constrained by natural selection to be cryptic, changed with body size, but did not differ between sexes. In contrast, females had brighter and less ultraviolet-saturated and more orange-saturated limb stripes than males. In females, interindividual variation in limb stripe coloration was related with body size and immune response suggesting that this coloration may inform honestly about multiple traits that could be important in sexual selection. In contrast, coloration of limb stripes of males was duller than in females, and was not related with any trait suggesting that coloration is not important in sexual selection for males.

Drought survival and reproduction impose contrasting selection pressures on maximum body size and sexual size dimorphism in a snake, Seminatrix pygaea.

PubMed

Winne, Christopher T; Willson, John D; Whitfield Gibbons, J

2010-04-01

The causes and consequences of body size and sexual size dimorphism (SSD) have been central questions in evolutionary ecology. Two, often opposing selective forces are suspected to act on body size in animals: survival selection and reproductive (fecundity and sexual) selection. We have recently identified a system where a small aquatic snake species (Seminatrix pygaea) is capable of surviving severe droughts by aestivating within dried, isolated wetlands. We tested the hypothesis that the lack of aquatic prey during severe droughts would impose significant survivorship pressures on S. pygaea, and that the largest individuals, particularly females, would be most adversely affected by resource limitation. Our findings suggest that both sexes experience selection against large body size during severe drought when prey resources are limited, as nearly all S. pygaea are absent from the largest size classes and maximum body size and SSD are dramatically reduced following drought. Conversely, strong positive correlations between maternal body size and reproductive success in S. pygaea suggest that females experience fecundity selection for large size during non-drought years. Collectively, our study emphasizes the dynamic interplay between selection pressures that act on body size and supports theoretical predictions about the relationship between body size and survivorship in ectotherms under conditions of resource limitation.

Specialization in and within sexual offending in England and Wales.

PubMed

Howard, Philip D; Barnett, Georgia D; Mann, Ruth E

2014-06-01

Existing evidence suggests that offenders tend not to specialize in sexual offending in general but that there is some specialization in particular types of sexual offending. This study examined the sexual histories and reoffending of a large, national data set of offenders convicted of a sexual offense and managed in England and Wales by the National Offender Management Service (N = 14,804). The study found that specialization in sexual offending compared to nonsexual offending was most evident for offenders with convictions for accessing indecent images. We also found considerable evidence of specialization within sexual offending, most notably for noncontact offenders, especially again indecent images offenders. Crossover between sexual offense types was very rare for those with contact adult offenses and for noncontact offenders although those with child contact offenses sometimes crossed over to indecent images reoffending. If specialization within sexual offending exists, the use of single risk assessment instruments to predict all types of sexual recidivism may be less effective than previously assumed. A comparison of different prediction models indicated that some items presently used in one-size-fits-all risk tools to predict any sexual reoffending only effectively predict certain subtypes of sexual offending. Statistically there appear to be some potential benefits to creating specialist risk predictors for different subtypes of offending, but further work is needed to justify the implementation demands that would be caused by abandoning one-size-fits-all tools.

Body Size Adaptations to Altitudinal Climatic Variation in Neotropical Grasshoppers of the Genus Sphenarium (Orthoptera: Pyrgomorphidae)

PubMed Central

2015-01-01

Altitudinal clines in body size can result from the effects of natural and sexual selection on growth rates and developing times in seasonal environments. Short growing and reproductive seasons constrain the body size that adults can attain and their reproductive success. Little is known about the effects of altitudinal climatic variation on the diversification of Neotropical insects. In central Mexico, in addition to altitude, highly heterogeneous topography generates diverse climates that can occur even at the same latitude. Altitudinal variation and heterogeneous topography open an opportunity to test the relative impact of climatic variation on body size adaptations. In this study, we investigated the relationship between altitudinal climatic variation and body size, and the divergence rates of sexual size dimorphism (SSD) in Neotropical grasshoppers of the genus Sphenarium using a phylogenetic comparative approach. In order to distinguish the relative impact of natural and sexual selection on the diversification of the group, we also tracked the altitudinal distribution of the species and trends of both body size and SSD on the phylogeny of Sphenarium. The correlative evidence suggests no relationship between altitude and body size. However, larger species were associated with places having a warmer winter season in which the temporal window for development and reproduction can be longer. Nonetheless, the largest species were also associated with highly seasonal environments. Moreover, large body size and high levels of SSD have evolved independently several times throughout the history of the group and male body size has experienced a greater evolutionary divergence than females. These lines of evidence suggest that natural selection, associated with seasonality and sexual selection, on maturation time and body size could have enhanced the diversification of this insect group. PMID:26684616

Ornament size and colour as alternative strategies for effective communication in gliding lizards.

PubMed

Klomp, D A; Ord, T J; Das, I; Diesmos, A; Ahmad, N; Stuart-Fox, D

2016-09-01

Sexual ornamentation needs to be conspicuous to be effective in attracting potential mates and defending territories and indeed, a multitude of ways exists to achieve this. Two principal mechanisms for increasing conspicuousness are to increase the ornament's colour or brightness contrast against the background and to increase the size of the ornament. We assessed the relationship between the colour and size of the dewlap, a large extendible throat-fan, across a range of species of gliding lizards (Agamidae; genus Draco) from Malaysia and the Philippines. We found a negative relationship across species between colour contrast against the background and dewlap size in males, but not in females, suggesting that males of different species use increasing colour contrast and dewlap size as alternative strategies for effective communication. Male dewlap size also increases with increasing sexual size dimorphism, and dewlap colour and brightness contrast increase with increasing sexual dichromatism in colour and brightness, respectively, suggesting that sexual selection may act on both dewlap size and colour. We further found evidence that relative predation intensity, as measured from predator attacks on models placed in the field, may play a role in the choice of strategy (high chromatic contrast or large dewlap area) a species employs. More broadly, these results highlight that each component in a signal (such as colour or size) may be influenced by different selection pressures and that by assessing components individually, we can gain a greater understanding of the evolution of signal diversity. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Importance of sexuality in colorectal cancer: predictors, changes, and response to an intimacy enhancement intervention.

PubMed

Reese, Jennifer Barsky; Haythornthwaite, Jennifer A

2016-10-01

The primary objectives were (1) to examine the importance of sexuality within the self-view and cross-sectional correlates for 120 colorectal cancer patients and (2) to determine whether the importance of sexuality changed for 46 colorectal cancer patients and partners participating in an intimacy enhancement intervention. Two newly developed items assessed importance of sexuality within the self-view (1) currently and (2) before cancer; a calculated change score assessed perceived change. In the cross-sectional sample, associations between importance of sexuality and demographic and medical factors and sexual function status were examined. Intervention participants' importance ratings before and after participation were used to calculate effect sizes. For patients, importance of sexuality before cancer was greater (M = 65.7) than current importance (M = 56.8, p = .001). Greater current importance of sexuality was associated with partnered status, non-metastatic disease, and not being in treatment. Scoring in the sexually functional range was associated with greater current importance of sexuality for men and a smaller perceived change in importance for both men and women (p values <.05). Sexual function status also significantly predicted current importance independent of covariates. Small to medium effect sizes for intervention patients (.37) and partners (.60) were found for increases in importance of sexuality. Items showed evidence of test-retest reliability and construct validity. Coping with sexual concerns is important to those affected by colorectal cancer. Findings suggest that the importance of sexuality can decrease through colorectal cancer and associated sexual problems and can increase through participating in an intimacy-focused intervention.

Getting to the Bottom of Face Processing. Species-Specific Inversion Effects for Faces and Behinds in Humans and Chimpanzees (Pan Troglodytes).

PubMed

Kret, Mariska E; Tomonaga, Masaki

2016-01-01

For social species such as primates, the recognition of conspecifics is crucial for their survival. As demonstrated by the 'face inversion effect', humans are experts in recognizing faces and unlike objects, recognize their identity by processing it configurally. The human face, with its distinct features such as eye-whites, eyebrows, red lips and cheeks signals emotions, intentions, health and sexual attraction and, as we will show here, shares important features with the primate behind. Chimpanzee females show a swelling and reddening of the anogenital region around the time of ovulation. This provides an important socio-sexual signal for group members, who can identify individuals by their behinds. We hypothesized that chimpanzees process behinds configurally in a way humans process faces. In four different delayed matching-to-sample tasks with upright and inverted body parts, we show that humans demonstrate a face, but not a behind inversion effect and that chimpanzees show a behind, but no clear face inversion effect. The findings suggest an evolutionary shift in socio-sexual signalling function from behinds to faces, two hairless, symmetrical and attractive body parts, which might have attuned the human brain to process faces, and the human face to become more behind-like.

The tale of the shrinking weapon: seasonal changes in nutrition affect weapon size and sexual dimorphism, but not contemporary evolution.

PubMed

Miller, C W; McDonald, G C; Moore, A J

2016-11-01

Sexually selected traits are often highly variable in size within populations due to their close link with the physical condition of individuals. Nutrition has a large impact on physical condition, and thus, any seasonal changes in nutritional quality are predicted to alter the average size of sexually selected traits as well as the degree of sexual dimorphism in populations. However, although traits affected by mate choice are well studied, we have a surprising lack of knowledge of how natural variation in nutrition affects the expression of sexually selected weapons and sexual dimorphism. Further, few studies explicitly test for differences in the heritability and mean-scaled evolvability of sexually selected traits across conditions. We studied Narnia femorata (Hemiptera: Coreidae), an insect where males use their hind legs as weapons and the femurs are enlarged, to understand the extent to which weapon expression, sexual dimorphism and evolvability change across the actual range of nutrition available in the wild. We found that insects raised on a poor diet (cactus without fruit) are nearly monomorphic, whereas those raised on a high-quality diet (cactus with ripe fruit) are distinctly sexually dimorphic via the expression of large hind leg weapons in males. Contrary to our expectations, we found little evidence of a potential for evolutionary change for any trait measured. Thus, although we show weapons are highly condition dependent, and changes in weapon expression and dimorphism could alter evolutionary dynamics, our populations are unlikely to experience further evolutionary changes under current conditions. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird.

PubMed

Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S; Redpath, S M

2014-05-01

In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context. Copyright © 2014 Elsevier Inc. All rights reserved.

Vibrators and other sex toys are commonly recommended to patients, but does size matter? Dimensions of commonly sold products.

PubMed

Herbenick, Debby; Barnhart, Kathryn J; Beavers, Karly; Benge, Stephanie

2015-03-01

Vibrators and dildos are commonly used by women and men in the United States, and are increasingly recommended by clinicians. In addition, sex toys and various household objects are sometimes used for sexual stimulation in ways that pose health risks to their users. Data about the dimensions of such products may inform clinicians' recommendations. The purpose of the present study was to assess the sizes (length and circumference) of vibrators and dildos marketed for vaginal or anal insertion on websites that sell sexual enhancement products. Eight websites that sell sexual enhancement products were identified for inclusion in the study. The dimensions of vaginal vibrators and dildos listed for sale on each website were noted, and descriptive data were calculated for each website. Product length and circumference (mean, median, and range). Popular sex toy distributers offer a variety of product sizes. The length of many vibrators and dildos was sized between 4 and 6 in, and circumference was between 4 and 5 in. However, some companies featured products of a considerably larger size than others. Length and circumference of vibrators and dildos varied, but on average approximated mean penile dimensions. Clinicians' recommendations for use of vaginal or anal products can be enhanced by familiarity and offering additional information about product sizes and retailers. © 2015 International Society for Sexual Medicine.

Critical weight mediates sex-specific body size plasticity and sexual dimorphism in the yellow dung fly Scathophaga stercoraria (Diptera: Scathophagidae).

PubMed

Rohner, Patrick T; Blanckenhorn, Wolf U; Schäfer, Martin A

2017-05-01

Ultimate factors driving insect body size are rather well understood, while-apart from a few model species-the underlying physiological and developmental mechanisms received less attention. We investigate the physiological basis of adaptive size variation in the yellow dung fly Scathophaga stercoraria, which shows pronounced male-biased sexual size dimorphism and strong body size plasticity. We estimate variation of a major physiological threshold, the critical weight, which is the mass at which a larva initiates pupariation. Critical weight was associated with sexual size dimorphism and sex-specific plasticity, and is thus a likely target of selection on adult size. Detailed larval growth trajectories derived from individuals raised at two food and temperature treatments further reveal that sex-specific size plasticity is mediated by faster initial growth of males that later becomes reduced by higher male weight loss during the wandering stage. We further demonstrate that integral growth rates, which are typically calculated as simple ratios of egg-to-adult development time and adult weight, do not necessarily well reflect variation in instantaneous growth rates. We illustrate the importance of detailed assessments of ontogenetic growth trajectories for the understanding of adaptive size variation and discuss the mechanistic basis of size determination in shaping sex-specific phenotypic plasticity. © 2017 Wiley Periodicals, Inc.

Coevolution of female ovulatory signals and male-male competition in primates.

PubMed

Nakahashi, Wataru

2016-03-07

Visual signals of ovulation vary among primate species. Although slight ovulatory signals are considered primate ancestral traits of which some species still exhibit, some show prominent swelling of their perineal skin (exaggerated sexual swellings) and others do not exhibit any signals of ovulation (concealed ovulation). These signals strongly affect male mating behaviors. I develop an evolutionary model of female ovulatory signals and male-male competition. I assume that each male allocates his effort between attraction of females and male-male competition for dominance. Each female gains a benefit if she is fertile and free from the alpha male who always guards one of the most fertile females in the group, but suffers a cost if she expresses a different ovulatory signal from an ancestral trait. I show that various types of ovulatory signals may evolve and can be multistable. Male-male competition becomes intense when the signal honestly indicates ovulation. Ovulatory signals may evolve to be less exaggerated in unimale groups than in multimale groups and monogamy is more likely to evolve when ovulation is concealed. These results may partly explain why various types of primate ovulatory signals evolved and how they have affected primate societies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Size variation in Middle Pleistocene humans.

PubMed

Arsuaga, J L; Carretero, J M; Lorenzo, C; Gracia, A; Martínez, I; Bermúdez de Castro, J M; Carbonell, E

1997-08-22

It has been suggested that European Middle Pleistocene humans, Neandertals, and prehistoric modern humans had a greater sexual dimorphism than modern humans. Analysis of body size variation and cranial capacity variation in the large sample from the Sima de los Huesos site in Spain showed instead that the sexual dimorphism is comparable in Middle Pleistocene and modern populations.

Casual sex and concurrent sexual partnerships among young people from an Yi community with a high prevalence of HIV in China

PubMed Central

Yang, Yi; Luan, Rong-Sheng; Liu, Peng; Wu, Chun-Lin; Zhou, Ying; Chen, Wen

2012-01-01

Liangshan Prefecture in Sichuan province, China, has a high prevalence of HIV infection, which is reflective of a change in the mode of transmission from injection drug use (IDU) to heterosexual intercourse. However, few studies focus on HIV-related heterosexual risk behaviours among the majority Yi population. The objectives of this study were to explore the characteristics of an egocentric sexual network and estimate the prevalence of casual sexual behaviour. Yi villagers (n=108), aged 15–35 years, who reported having had sex within the previous year were interviewed as to their sexual behaviours and networks. In-depth interviews and focus group discussions provided supplementary information on sexual norms. Logistic regression analysis was used to calculate unadjusted odds ratios (ORs) and 95% confidence intervals (CIs). Most of the respondents reported having had casual sex at some time in their life, and 66.7% reported multiple sexual partnerships. Only 21.3% reported ever having used a condom. During the study year, a total of 137 partners were involved in 153 sexual partnerships. Among the reported sexual partnerships, 67.3% originated from a casual sexual relationship. For network members in components of size ≥3, 56.9% were involved in concurrent sexual partnerships. Having never been married (OR: 2.11; 95% CI: 1.03–4.33) and younger age (OR: 0.89; 95% CI: 0.83–0.95) were both associated with being in a component of size ≥3. Size (OR: 2.99; 95% CI: 1.17–7.66), pair (OR: 0.54; 95% CI: 0.39–0.74), the number of weak components of the egocentric sexual network (OR: 30.04; 95% CI: 6.47–139.46) and gender (OR: 0.19; 95% CI: 0.06–0.67) were all associated with being in concurrent sexual partnerships. HIV-related interventions for the Yi ethnic minority in Sichuan province must therefore address concurrent sexual partnerships and promote condom use. PMID:22683999

Sexual Minority Stress and Same-Sex Relationship Well-Being: A Meta-Analysis of Research Prior to the U.S. Nationwide Legalization of Same-Sex Marriage.

PubMed

Cao, Hongjian; Zhou, Nan; Fine, Mark; Liang, Yue; Li, Jiayao; Mills-Koonce, W Roger

2017-10-01

Meta-analytic methods were used to analyze 179 effect sizes retrieved from 32 research reports on the implications that sexual minority stress may have for same-sex relationship well-being. Sexual minority stress (aggregated across different types of stress) was moderately and negatively associated with same-sex relationship well-being (aggregated across different dimensions of relationship well-being). Internalized homophobia was significantly and negatively associated with same-sex relationship well-being, whereas heterosexist discrimination and sexual orientation visibility management were not. Moreover, the effect size for internalized homophobia was significantly larger than those for heterosexist discrimination and sexual orientation visibility management. Sexual minority stress was significantly and negatively associated with same-sex relationship quality but not associated with closeness or stability. Sexual minority stress was significantly and negatively associated with relationship well-being among same-sex female couples but not among same-sex male couples. The current status of research approaches in this field was also summarized and discussed.

The role of sexual selection and conflict in mediating among-population variation in mating strategies and sexually dimorphic traits in Sepsis punctum.

PubMed

Dmitriew, Caitlin; Blanckenhorn, Wolf U

2012-01-01

The black scavenger fly Sepsis punctum exhibits striking among-population variation in the direction and magnitude of sexual size dimorphism, modification to the male forelimb and pre-copulatory behaviour. In some populations, male-biased sexual size dimorphism is observed; in other, less dimorphic, populations males court prior to mating. Such variation in reproductive traits is of interest to evolutionary biologists because it has the potential to limit gene flow among populations, contributing to speciation. Here, we investigate whether large male body size and modified forefemur are associated with higher male mating success within populations, whether these traits are associated with higher mating success among populations, and if these traits carry viability costs that could constrain their response to sexual selection. Flies from five distinct populations were reared at high or low food, generating high and low quality males. The expression of body size, forelimb morphology and courtship rate were each greater at high food, but high food males experienced higher mating success or reduced latency to first copulation in only one of the populations. Among populations, overall mating success increased with the degree of male-bias in overall body size and forelimb modification, suggesting that these traits have evolved as a means of increasing male mating rate. The increased mating success observed in large-male populations raises the question of why variation in magnitude of dimorphism persists among populations. One reason may be that costs of producing a large size constrain the evolution of ever-larger males. We found no evidence that juvenile mortality under food stress was greater for large-male populations, but development time was considerably longer and may represent an important constraint in an ephemeral and competitive growth environment.

Low level of polyandry constrains phenotypic plasticity of male body size in mites.

PubMed

Schausberger, Peter; Walzer, Andreas; Murata, Yasumasa; Osakabe, Masahiro

2017-01-01

Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female) is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis). We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i) the effects of male body size on spermatophore transfer in singly mating females and (ii) the effects of mate sequence (switching the order of standard-sized and small males) on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized males was independent of the mating sequence. Based on our results and pertinent previous studies, which showed that females of P. persimilis, but not N. californicus, prefer mating with standard-sized over small males and allow them fertilizing more eggs, the lack of interspecific difference in female body size plasticity, and the absence of any clue pointing at a role of natural selection, we suggest that the interspecific difference in male body size plasticity is sexually selected. Our study provides an indication of sexual selection constraining plasticity of male phenotypes, suggesting that the level of polyandry may be an important co-determinant of the level of phenotypic plasticity of male body size.

Low level of polyandry constrains phenotypic plasticity of male body size in mites

PubMed Central

Walzer, Andreas; Murata, Yasumasa; Osakabe, Masahiro

2017-01-01

Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female) is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis). We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i) the effects of male body size on spermatophore transfer in singly mating females and (ii) the effects of mate sequence (switching the order of standard-sized and small males) on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized males was independent of the mating sequence. Based on our results and pertinent previous studies, which showed that females of P. persimilis, but not N. californicus, prefer mating with standard-sized over small males and allow them fertilizing more eggs, the lack of interspecific difference in female body size plasticity, and the absence of any clue pointing at a role of natural selection, we suggest that the interspecific difference in male body size plasticity is sexually selected. Our study provides an indication of sexual selection constraining plasticity of male phenotypes, suggesting that the level of polyandry may be an important co-determinant of the level of phenotypic plasticity of male body size. PMID:29190832

An Investigation into the Relationship between Human Cranial and Pelvic Sexual Dimorphism.

PubMed

Best, Kaleigh C; Garvin, Heather M; Cabo, Luis L

2017-10-16

When faced with commingled remains, it might be assumed that a more "masculine" pelvis is associated with a more "masculine" cranium, but this relationship has not been specifically tested. This study uses geometric morphometric analyses of pelvic and cranial landmarks to assess whether there is an intra-individual relationship between the degrees of sexual expression in these two skeletal regions. Principal component and discriminant function scores were used to assess sexual dimorphism in 113 U.S. Black individuals. Correlation values and partial least squares regression (PLS) were used to evaluate intra-individual relationships. Results indicate that the os coxae is more sexually dimorphic than the cranium, with element shape being more sexually dimorphic than size. PLS and correlation results suggest no significant intra-individual relationship between pelvic and cranial sexual size or shape expression. Thus, in commingled situations, associations between these skeletal elements cannot be inferred based on degree of "masculinity." © 2017 American Academy of Forensic Sciences.

Sexual display and mate choice in an energetically costly environment.

PubMed

Head, Megan L; Wong, Bob B M; Brooks, Robert

2010-12-09

Sexual displays and mate choice often take place under the same set of environmental conditions and, as a consequence, may be exposed to the same set of environmental constraints. Surprisingly, however, very few studies consider the effects of environmental costs on sexual displays and mate choice simultaneously. We conducted an experiment, manipulating water flow in large flume tanks, to examine how an energetically costly environment might affect the sexual display and mate choice behavior of male and female guppies, Poecilia reticulata. We found that male guppies performed fewer sexual displays and became less choosy, with respect to female size, in the presence of a water current compared to those tested in still water. In contrast to males, female responsive to male displays did not differ between the water current treatments and females exhibited no mate preferences with respect to male size or coloration in either treatment. The results of our study underscore the importance of considering the simultaneous effects of environmental costs on the sexual behaviors of both sexes.

The nature of allometry in an exaggerated trait: The postocular flange in Platyneuromus Weele (Insecta: Megaloptera).

PubMed

Ramírez-Ponce, Andrés; Garfias-Lozano, Gabriela; Contreras-Ramos, Atilano

2017-01-01

The origin and function of exaggerated traits exhibited by a great number of species with sexual dimorphism remain largely unexplored. The usual model considered as the evolutionary mechanism for the development of these structures is sexual selection. The nature of growth of the postocular flange (POF) in three species of the dobsonfly genus Platyneuromus (Megaloptera, Corydalidae, Corydalinae) is analyzed to explore sexual size dimorphism and allometric scaling. Results involve positive allometry of POF in males of two species, and negative allometry in males of one species, in general with a female-biased sexual dimorphism. We suggest an ancestral condition of dual incipient ornamentation in Platyneuromus, with a subsequent departure of size and shape of POF in males, triggered by sexual selection. Different sexual selection intensities may explain the parallel or divergent growth of POF within the scheme of dual ornamentation. Empirical behavioral data as well as a phylogenetic framework are necessary to clarify possible causes of phenotypic development, time of origin, and evolution of the POF.

Sexual selection and allometry: a critical reappraisal of the evidence and ideas.

PubMed

Bonduriansky, Russell

2007-04-01

One of the most pervasive ideas in the sexual selection literature is the belief that sexually selected traits almost universally exhibit positive static allometries (i.e., within a sample of conspecific adults, larger individuals have disproportionally larger traits). In this review, I show that this idea is contradicted by empirical evidence and theory. Although positive allometry is a typical attribute of some sexual traits in certain groups, the preponderance of positively allometric sexual traits in the empirical literature apparently results from a sampling bias reflecting a fascination with unusually exaggerated (bizarre) traits. I review empirical examples from a broad range of taxa illustrating the diversity of allometric patterns exhibited by signal, weapon, clasping and genital traits, as well as nonsexual traits. This evidence suggests that positive allometry may be the exception rather than the rule in sexual traits, that directional sexual selection does not necessarily lead to the evolution of positive allometry and, conversely, that positive allometry is not necessarily a consequence of sexual selection, and that many sexual traits exhibit sex differences in allometric intercept rather than slope. Such diversity in the allometries of secondary sexual traits is to be expected, given that optimal allometry should reflect resource allocation trade-offs, and patterns of sexual and viability selection on both trait size and body size. An unbiased empirical assessment of the relation between sexual selection and allometry is an essential step towards an understanding of this diversity.

Factors influencing fluoxetine-induced sexual dysfunction in female rats

PubMed Central

Adams, Sarah; Heckard, Danyeal; Hassell, James; Uphouse, Lynda

2012-01-01

Treatment with selective serotonin reuptake inhibitors, such as fluoxetine, produces sexual side effects with low sexual desire being the most prevalent effect in females. In few studies have preclinical models for such antidepressant-induced sexual dysfunction been fruitful. In the current manuscript, the effects of fluoxetine on multiple measures of female sexual motivation and sexual receptivity were examined. Ovariectomized, Fischer rats were primed with 10 μg estradiol benzoate and 500 μg progesterone. Partner preference, active investigation of the male, and measures of sexual behavior were examined after injection with 15 mg/kg fluoxetine. Factors (pretesting for sexual behavior, size of the test arena, non-contact time with a male) that differ among experiments designed to study antidepressant-induced female rat sexual dysfunction were studied. The male preference ratio was not affected by fluoxetine treatment but active investigation of the male was reduced; lordosis behavior was inhibited and pretesting for sexual receptivity amplified fluoxetine's inhibition; size of the testing arena or non-contact experience with the male had no effect. Regardless of test condition, when given the opportunity to escape from the male, fluoxetine-treated females displayed escape behavior. Measures of male preference and active investigation, but not lordosis behavior, appeared to be affected by fluoxetine's impact on activity. The collective data provided a behavioral profile of fluoxetine-induced sexual dysfunction. These findings reinforce the value of multiple measures when attempting to model antidepressant-induced female sexual dysfunction. PMID:22835821

Socio-demographic correlates of sexual behaviours: a cross sectional survey of adolescents in Imo State secondary schools.

PubMed

Nwoke, E A; Okafor, J O; Chukwuocha, U M; Nworuh, B O

2011-03-01

The study was designed to determine the socio-demographic correlates of sexual behaviours of the adolescents in Imo State secondary schools. Three objectives and three hypotheses were formulated to guide the study. A cross sectional survey design was used and sample size was 3360 (2.2%) adolescents. A structured, validated and reliable questionnaire (r = 0.79) and focus group discussion were used as the instruments for data collection. Data analysis was done using mean and ANOVA statistics. The result generally, showed that the average sexual behaviours of the adolescents were below the decision mean of 2.50 and as such the adolescents were said to be sexually inactive. In Imo State secondary schools, various family sizes did not significantly influence the sexual behaviours of the adolescents (F-cal. 2.39, F-tab. 3.00 & P > 0.05), family structure significantly influenced their sexual behaviours (F-cal. 17.78, F-tab. 3.00 & P < 0.05) and different financial strengths influenced the adolescents sexual behaviours significantly (F-cal. 22.88, F-tab. 2.37 & P < 0.05. Of great worry is that unrestricted/uncontrolled adolescents sexual behaviours may expose them to sexually transmitted infections/HIV/AIDS, unwanted pregnancies, illegal abortion and dropping out of school. Thus comprehensive sex education was recommended.

ELASTICITY, DOUBLE REFRACTION AND SWELLING OF ISOELECTRIC GELATIN

PubMed Central

Kunitz, M.

1930-01-01

Quincke's researches (1904) have demonstrated that when a 20 per cent gelatin gel is allowed to swell in water it gives rise to positive double refraction, as if the gel were under tensile stresses. If, on the other hand, the gel shrinks on being placed in alcohol it becomes negatively double refractive, as if it were compressed. But the double refraction as found by Quincke lasts only during the process of swelling or shrinking, and disappears as soon as the gel reaches a state of equilibrium. This phenomenon was investigated here and it was found that the reason for the disappearance of the double refraction is due to the fact that at equilibrium the percentage change in the size of a gel is equal in all three dimensions and the strain is therefore uniform. Double refraction persists as long as there is a difference in the elastic strain in the three dimensions of the strained material. It was found that when gels are cast on glass slides or in glass frames, so as to prevent swelling in certain directions, the double refraction produced by swelling at 6°C. persists permanently in the gel as long as it is swollen, and is proportional to the percentage change in the linear dimensions of the gel. Gels made up of various concentrations of isoelectric gelatin of less than 10 per cent when placed in dilute buffer of the same pH as that of the isoelectric point of the gelatin shrink and give rise to negative double refraction, while gels of concentrations of more than 10 per cent swell and give rise to positive double refraction. The double refraction produced in either case when divided by the percentage change in the dimensions of the gel and by its changed concentration gives a constant value both for swelling and shrinking. This constant which stands for the double refraction produced in a gel of unit concentration per unit strain is termed here the optical modulus of elasticity since it is proportional to the internal elastic stress in the swollen gelatin. It was found that the optical modulus of elasticity is the same both for gels cast on slides and in frames, although the mode of swelling is different in the two forms of gels. Gels removed from their glass supports after apparent swelling equilibrium, when placed in dilute buffer, begin to swell gradually in all three dimensions and the double refraction decreases slowly, though it persists for a long time. But the double refraction per unit change in dimension and per unit concentration still remains the same as before, thus proving that the internal elastic stress as indicated by the double refraction is brought about by the resistance of the gel itself to deformation. A study was also made on the effect of salts, acid and base on the double refraction of a 10 per cent gel during swelling. The experiments show that below M/8 salts affect very slightly the optical modulus of elasticity of the gel. At higher concentrations of salts the elasticity of the gel is reduced by some salts and increased by others, while such salts as sodium acetate and sodium and ammonium sulfates do not change the elasticity of the gels at all during swelling. The investigated salts may thus be arranged in this respect in the following approximate series: CaCl2, NaI, NaSCN, NaBr, AlCl3, NaCl, Na acetate, Na2SO4, (NH4)2SO4, Al2SO4 and MgSO4. The first five in the series decrease the elasticity while the last two in the series increase the elasticity of the gels during swelling. Acids and bases in higher concentrations exert a powerful influence on the reduction of the elasticity of the gel but in the range of pH between 2.0 and 10.0 the elasticity remains unaffected. The general conclusions to be drawn from these studies are as follows: 1. Swelling or shrinking produces elastic stresses in gels of gelatin, tensile in the first case and compressive in the second case, both being proportional to the percentage change in the dimensions of the gel. 2. Unsupported gels when immersed in aqueous solutions swell or shrink in such a manner that at equilibrium the percentage change in size is equal in all three dimensions, and the stresses become equalized throughout the gel. 3. Gels cast on glass slides or in frames when immersed in aqueous solutions swell or shrink mostly in one direction, and give rise to unidirectional stresses that can be determined accurately by measuring the double refraction produced. 4. The modulus of elasticity of swelling gelatin gels, as calculated from the double refraction measurements, is the same both for compression and for tension and is proportional to the concentration of gelatin in the gel. 5. The modulus of elasticity of gels during swelling is affected only slightly or not at all by salts at concentrations of less than M/8 and is independent of the pH in the range approximately between 2.0 and 10.0. 6. Higher concentrations of salts affect the modulus of elasticity of gelatin gels and the salts in their effectiveness may be arranged in a series similar to the known Hoffmeister series. 7. Acid and alkali have a strong reducing influence on the elastic modulus of swelling gels. 8. The swelling produced in isoelectric gelatin by salts is due primarily to a change brought about by the salts in the osmotic forces in the gel, but in high concentrations of some salts the swelling is increased by the influence of the salt on the elasticity of the gel. This agrees completely with the theory of swelling of isoelectric gelatin as developed by Northrop and the writer in former publications. 9. The studies of Loeb and the writer on the effect of salts on swelling of gelatin in acid and alkali have been in the range of concentrations of salts where the modulus of elasticity of the gelatin is practically constant, and the specific effect of the various salts has been negligible as compared with the effect of the valency of the ions. In concentrations of salts below M/4 or M/8 the Hoffmeister series plays no rôle. PMID:19872548

Evaluation of adjunctive effect of low-level laser Therapy on pain, swelling and trismus after surgical removal of impacted lower third molar: A double blind randomized clinical trial.

PubMed

Farhadi, Farrokh; Eslami, Hosein; Majidi, Alireza; Fakhrzadeh, Vahid; Ghanizadeh, Milad; KhademNeghad, Sahar

2017-09-30

Wisdom teeth remains impacted in the jaw due to several reasons and surgery of impacted wisdom teeth is one of the most common surgeries in dental clinics. Pain, swelling and trismus are the common complications after this surgery which affect quality of life. In articles, various methods are introduced to control immediate inflammatory-response associated with third-molar surgery. The aim of this study is to evaluate the adjunctive effect of low-level laser Therapy on pain, swelling and trismus after surgical removal of impacted lower third molar. This double-blind randomized controlled trial (RCT) was conducted on two groups of 24 patients (age range of 18-35) that had referred to surgical ward of Faculty of Dentistry, Tabriz University of Medical Sciences for surgery of their mandibular third molar(2015-16). All the subjects were systemically healthy and had at least one impacted mandibular third molar. After surgery, in experimental group, the laser was applied intraorally (inside the tooth socket) and extraorally (at the insertion point of the masseter muscle) immediately after surgery in contact with the target area for 25 seconds each. The laser energy was 2.5 J per area with an energy density of 5 J/ cm 2 at the surface of the probe (spot size= 0.5 cm 2 ). In the other group, as the control group, it was pretended to radiate. Trismus, pain, and swelling were evaluated on the first and seventh days after surgery. The obtained data were evaluated using SPSS 16 software and independent samples T-test. In the group where LLLT had been used, P> 0.05 was calculated for pain, swelling, and trismus on days 1 and 7 after surgery that was not statistically significant. Under limitations of this study, using low-power laser with mentioned parameters, clinically reduces pain, swelling and trismus after surgical removal of impacted mandibular wisdom, but not statistically significant.

From Evolutionary Allometry to Sexual Display: (A Reply to Holman and Bro-Jørgensen).

PubMed

Raia, Pasquale; Passaro, Federico; Carotenuto, Francesco; Meiri, Shai; Piras, Paolo

2016-08-01

Conventional wisdom holds that the complex shapes of deer antlers are produced under the sole influence of sexual selection. We questioned this view by demonstrating that trends for increased body size evolution passively yield more-complex ornaments, even in organisms where no effect of sexual selection is possible, with similar allometric slopes. Recent investigations suggest that sexual selection on antlers of larger deer species is stronger than that in smaller species; hence, the use of conspicuous antlers for display in large male deer is a secondary function driven by especially intense sexual selection on these large-bodied species. Since ancestral deer were small and had very simple antlers, such an intense selection on antlers shape was probably absent in early deer. Therefore, the evolution of complex ornaments is coupled with body size evolution, even in deer.

Penis size interacts with body shape and height to influence male attractiveness.

PubMed

Mautz, Brian S; Wong, Bob B M; Peters, Richard A; Jennions, Michael D

2013-04-23

Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male's relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits.

Penis size interacts with body shape and height to influence male attractiveness

PubMed Central

Mautz, Brian S.; Wong, Bob B. M.; Peters, Richard A.; Jennions, Michael D.

2013-01-01

Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male’s relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits. PMID:23569234

Parental and perinatal risk factors for sexual offending in men: a nationwide case-control study.

PubMed

Babchishin, K M; Seto, M C; Sariaslan, A; Lichtenstein, P; Fazel, S; Långström, N

2017-01-01

Prior studies suggest parental and perinatal risk factors are associated with later offending. It remains uncertain, however, if such risk factors are similarly related to sexual offending. We linked socio-demographic, family relations, and perinatal (obtained at birth) data from the nationwide Swedish registers from 1973 to 2009 with information on criminal convictions of cases and control subjects. Male sex offenders (n = 13 773) were matched 1:5 on birth year and county of birth in Sweden to male controls without sexual or non-sexual violent convictions. To examine risk-factor specificity for sexual offending, we also compared male violent, non-sexual offenders (n = 135 953) to controls without sexual or non-sexual violent convictions. Predictors included parental (young maternal or paternal age at son's birth, educational attainment, violent crime, psychiatric disorder, substance misuse, suicide attempt) and perinatal (number of older brothers, low Apgar score, low birth weight, being small for gestational age, congenital malformations, small head size) variables. Conditional logistic regression models found consistent patterns of statistically significant, small to moderate independent associations of parental risk factors with sons' sexual offending and non-sexual violent offending. For perinatal risk factors, patterns varied more; small for gestational age and small head size exhibited similar risk effects for both offence types whereas a higher number of older biological brothers and any congenital malformation were small, independent risk factors only for non-sexual violence. This nationwide study suggests substantial commonalities in parental and perinatal risk factors for the onset of sexual and non-sexual violent offending.

Sexual problems and post-traumatic stress disorder following sexual trauma: A meta-analytic review.

PubMed

O'Driscoll, Ciarán; Flanagan, Esther

2016-09-01

Difficulties with sex often develop following sexual trauma, yet are rarely targeted within treatment of post-traumatic stress disorder (PTSD). Where outcomes of sexual function are included, they are secondary to other measures. This review aimed to assess whether psychological treatment for PTSD (from sexual trauma) has an effect on sexual functioning. Systematic searches of MEDLINE, PsycINFO, EMBASE, and trial registers were performed. Five studies met inclusion criteria. Pre-post treatment effect sizes were also calculated. Data from four good-quality RCTs were included in the meta-analyses. These examined females (n = 799) who had experienced adult sexual trauma or child sexual abuse. Studies compared psychological treatment to control conditions, but no effect on outcomes of sexual concerns, standardized mean difference (SMD) = 0.03 and dysfunctional sexual behaviour, SMD = 0.02, was found. Pre-post treatment effect sizes were small to medium (SMD = 0.36 and 0.47, respectively). While firm conclusions cannot be drawn, the available evidence suggests that psychological treatment for PTSD has no effect on sexual problems. Pre-post effects indicate some improvement over the course of treatment, which may be strengthened if treatment actively targeted sexual problems. The paucity of evidence in this area suggests that there is substantial need for further research in order to establish a set of evidence-based guidelines for practitioners implementing treatment in this area. The measurement of sexual problems is overlooked in psychological treatment RCTs for sexual trauma. Current treatments for post-traumatic stress disorder (PTSD) from sexual trauma do not appear to be addressing sexual problems. Integrated treatments for comorbid sexual problems and PTSD treatment may be warranted. It is imperative that in future, RCTs that examine people with PTSD from sexual trauma use outcomes of sexual problems. © 2015 The British Psychological Society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi-chune, Y.; Liu, L.

The evaporation, heating, and burning of single coal-water slurry droplets are studied. The coal selected in this study is Pittsburgh Seam number 8 coal which is a medium volatile caking bituminous coal. The droplet is suspended on a microthermocouple and exposed to a hot gas stream. Temperature measurement and microscopic observation are performed in the parametric studies. The duration of water evaporation in CWS droplets decreases with the reduction of the droplet size, increasing of coal weight fraction, and increasing of gas temperature and velocity. The duration of heat-up is always significant due to the agglomeration. The CWS droplets aremore » generally observed to swell like popcorn during heating. A model for the formation of the popped swelling is proposed and discussed.« less

Results of the freeze resistance test, swelling index and coefficient of permeability of finegrained mining waste reinforced with cements

NASA Astrophysics Data System (ADS)

Morman, Justyna

2018-04-01

The article presents the result of laboratory tests for mining waste with grain size of 0 to 2 mm stabilized with cement. Used for stabilization of cement CEM I 42.5 R and blast furnace cement CEM III / A 42.5N - LH / HSR / NA and a plasticizer sealant. Cement was added to the mining waste test in the proportions of 5 - 8% in relation to the skeleton's weight. For the cemented samples, the freeze resistance test, swelling index, coefficient of permeability and pH of water leachate were tested. The addition of a cement binder resulted in diminishing the water permeability of mining waste and limiting the leaching of fine particles from the material.

Nuclear-radiation-actuated valve. [Patent application; for increasing coolant flow to blanket

DOEpatents

Christiansen, D.W.; Schively, D.P.

1982-01-19

The present invention relates to a breeder reactor blanket fuel assembly coolant system valve which increases coolant flow to the blanket fuel assembly to minimize long-term temperature increases caused by fission of fissile fuel created from fertile fuel through operation of the breeder reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

Thermo-responsive and compression properties of TEMPO-oxidized cellulose nanofiber-modified PNIPAm hydrogels.

PubMed

Wei, Jinguang; Chen, Yufei; Liu, Hongzhi; Du, Chungui; Yu, Huilong; Zhou, Zhongxi

2016-08-20

In this study, TEMPO-oxidized bamboo cellulose nanofibers (TO-CNF) with anionic carboxylate groups on the surfaces were in-situ incorporated into poly(N-isopropylacrylamide) (PNIPAm) matrix to improve its thermo-responsive and mechanical properties during the polymerization. The microstructure, swelling behaviors, and compressive strength of resultant PNIPAm composite hydrogels with varying contents of TO-CNFs (0-10wt%) were then examined, respectively. Modified hydrogels exhibited the similar light transparency to pure PNIPAm one due to the formation of semi-IPN structure between PNIPAm and TO-CNF. FT-IR spectra demonstrated that the presence of TO-CNF did not alter the position of characteristic peaks associated with PNIPAm. SEM observation suggested that the pore size of PNIPAm hydrogels was markedly increased after the incorporation of TO-CNF. Also, the composite hydrogels showed superior swelling behavior and much improved compression properties with respect to pure PNIPAm one. Thus, TO-CNF appeared to be a "green" nanofiller that can simultaneously improve swelling and mechanical properties of PNIPAm hydrogel. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sexual Dimorphism and Allometric Effects Associated With the Wing Shape of Seven Moth Species of Sphingidae (Lepidoptera: Bombycoidea)

PubMed Central

de Camargo, Nícholas Ferreira; Corrêa, Danilo do Carmo Vieira; de Camargo, Amabílio J. Aires; Diniz, Ivone Rezende

2015-01-01

Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females). PMID:26206895

Sexual selection on female ornaments in the sex-role-reversed Gulf pipefish (Syngnathus scovelli).

PubMed

Flanagan, S P; Johnson, J B; Rose, E; Jones, A G

2014-11-01

Understanding how selection acts on traits individually and in combination is an important step in deciphering the mechanisms driving evolutionary change, but for most species, and especially those in which sexual selection acts more strongly on females than on males, we have no estimates of selection coefficients pertaining to the multivariate sexually selected phenotype. Here, we use a laboratory-based mesocosm experiment to quantify pre- and post-mating selection on female secondary sexual traits in the Gulf pipefish (Syngnathus scovelli), a sexually dimorphic, sex-role-reversed species in which ornamented females compete for access to choosy males. We calculate selection differentials and gradients on female traits, including ornament area, ornament number and body size for three episodes of selection related to female reproductive success (number of mates, number of eggs transferred and number of surviving embryos). Selection is strong on both ornament area and ornament size, and the majority of selection occurs during the premating episode of selection. Interestingly, selection on female body size, which has been detected in previous studies of Gulf pipefish, appears to be indirect, as evidenced by a multivariate analysis of selection gradients. Our results show that sexual selection favours either many bands or larger bands in female Gulf pipefish. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Sexually Monomorphic Maps and Dimorphic Responses in Rat Genital Cortex.

PubMed

Lenschow, Constanze; Copley, Sean; Gardiner, Jayne M; Talbot, Zoe N; Vitenzon, Ariel; Brecht, Michael

2016-01-11

Mammalian external genitals show sexual dimorphism [1, 2] and can change size and shape upon sexual arousal. Genitals feature prominently in the oldest pieces of figural art [3] and phallic depictions of penises informed psychoanalytic thought about sexuality [4, 5]. Despite this longstanding interest, the neural representations of genitals are still poorly understood [6]. In somatosensory cortex specifically, many studies did not detect any cortical representation of genitals [7-9]. Studies in humans debate whether genitals are represented displaced below the foot of the cortical body map [10-12] or whether they are represented somatotopically [13-15]. We wondered what a high-resolution mapping of genital representations might tell us about the sexual differentiation of the mammalian brain. We identified genital responses in rat somatosensory cortex in a region previously assigned as arm/leg cortex. Genital responses were more common in males than in females. Despite such response dimorphism, we observed a stunning anatomical monomorphism of cortical penis and clitoris input maps revealed by cytochrome-oxidase-staining of cortical layer 4. Genital representations were somatotopic and bilaterally symmetric, and their relative size increased markedly during puberty. Size, shape, and erect posture give the cortical penis representation a phallic appearance pointing to a role in sexually aroused states. Cortical genital neurons showed unusual multi-body-part responses and sexually dimorphic receptive fields. Specifically, genital neurons were co-activated by distant body regions, which are touched during mounting in the respective sex. Genital maps indicate a deep homology of penis and clitoris representations in line with a fundamentally bi-sexual layout [16] of the vertebrate brain. Copyright © 2016 Elsevier Ltd. All rights reserved.

Homophobia Is Related to a Low Interest in Sexuality in General: An Analysis of Pupillometric Evoked Responses.

PubMed

Cheval, Boris; Grob, Emmanuelle; Chanal, Julien; Ghisletta, Paolo; Bianchi-Demicheli, Francesco; Radel, Remi

2016-10-01

A recent study by Cheval et al (J Sex Med 2016;13:825-834) found that individuals high in homophobia look significantly less long at sex-related photographs, regardless of their nature (ie, homosexual or heterosexual). Because viewing time is under some conscious control, this result could indicate that individuals high in homophobia have a low sexual interest in any sexual stimuli or are consciously motivated to avoid sexual material in line with their conscious values. To determine the mechanism underlying shorter viewing time of sex-related photographs in individuals high in homophobia using pupil dilatation, which is considered a spontaneous, unconscious, and uncontrollable index of sexual interest. Heterosexual men (N = 36) completed a questionnaire assessing their level of homo-negativity and then performed a picture-viewing task with simultaneous eye-tracking recording to assess their pupillary responses to the presentation of sexually related or neutral photographs. Non-linear mixed models were carried out to fit the individual non-linear trajectories of pupillary reaction. Different parameters were obtained including the final asymptote of the pupillary response. Results showed that the final pupil size of men high in homophobia increased significantly less to the presentation of sex-related images (ie, heterosexual and homosexual) than the pupil size of men low in homophobia. In contrast, no significant difference in the final pupil size reaction toward homosexual images (vs heterosexual images) emerged between men high and men low in homophobia. Theoretically, these findings reinforce the necessity to consider that homophobia might reflect concerns about sexuality in general and not homosexuality in particular. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Influence of layer charge and charge distribution of smectites on the flow behaviour and swelling of bentonites

USGS Publications Warehouse

Christidis, G.E.; Blum, A.E.; Eberl, D.D.

2006-01-01

The influence of layer charge and charge distribution of dioctahedral smectites on the rheological and swelling properties of bentonites is examined. Layer charge and charge distribution were determined by XRD using the LayerCharge program [Christidis, G.E., Eberl, D.D., 2003. Determination of layer charge characteristics of smectites. Clays Clay Miner. 51, 644-655.]. The rheological properties were determined, after sodium exchange using the optimum amount of Na2CO3, from free swelling tests. Rheological properties were determined using 6.42% suspensions according to industrial practice. In smectites with layer charges of - 0.425 to - 0.470 per half formula unit (phfu), layer charge is inversely correlated with free swelling, viscosity, gel strength, yield strength and thixotropic behaviour. In these smectites, the rheological properties are directly associated with the proportion of low charge layers. By contrast, in low charge and high charge smectites there is no systematic relation between layer charge or the proportion of low charge layers and rheological properties. However, low charge smectites yield more viscous suspensions and swell more than high charge smectites. The rheological properties of bentonites also are affected by the proportion of tetrahedral charge (i.e. beidellitic charge), by the existence of fine-grained minerals having clay size, such as opal-CT and to a lesser degree by the ionic strength and the pH of the suspension. A new method for classification of smectites according to the layer charge based on the XRD characteristics of smecites is proposed, that also is consistent with variations in rheological properties. In this classification scheme the term smectites with intermediate layer charge is proposed. ?? 2006 Elsevier B.V. All rights reserved.

Effect of synthesized ZnO nanoparticles on thermal conductivity and mechanical properties of natural rubber

NASA Astrophysics Data System (ADS)

Suntako, R.

2018-01-01

Zinc oxide (ZnO) is widely used in rubber industry as a cure activator for rubber vulcanization. In this work, comparison of cure characteristic, mechanical properties, thermal conductivity and volume swell testing in oil no.1 and oil no.3 between natural rubber (NR) filled synthesized ZnO nanoparticles (sZnO) by precipitation method and NR filled conventional ZnO (cZnO). The particle size of sZnO is 41.50 nm and specific area of 27.92 m2/g, the particle size of cZnO is 312.92 nm and specific surface area of 1.35 m2/g. It has been found that NR filled sZnO not only improves rubber mechanical properties, volume swell testing but also improves thermal conductivity and better than NR filled cZnO. Thermal conductivity of NR filled sZnO increases by 10.34%, 12.90% and 20.00%, respectively when compared with NR filled cZnO in same loading content (various concentrations of ZnO at 5, 8 and 10 parts per hundred parts of rubber). This is due to small particle size and large specific surface area of sZnO which lead to an increase in crosslinking in rubber chain and enhance heat transfer performance.

Genome size variation affects song attractiveness in grasshoppers: evidence for sexual selection against large genomes.

PubMed

Schielzeth, Holger; Streitner, Corinna; Lampe, Ulrike; Franzke, Alexandra; Reinhold, Klaus

2014-12-01

Genome size is largely uncorrelated to organismal complexity and adaptive scenarios. Genetic drift as well as intragenomic conflict have been put forward to explain this observation. We here study the impact of genome size on sexual attractiveness in the bow-winged grasshopper Chorthippus biguttulus. Grasshoppers show particularly large variation in genome size due to the high prevalence of supernumerary chromosomes that are considered (mildly) selfish, as evidenced by non-Mendelian inheritance and fitness costs if present in high numbers. We ranked male grasshoppers by song characteristics that are known to affect female preferences in this species and scored genome sizes of attractive and unattractive individuals from the extremes of this distribution. We find that attractive singers have significantly smaller genomes, demonstrating that genome size is reflected in male courtship songs and that females prefer songs of males with small genomes. Such a genome size dependent mate preference effectively selects against selfish genetic elements that tend to increase genome size. The data therefore provide a novel example of how sexual selection can reinforce natural selection and can act as an agent in an intragenomic arms race. Furthermore, our findings indicate an underappreciated route of how choosy females could gain indirect benefits. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Mondor's disease of the penis following a long-haul flight.

PubMed

Day, S; Bingham, J S

2005-07-01

Mondor's disease of the penis, otherwise known as superficial thrombophlebitis (STP) or thrombosis of the dorsal vein, is an under-reported benign condition, the aetiology of which is poorly understood. It is characterized by a sudden, indurated swelling of the vein, often occurring after vigorous sexual activity. We report a case of Mondor's disease occurring 24 h following a 15-h flight. This gentleman also reported a history of STP of his left lower limb varicose veins following a similar-length flight three years previously. In the absence of any other clear predisposing factor, we propose long-haul flight as an important factor contributing to the development of dorsal vein thrombosis.

To what extent clay mineralogy affects soil aggregation? Consequences for soil organic matter stabilization

NASA Astrophysics Data System (ADS)

Fernandez-Ugalde, O.; Barré, P.; Hubert, F.; Virto, I.; Chenu, C.; Ferrage, E.; Caner, L.

2012-12-01

Aggregation is a key process for soil functioning as it influences C storage, vulnerability to erosion and water holding capacity. While the influence of soil organic C on aggregation has been documented, much less is known about the role of soil mineralogy. Soils usually contain a mixture of clay minerals with contrasted surface properties, which should result on different abilities of clay minerals to aggregation. We took advantage of the intrinsic mineral heterogeneity of a temperate Luvisol to compare the role of clay minerals (illite, smectite, kaolinite, and mixed-layer illite-smectite) in aggregation. In a first step, grassland and tilled soil samples were fractionated in water in aggregate-size classes according to the hierarchical model of aggregation (Tisdall and Oades, 1982). Clay mineralogy and organic C in the aggregate-size classes were analyzed. The results showed that interstratified minerals containing swelling phases accumulated in aggregated fractions (>2 μm) compared to free clay fractions (<2 μm) in the two land-uses. The accumulation increased from large macro-aggregates (>500 μm) to micro-aggregates (50-250 μm). C concentration and C/N ratio followed the opposite trend. These results constitute a clay mineral-based evidence for the hierarchical model of aggregation, which postulates an increasing importance of the reactivity of clay minerals in the formation of micro-aggregates compared to larger aggregates. In the latter aggregates, formation relies on the physical enmeshment of particles by fungal hyphae, and root and microbial exudates. In a second step, micro-aggregates from the tilled soil samples were submitted to increasingly disaggregating treatments by sonication to evaluate the link between their water stability and clay mineralogy. Micro-aggregates with increasing stability showed an increase of interstratified minerals containing swelling phases and C concentration for low intensities of disaggregation (from 0 to 5 J mL-1). This suggests that swelling phases promote their stability. Swelling phases and organic C decreased for greater intensities of disaggregation. These results and the SEM images taken at different disaggregation intensities indicate that when increasing disaggregation intensity above 5 J mL-1, the recovered material consists on sand particles covered by physical coatings of illite and kaolinite. Our results show that different clay minerals have different contribution to soil aggregation. Swelling phases are especially important for water-stable aggregates formation, whereas illite and kaolinite can either contribute to aggregation or been coated to sand grains in "mineral aggregates", without porosity and organic C protection capability. In conclusion, soils with large proportion of swelling clay minerals have greater potential for carbon storage by occlusion in aggregates and greater resistance to erosion. Tisdall JM, Oades JM (1982) Organic matter and water-stable aggregates in soils. J Soil Sci 62: 141-163.

As Budgets Swell, Spending Choices Get New Scrutiny

ERIC Educational Resources Information Center

McNeil, Michele

2007-01-01

When lawmakers in Arkansas increased school funding by more than $700 million over the past three years to improve student achievement, they wanted the money to be spent on instructional coaches for teachers, tutors for struggling students, and smaller class sizes in reading, math, and science. However--in what could prove a cautionary tale for…

Coiling of a vulvar arterio-venous malformation.

PubMed

Van der Woude, Daisy Adriana Annejan; Stegeman, Marjan; Seelen, Jan L

2011-12-01

The authors report the case of a 13-year-old girl with a painful vulvar swelling and abnormal vaginal bleeding, increasing in size after trauma. With MRI (GE Signa HDx 1.5 Tesla), it is diagnosed as an arterio-venous malformation arising from the left superior femoral artery. It is treated by embolisation using a coil.

Characterizing sexual health resources on college campuses.

PubMed

Eisenberg, Marla E; Lechner, Kate E; Frerich, Ellen A; Lust, Katherine A; Garcia, Carolyn M

2012-10-01

This observational study describes the development of the college resources and sexual health inventory, the profile of sexual health promotion resources at participating colleges, and comparisons of resources across several college characteristics. 28 diverse college campuses in one Midwestern state participated. 10 domains were assessed, including characteristics of campus health services (e.g. convenience), condom programs, sexual health information, communication about resources, sexual violence resources and gay/lesbian/bisexual student resources. Scores for each measure reflected the presence or extent of each resource. Summary scores were created for the overall level of sexual health resources and for each domain. T tests and ANOVAs were used to compare resources at 2-year versus 4-year colleges, public versus private sectors, metro versus non-metro locations, and across enrollment size. Inventory scores ranged from 6 to 53. 4-year colleges offered significantly more resources than 2-year; resource levels were statistically similar across location and enrollment size. Subsequent analyses comparing campuses with and without a health center indicated that several resources which were not inherently tied to a clinic nonetheless differed significantly with having a health center. Colleges without this resource could position sexual health resources in other offices or departments or provide referrals to sexual health resources in the broader community.

Electrostatic swelling of bicontinuous cubic lipid phases.

PubMed

Tyler, Arwen I I; Barriga, Hanna M G; Parsons, Edward S; McCarthy, Nicola L C; Ces, Oscar; Law, Robert V; Seddon, John M; Brooks, Nicholas J

2015-04-28

Lipid bicontinuous cubic phases have attracted enormous interest as bio-compatible scaffolds for use in a wide range of applications including membrane protein crystallisation, drug delivery and biosensing. One of the major bottlenecks that has hindered exploitation of these structures is an inability to create targeted highly swollen bicontinuous cubic structures with large and tunable pore sizes. In contrast, cubic structures found in vivo have periodicities approaching the micron scale. We have been able to engineer and control highly swollen bicontinuous cubic phases of spacegroup Im3m containing only lipids by (a) increasing the bilayer stiffness by adding cholesterol and (b) inducing electrostatic repulsion across the water channels by addition of anionic lipids to monoolein. By controlling the composition of the ternary mixtures we have been able to achieve lattice parameters up to 470 Å, which is 5 times that observed in pure monoolein and nearly twice the size of any lipidic cubic phase reported previously. These lattice parameters significantly exceed the predicted maximum swelling for bicontinuous cubic lipid structures, which suggest that thermal fluctuations should destroy such phases for lattice parameters larger than 300 Å.

Urinary C-peptide levels in male bonobos (Pan paniscus) are related to party size and rank but not to mate competition.

PubMed

Surbeck, Martin; Deschner, Tobias; Behringer, Verena; Hohmann, Gottfried

2015-05-01

Within- and between-species variation in male mating strategies has been attributed to a multitude of factors including male competitive ability and the distribution of fertile females across space and time. Differences in energy balance across and within males allow for the identification of some of the trade-offs associated with certain social and mating strategies. Bonobos live in groups with a high degree of fission-fusion dynamics, there is co-dominance between the sexes and a linear dominance hierarchy among males. Males compete over access to females, breeding is aseasonal, and females exhibit sexual swellings over extended time periods. In this study we use urinary C-peptide (UCP) levels in male bonobos (Pan paniscus) obtained from 260 urine samples from a wild bonobo community, to quantify male energy balance during mate competition and levels of gregariousness in the species. Although high ranking males are more aggressive, spend more time in proximity to maximally tumescent females, and have higher mating frequencies, we found no indication that mate guarding or mate competition affected male energy balance. Our results showed a positive correlation between monthly mean UCP levels and mean party size. When traveling in large parties, high ranking males had higher UCP levels than those of the low ranking males. These results support the hypothesis that patterns of fission-fusion dynamics in bonobos are either linked to energy availability in the environment or to the energetic costs of foraging. The finding of a rank-bias in UCP levels in larger parties could also reflect an increase in contest competition among males over access to food. Copyright © 2015. Published by Elsevier Inc.

Multivariate Meta-Analysis of Brain-Mass Correlations in Eutherian Mammals

PubMed Central

Steinhausen, Charlene; Zehl, Lyuba; Haas-Rioth, Michaela; Morcinek, Kerstin; Walkowiak, Wolfgang; Huggenberger, Stefan

2016-01-01

The general assumption that brain size differences are an adequate proxy for subtler differences in brain organization turned neurobiologists toward the question why some groups of mammals such as primates, elephants, and whales have such remarkably large brains. In this meta-analysis, an extensive sample of eutherian mammals (115 species distributed in 14 orders) provided data about several different biological traits and measures of brain size such as absolute brain mass (AB), relative brain mass (RB; quotient from AB and body mass), and encephalization quotient (EQ). These data were analyzed by established multivariate statistics without taking specific phylogenetic information into account. Species with high AB tend to (1) feed on protein-rich nutrition, (2) have a long lifespan, (3) delayed sexual maturity, and (4) long and rare pregnancies with small litter sizes. Animals with high RB usually have (1) a short life span, (2) reach sexual maturity early, and (3) have short and frequent gestations. Moreover, males of species with high RB also have few potential sexual partners. In contrast, animals with high EQs have (1) a high number of potential sexual partners, (2) delayed sexual maturity, and (3) rare gestations with small litter sizes. Based on these correlations, we conclude that Eutheria with either high AB or high EQ occupy positions at the top of the network of food chains (high trophic levels). Eutheria of low trophic levels can develop a high RB only if they have small body masses. PMID:27746724

Prevention of Child Sexual Abuse Victimization: A Meta Analysis of School Programs.

ERIC Educational Resources Information Center

Rispens, Jan; Aleman, Andre; Goudena, Paul P.

1997-01-01

Meta-analysis of 16 evaluation studies of school programs aimed at the prevention of child sexual abuse victimization found significant and considerable mean postintervention and follow-up effect sizes, indicating that the programs were effective in teaching children sexual abuse concepts and self-protection skills. Program duration and content…

The nature of allometry in an exaggerated trait: The postocular flange in Platyneuromus Weele (Insecta: Megaloptera)

PubMed Central

Ramírez-Ponce, Andrés; Garfias-Lozano, Gabriela; Contreras-Ramos, Atilano

2017-01-01

The origin and function of exaggerated traits exhibited by a great number of species with sexual dimorphism remain largely unexplored. The usual model considered as the evolutionary mechanism for the development of these structures is sexual selection. The nature of growth of the postocular flange (POF) in three species of the dobsonfly genus Platyneuromus (Megaloptera, Corydalidae, Corydalinae) is analyzed to explore sexual size dimorphism and allometric scaling. Results involve positive allometry of POF in males of two species, and negative allometry in males of one species, in general with a female-biased sexual dimorphism. We suggest an ancestral condition of dual incipient ornamentation in Platyneuromus, with a subsequent departure of size and shape of POF in males, triggered by sexual selection. Different sexual selection intensities may explain the parallel or divergent growth of POF within the scheme of dual ornamentation. Empirical behavioral data as well as a phylogenetic framework are necessary to clarify possible causes of phenotypic development, time of origin, and evolution of the POF. PMID:28212437

Superficial Dorsal Vein Injury/Thrombosis Presenting as False Penile Fracture Requiring Dorsal Venous Ligation

PubMed Central

Rafiei, Arash; Hakky, Tariq S; Martinez, Daniel; Parker, Justin; Carrion, Rafael

2014-01-01

Introduction Conditions mimicking penile fracture are extremely rare and have been seldom described. Aim To describe a patient with false penile fracture who presented with superficial dorsal vein injury/thrombosis managed with ligation. Methods A 33-year-old male presented with penile swelling and ecchymosis after intercourse. A penile ultrasound demonstrated a thrombosed superficial dorsal vein but also questionable fracture of the tunica albuginea. As the thrombus was expanding, he was emergently taken to the operating room for exploration and required only dorsal venous ligation. Results Postoperatively, patient's Sexual Health Inventory for Men score was 23, and he had no issues with erections or sexual intercourse. Conclusion Early exploration of patients with suspected penile fracture provides excellent results with maintenance of erectile function. Also, in the setting of dorsal vein thrombosis, ligation preserves the integrity of the penile tissues and avoids unnecessary complications from conservative management. Rafiei A, Hakky TS, Martinez D, Parker J, and Carrion R. Superficial dorsal vein injury/thrombosis presenting as false penile fracture requiring dorsal venous ligation. PMID:25548650

Endocrine changes in male stumptailed macaques (Macaca arctoides) as a response to odor stimulation with vaginal secretions.

PubMed

Cerda-Molina, Ana Lilia; Hernández-López, Leonor; Chavira, Roberto; Cárdenas, Mario; Paez-Ponce, Denisse; Cervantes-De la Luz, Harry; Mondragón-Ceballos, Ricardo

2006-01-01

In mammalian species, social chemosignals are important in modulating endocrine reproductive functions. In nonhuman primates, previous studies have described a high frequency of mounting behavior by females in the follicular and periovulatory phases of the menstrual cycle. Stumptailed macaque females do not signal receptivity by means of sexual swellings, as do others macaques, therefore providing a good model in which to study chemical signaling of reproductive status. We exposed anesthetized stumptailed males to vaginal secretions of either late follicular or menses phase or to saline solution to determine the endocrine changes promoting male sexual behavior. In males exposed to follicular secretions, plasma testosterone concentrations were sustained up to 120 min after exposure. Such an effect was not observed in animals exposed to menses or saline odor sources. A luteinizing hormone surge, occurring 30 minutes after exposure to late follicular phase secretion swabs, preceded this sustained testosterone effect. The fact that late follicular scents induce sustained testosterone concentrations provides support to the idea that stumptailed males draw information concerning female reproductive status from the female's vaginal odor.

Developmental Environment Effects on Sexual Selection in Male and Female Drosophila melanogaster

PubMed Central

Morimoto, Juliano; Pizzari, Tommaso; Wigby, Stuart

2016-01-01

The developmental environment can potentially alter the adult social environment and influence traits targeted by sexual selection such as body size. In this study, we manipulated larval density in male and female Drosophila melanogaster, which results in distinct adult size phenotypes–high (low) densities for small (large) adults–and measured sexual selection in experimental groups consisting of adult males and females from high, low, or a mixture of low and high larval densities. Overall, large adult females (those reared at low larval density) had more matings, more mates and produced more offspring than small females (those reared at high larval density). The number of offspring produced by females was positively associated with their number of mates (i.e. there was a positive female Bateman gradient) in social groups where female size was experimentally varied, likely due to the covariance between female productivity and mating rate. For males, we found evidence that the larval environment affected the relative importance of sexual selection via mate number (Bateman gradients), mate productivity, paternity share, and their covariances. Mate number and mate productivity were significantly reduced for small males in social environments where males were of mixed sizes, versus social environments where all males were small, suggesting that social heterogeneity altered selection on this subset of males. Males are commonly assumed to benefit from mating with large females, but in contrast to expectations we found that in groups where both the male and female size varied, males did not gain more offspring per mating with large females. Collectively, our results indicate sex-specific effects of the developmental environment on the operation of sexual selection, via both the phenotype of individuals, and the phenotype of their competitors and mates. PMID:27167120

Irradiation behaviour of the large grained UO{sub 2} fuel pellet in the transient conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosaka, Yuji; Watanabe, Seiichi; Arakawa, Yasushi

2007-07-01

In order to achieve a high duty fuel rod design, it is the key issue to suppress the fission gas release from the view point of the fuel rod inner pressure design. The large grain UO{sub 2} pellet is one of the candidates to meet such a requirement by reducing the fission gas release especially at high power and/or high burnup. We have demonstrated the fuel performance of the large grain pellet in the PWR irradiation conditions, which was fabricated with no additive but with active UO{sub 2} powder through the conventional pelletizing process for the normal grain size pellet.more » According to the mechanism of the fission gas retention, there may be a concern about the larger gas bubble swelling of the large grain pellet at the power transient conditions which may increase the potential of the PCMI failure. In this paper, we focus on the differences of the dimensional change in comparison among the pellets with the different grain sizes at the power transient conditions. The power ramp tests were carried out on the high burnup fuel rods of normal and large grain pellet with no additive, which had been irradiated in the PWR conditions up to around 60 GWd/t at peak position. The detailed PIE results revealed that the volume increment due to the power ramp clearly showed the dependence on the grain size as well as the fission gas release and suggested that the larger grain with no additive may suppress the gas bubble swelling at the power transient conditions. According to the experimental results, it is concluded that the large grain pellet with no additive does not deteriorate the irradiation performance during the power transient conditions from the view point of the gas bubble swelling. (authors)« less

The engineering significance of shrinkage and swelling soils in blast damage investigations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vitton, S.J.; Harris, W.W.

1996-12-01

In the US each year it has been estimated that expansive soils cause approximately $9.0 billion in damage to buildings, roads, airports, and other facilities. This figure alone exceeds the damage estimate for earthquakes, floods, tornadoes, and hurricanes combined. Unfortunately, some cases of expansive soil damage (swelling) are blamed on rock blasting operations if the blasting operations are located within the immediate area. While simple tests, such as the Atterberg limits test, can characterize a soil as expansive, it does not necessarily answer the question whether the foundation soils are causing distresses to a structure. In particular, it appears thatmore » once a soil has been labeled as nonexpansive it is no longer considered as a problem soil, in which case blast vibrations become the prime suspect. It should be emphasized, however, that even non-plastic soils, those soils with low to nonexistent plastic indexes, can exhibit significant shrinkage characteristics that can result in significant damage to structures. While expansive soil is a function of the mineralogy of the soil particles, i.e., swelling clay minerals, shrinkage is caused by the loss of moisture from soil as capillary pressures exceed the cohesion or tensile strength and is therefore a function of the soils particle size and its pore size distribution. This is a significant problem for all fine grained soils regardless of the soil`s mineralogy. It`s particularly important for regions of the US that typically have a positive water balance but experience significant drought periods when soil moisture is lost.« less

Characteristics of venom allergic reactions in Turkish beekeepers and alternative treatment modalities.

PubMed

Çelıksoy, Mehmet Halil; Sancak, Recep; Söğüt, Ayhan; Güner, Sükrü Nail; Korkmaz, Ali

2014-07-01

The objective of this work was to determine the characteristics of allergic reactions that may occur after a bee sting and alternative treatment methods in Turkish beekeepers. A written questionnaire was administered to beekeepers from the Ordu, Samsun, Sinop, Amasya, and Çorum provinces located in the Central Black Sea Region of Turkey. The study included 301 beekeepers, 295 (98%) of whom were male. Their mean age was 48.2 ± 11.5 years. The mean beekeeping duration was 15.3 ± 10.5 years. A total of 270 participants (89.9%) had a history of bee stings in the previous 12 months. Systemic reactions, large local reactions, and local reactions were seen in 21 (6.9%), 193 (64.1%), and 12 (4.0%) beekeepers, respectively. The face was the most frequently stung body site, and swelling generally occurred in the eyelids. The size of the swellings decreased within 12 to 24 hours in 259 (86.1%) beekeepers. The size of the swellings was 1 × 2 cm in diameter in 157 (52.2%) beekeepers. Natural protection against bee stings had developed by 12 months in 140 (46.5%) beekeepers. In total, 61.5% of the beekeepers applied alternative treatments (eg, garlic, onion water, yogurt), whereas 14.0% (3/21) were admitted to a hospital with a systemic reaction. In total, 10.6% and 14.2% of beekeepers were aware of adrenaline auto-injector and venom immunotherapy, respectively. This study indicates insufficient knowledge and attitudes among Turkish beekeepers regarding bee sting reactions. © 2014 ARS-AAOA, LLC.

Health Concerns for Gay and Lesbian Teens

MedlinePlus

... Text Size Email Print Share Health Concerns for Gay and Lesbian Teens Page Content Article Body Sexual activity Most teens, whether they are gay, lesbian, bisexual , or straight, are not sexually active. ...

Quantitative genetic correlation between trait and preference supports a sexually selected sperm process

PubMed Central

Simmons, Leigh W.; Kotiaho, Janne S.

2007-01-01

Sperm show patterns of rapid and divergent evolution that are characteristic of sexual selection. Sperm competition has been proposed as an important selective agent in the evolution of sperm morphology. However, several comparative analyses have revealed evolutionary associations between sperm length and female reproductive tract morphology that suggest patterns of male–female coevolution. In the dung beetle Onthophagus taurus, males with short sperm have a fertilization advantage that depends on the size of the female's sperm storage organ, the spermatheca; large spermathecae select for short sperm. Sperm length is heritable and is genetically correlated with male condition. Here we report significant additive genetic variation and heritability for spermatheca size and genetic covariance between spermatheca size and sperm length predicted by both the “good-sperm” and “sexy-sperm” models of postcopulatory female preference. Our data thus provide quantitative genetic support for the role of a sexually selected sperm process in the evolutionary divergence of sperm morphology, in much the same manner as precopulatory female preferences drive the evolutionary divergence of male secondary sexual traits. PMID:17921254

Thinking big: the effect of sexually objectifying music videos on bodily self-perception in young women.

PubMed

Mischner, Isabelle H S; van Schie, Hein T; Wigboldus, Daniël H J; van Baaren, Rick B; Engels, Rutger C M E

2013-01-01

The present study investigated the effect of sexually objectifying music video exposure on young women's implicit bodily self-perception and the moderating role of self-esteem. Fifty-six college women of normal weight were either exposed to three sexually objectifying music videos or three neutral music videos. Perceived and ideal body size were measured both before and after video exposure, using horizontally stretched and compressed photographs of the participant's own body in swimming garment. As expected, only women low (but not high) in self-esteem were negatively affected by the sexually objectifying content of the music videos: they perceived themselves as bigger and showed an increased discrepancy between their perceived and ideal body size after video exposure. The neutral music videos did not influence women's bodily self-perceptions. These findings suggest that body image is a flexible construct, and that high self-esteem can protect women against the adverse effects of sexually objectifying media. Copyright © 2012 Elsevier Ltd. All rights reserved.

Stability of upper face sexual dimorphism in central European populations (Czech Republic) during the modern age.

PubMed

Bejdová, Šárka; Dupej, Ján; Krajíček, Václav; Velemínská, Jana; Velemínský, Petr

2018-01-01

One of the most fundamental issues in forensic anthropology is the determination of sex and population affinity based on various skeletal elements. Therefore, we compared the sexual dimorphism of the upper facial skeleton from a recent Czech population (twenty-first century) with that of a population from Early Modern Age Bohemia (sixteenth to eighteenth centuries). Methods of geometric morphometrics were applied. According to the results, sexual dimorphism in terms of size, shape, and form was statistically significant in both populations. The best results of sex estimation originated from analyses of form. Thus, both size and shape differences should be taken into account for determination of the sex. The accuracy of prediction achieved 91.1% for individuals in the recent population and 87.5% for individuals from the early modern population. Only minor differences were found between sexual dimorphism in the studied populations. We conclude that sexual dimorphism of the upper facial skeleton is stable during the relatively short time period.

A change in competitive context reverses sexual selection on male size.

PubMed

Kasumovic, M M; Andrade, M C B

2009-02-01

In studies of sexual selection, larger size is often argued to increase male fitness, and relatively smaller males are explained by genetic and/or environmental variation. We demonstrate that a size-development life-history trade-off could underlie the maintenance of a broad, unimodal distribution of size in male redback spiders (Latrodectus hasselti). Larger males are superior in direct competition, but redback males mature rapidly at small size in the presence of females. In field enclosures, we simulated two competitive contexts favouring development of divergent male sizes. Relatively smaller males lost when competing directly, but had 10 times higher fitness than relatively larger males when given the temporal advantage of rapid development. Linear selection gradients confirmed the reversal of selection on size, showing that it is critical to consider life-history decisions underlying the development of traits related to fitness.

Reversibly pH-responsive polyurethane membranes for on-demand intravaginal drug delivery.

PubMed

Kim, Seungil; Chen, Yufei; Ho, Emmanuel A; Liu, Song

2017-01-01

To provide better protection for women against sexually transmitted infections, on-demand intravaginal drug delivery was attempted by synthesizing reversibly pH-sensitive polyether-polyurethane copolymers using poly(ethylene glycol) (PEG) and 1,4-bis(2-hydroxyethyl)piperazine (HEP). Chemical structure and thermo-characteristics of the synthesized polyurethanes were confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), 1 H-nuclear magnetic resonance ( 1 H-NMR), and melting point testing. Membranes were cast by solvent evaporation method using the prepared pH-sensitive polyurethanes. The impact of varying pH on membrane swelling and surface morphology was evaluated via swelling ratio change and scanning electron microscopy (SEM). The prepared pH-responsive membranes showed two times higher swelling ratio at pH 4 than pH 7 and pH-triggered switchable surface morphology change. The anionic anti-inflammatory drug diclofenac sodium (NaDF) was used as a model compound for release studies. The prepared pH-responsive polyurethane membranes allowed continuous NaDF release for 24h and around 20% release of total NaDF within 3h at pH 7 but little-to-no drug release at pH 4.5. NaDF permeation across the prepared membranes demonstrated a reversible pH-responsiveness. The pH-responsive polyurethane membranes did not show any noticeable negative impact on vaginal epithelial cell viability or induction of pro-inflammatory cytokine production compared to controls. Overall, the non-cytotoxic HEP-based pH-responsive polyurethane demonstrated its potential to be used in membrane-based implants such as intravaginal rings to achieve on-demand "on-and-off" intravaginal drug delivery. A reversible and sharp switch between "off" and "on" drug release is achieved for the first time through new pH-sensitive polyurethane membranes, which can serve as window membranes in reservoir-type intravaginal rings for on-demand drug delivery to prevent sexually transmitted infections (STIs). Close to zero drug release occurs at the normal vaginal pH (4.5) for minimal side effects. Drug release is only triggered by elevation of pH to 7 during heterosexual intercourse. The reversibly sharp and fast "on-and-off" switch arises from the creative incorporation of a pH-sensitive monomer in the soft segment of polyurethane. This polyurethane biomaterial holds great potential to better protect women who are generally at higher risk and are more vulnerable to STIs. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Sexual Dimorphism and Allometric Effects Associated With the Wing Shape of Seven Moth Species of Sphingidae (Lepidoptera: Bombycoidea).

PubMed

de Camargo, Willian Rogers Ferreira; de Camargo, Nícholas Ferreira; Corrêa, Danilo do Carmo Vieira; de Camargo, Amabílio J Aires; Diniz, Ivone Rezende

2015-01-01

Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females). © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Fire Protection Materials

NASA Technical Reports Server (NTRS)

1980-01-01

Avco has drawn upon its heat shield experience to develop a number of widely-accepted commercial fire protection materials. Originating from NASA's space shuttle thermal protection system, one such material is Chartek 59 fireproofing, an intumescent epoxy coating specifically designed for outdoor use by industrial facilities dealing with highly flammable products such as oil refineries and chemical plants. The coating is applied usually by spray gun to exterior structural steel conduits, pipes and valves, offshore platforms and liquefied petroleum gas tanks. Fireproofing provides two types of protection: ablation or dissipation of heat by burn-off and "intumescence" or swelling; the coating swells to about five times its original size, forming a protective blanket of char which retards transfer of heat to the metal structure preventing loss of structural strength and possible collapse which would compound the fire fighting problem.

Modulation of monocytic leukemia cell function and survival by high gradient magnetic fields and mathematical modeling studies.

PubMed

Zablotskii, Vitalii; Syrovets, Tatiana; Schmidt, Zoe W; Dejneka, Alexandr; Simmet, Thomas

2014-03-01

The influence of spatially modulated high gradient magnetic fields on cellular functions of human THP-1 leukemia cells is studied. We demonstrate that arrays of high-gradient micrometer-sized magnets induce i) cell swelling, ii) prolonged increased ROS production, and iii) inhibit cell proliferation, and iv) elicit apoptosis of THP-1 monocytic leukemia cells in the absence of chemical or biological agents. Mathematical modeling indicates that mechanical stress exerted on the cells by high magnetic gradient forces is responsible for triggering cell swelling and formation of reactive oxygen species followed by apoptosis. We discuss physical aspects of controlling cell functions by focused magnetic gradient forces, i.e. by a noninvasive and nondestructive physical approach. Copyright © 2014 Elsevier Ltd. All rights reserved.

The mating brain: early maturing sneaker males maintain investment into the brain also under fast body growth in Atlantic salmon (Salmo salar).

PubMed

Kotrschal, Alexander; Trombley, Susanne; Rogell, Björn; Brannström, Ioana; Foconi, Eric; Schmitz, Monika; Kolm, Niclas

It has been suggested that mating behaviours require high levels of cognitive ability. However, since investment into mating and the brain both are costly features, their relationship is likely characterized by energetic trade-offs. Empirical data on the subject remains equivocal. We investigated if early sexual maturation was associated with brain development in Atlantic salmon ( Salmo salar ), in which males can either stay in the river and sexually mature at a small size (sneaker males) or migrate to the sea and delay sexual maturation until they have grown much larger (anadromous males). Specifically, we tested how sexual maturation may induce plastic changes in brain development by rearing juveniles on either natural or ad libitum feeding levels. After their first season we compared brain size and brain region volumes across both types of male mating tactics and females. Body growth increased greatly across both male mating tactics and females during ad libitum feeding as compared to natural feeding levels. However, despite similar relative increases in body size, early maturing sneaker males maintained larger relative brain size during ad libitum feeding levels as compared to anadromous males and females. We also detected several differences in the relative size of separate brain regions across feeding treatments, sexes and mating strategies. For instance, the relative size of the cognitive centre of the brain, the telencephalon, was largest in sneaker males. Our data support that a large relative brain size is maintained in individuals that start reproduction early also during fast body growth. We propose that the cognitive demands during complex mating behaviours maintain a high level of investment into brain development in reproducing individuals.

Civic Learning and Teaching as a Resource for Sexual Justice: An Undergraduate Religious Studies Course Module

ERIC Educational Resources Information Center

Vasko, Elisabeth T.

2017-01-01

Civic learning and teaching, a form of critical and democratically engaged pedagogy, is utilized in an upper-level undergraduate sexual ethics course to leverage public problem solving around the sexual violence on a mid-size Catholic collegiate campus. Through the course, students, faculty, staff, and community members work together to deepen…

Application of pinch-and-swell structure rheology gauge to determine rock paleo-rheological parameters in Taili, western Liaoning, NE China

NASA Astrophysics Data System (ADS)

Sun, Zhengquan; Zeng, Zuoxun; Wu, Linbo; Xu, Shaopeng; Yang, Shuang; Chen, Deli; Wang, Jianxiu

2017-05-01

New results, in combination with previously published ones, reveal that when the Stress Exponent of the Competent layer (SEC) ranges from 1 to 10 (1 < n < 10), Pinch-and-Swell structure Rheology Gauge (PSRG) can only be available under the condition that the Viscosity ratio between the Competent layer and its corresponding Matrix layer (VCM) is larger than 10. Therefore, we made the attempt to calculate the viscosity ratio of pinch-and-swell structure of competent layer to the related matrix and stress exponent. Based on this knowledge, we applied this gauge to calculate SECs and VCMs of eight types of pinch-and-swell structures, which are widely developed in the Taili area of the west Liaoning Province in China. Statistical analysis of the SEC resulted in intervals of four types of competent layers, that is, Medium-scale Granitic coarse-to-pegmatitic Veins, Small-scale Augen Granite aplite Veins, Small-scale Granite aplite Veins, and Small-scale Augen Quartz-K-feldspar veins, with intervals of [3.50, 4.63], [2.64, 4.29], [2.70, 3.51], and [2.50, 3.36] respectively. The preferred intervals of VCM of the five types of pinch-and-swell structures, Small-scale Augen Granite aplite Veins + Fine-grained Biotite-Hornblende-plagioclase Gneiss, Medium-scale Granitic coarse-to-pegmatitic Veins + Fine-grained Biotite-Hornblende-plagioclase Gneiss, Small-scale Augen Granite aplite Veins + medium-to-fine-grained granitic gneiss, Medium-scale Granitic coarse-to-pegmatitic Veins + medium-to-fine-grained granitic gneiss, and Small-scale Augen Granite aplite Veins + fine-grained biotite-plagioclase gneiss, are [19.98, 62.51], [15.90, 61.17], [26.72, 93.27], [22.21, 107.26], and [76.33, 309.39] respectively. The similarities between these calculated SEC statistical preferred intervals and the physical experimental results verify the validity of the PSRG. The competent layers of the pinch-and-swell structures were presented in this study as power-law flow with SEC values that increased with the thickness of the layer. Grain-size plays an important role in the rheology of pinch-and-swell structures. The results offer a case for the application of PSRG and determine the key rock rheological parameters of North China Craton for future related studies.

Paradoxes of thermodynamics of swelling equilibria of polymers in liquids and vapors.

PubMed

Davankov, Vadim A; Pastukhov, Alexander V

2011-12-29

An automatic registration of the changing size of a single spherical microbead of a cross-linked polymer was applied for studying the swelling process of the bead by the sorption of vapors and/or liquids. Many representatives of all three basic types of polymeric networks, gel-type, hypercrosslinked, and macroporous, were examined. Only the first two display large volume changes and prove suitable for following the kinetics and extent of swelling by the above dilatometric technique. The results unambiguously prove that swelling of all polymeric networks in liquids is always higher than in corresponding saturated vapors (Schroeder's paradox). The general nature of this phenomenon implies that the absolute activity of any sorbate in its liquid form is always larger than in the form of its saturated vapor. Surprisingly, gels with any solvent contents, which fall into the broad range between the vapor-equilibrated and liquid-equilibrated extreme contents, retain their volumes constant in the saturated vapor atmosphere. This paradox of a wide range of gels swollen to a different extent and, nevertheless, standing in equilibrium with saturated vapor is explained by the specificity of the network polymers, namely, that the energy of the solvent-polymer interactions is easily compensated by the energy of remaining between-chain interactions at any solvent content in the above range. Therefore, the strain-free swollen gels do not generate enhanced vapor pressure, but neither display the ability to take up more sorbate from its vapor. © 2011 American Chemical Society

Decoupling of mass transport mechanisms in the stagewise swelling of multiple emulsions.

PubMed

Bahtz, Jana; Gunes, Deniz Z; Hughes, Eric; Pokorny, Lea; Riesch, Francesca; Syrbe, Axel; Fischer, Peter; Windhab, Erich J

2015-05-19

This contribution reports on the mass transport kinetics of osmotically imbalanced water-in-oil-in-water (W1/O/W2) emulsions. Although frequently studied, the control of mass transport in W1/O/W2 emulsions is still challenging. We describe a microfluidics-based method to systematically investigate the impact of various parameters, such as osmotic pressure gradient, oil phase viscosity, and temperature, on the mass transport. Combined with optical microscopy analyses, we are able to identify and decouple the various mechanisms, which control the dynamic droplet size of osmotically imbalanced W1/O/W2 emulsions. So, swelling kinetics curves with a very high accuracy are generated, giving a basis for quantifying the kinetic aspects of transport. Two sequential swelling stages, i.e., a lag stage and an osmotically dominated stage, with different mass transport mechanisms are identified. The determination and interpretation of the different stages are the prerequisite to control and trigger the swelling process. We show evidence that both mass transport mechanisms can be decoupled from each other. Rapid osmotically driven mass transport only takes place in a second stage induced by structural changes of the oil phase in a lag stage, which allow an osmotic exchange between both water phases. Such structural changes are strongly facilitated by spontaneous water-in-oil emulsification. The duration of the lag stage is pressure-independent but significantly influenced by the oil phase viscosity and temperature.

Identification of Multiple QTLs Linked to Neuropathology in the Engrailed-1 Heterozygous Mouse Model of Parkinson's Disease.

PubMed

Kurowska, Zuzanna; Jewett, Michael; Brattås, Per Ludvik; Jimenez-Ferrer, Itzia; Kenéz, Xuyian; Björklund, Tomas; Nordström, Ulrika; Brundin, Patrik; Swanberg, Maria

2016-08-23

Motor symptoms in Parkinson's disease are attributed to degeneration of midbrain dopaminergic neurons (DNs). Heterozygosity for Engrailed-1 (En1), one of the key factors for programming and maintenance of DNs, results in a parkinsonian phenotype featuring progressive degeneration of DNs in substantia nigra pars compacta (SNpc), decreased striatal dopamine levels and swellings of nigro-striatal axons in the SwissOF1-En1+/- mouse strain. In contrast, C57Bl/6-En1+/- mice do not display this neurodegenerative phenotype, suggesting that susceptibility to En1 heterozygosity is genetically regulated. Our goal was to identify quantitative trait loci (QTLs) that regulate the susceptibility to PD-like neurodegenerative changes in response to loss of one En1 allele. We intercrossed SwissOF1-En1+/- and C57Bl/6 mice to obtain F2 mice with mixed genomes and analyzed number of DNs in SNpc and striatal axonal swellings in 120 F2-En1+/- 17 week-old male mice. Linkage analyses revealed 8 QTLs linked to number of DNs (p = 2.4e-09, variance explained = 74%), 7 QTLs linked to load of axonal swellings (p = 1.7e-12, variance explained = 80%) and 8 QTLs linked to size of axonal swellings (p = 7.0e-11, variance explained = 74%). These loci should be of prime interest for studies of susceptibility to Parkinson's disease-like damage in rodent disease models and considered in clinical association studies in PD.

Internal jugular vein aneurysm: A case report.

PubMed

Nasiri, Abdulrahman M; Rayes, Nora; Bakarman, Khaled A

2018-01-01

Aneurysm is a localized dilatation of an artery of at least 1.5 times the normal diameter that occurs when part of an artery wall weakens or is injured, allowing it to widen abnormally. In practice, an arterial aneurysm is more common in comparison to a venous aneurysm. Because of the rare incidence of venous aneurysms, treatment guidelines are not clearly established and thus treatment strategies vary. This is a case of a 57-year-old Saudi woman, with no significant medical history, who presented to Prince Sultan Military Hospital complaining of swelling in the right side of the neck that started 3 years ago. The patient reported that the swelling enlarged with coughing and straining, but there was no pain, change in skin color, dysphagia, change in voice, neurological defect, shortness of breath, history of any trauma to the neck, surgical intervention, or any lump. The condition can be diagnosed via ultrasonography, computed tomography, or magnetic resonance imaging. Despite the lack of guidelines, intervention was necessary because the patient was anxious regarding the increase in the size of the swelling, which she felt had a negative psychosocial impact. Moreover, because the sizable venous aneurysm harbored a mural thrombus that increased the risk of embolization and pulmonary embolism, surgery was offered.Indication for surgery includes pain, swelling, and cosmetic concerns. Conservative management of the condition is described in the literature. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Some radiation effects on organic binders in X-ray fluorescence spectrometry

NASA Astrophysics Data System (ADS)

Novosel-Radović, Vj.; MaljkoviĆ, Da.; NenadiĆ, N.

The paper deals with diminished wear resistance of standard samples in X-ray fluorescence spectrometry. The effect of X-ray irradiation on pellet samples, pressed with starch as organic binder, was investigated by sieve analysis and scanning electron microscopy. A change in the starch grain size was found as a result of swelling and cracking.

Impact of petroleum products on soil composition and physical-chemical properties

NASA Astrophysics Data System (ADS)

Brakorenko, N. N.; Korotchenko, T. V.

2016-03-01

The article describes the grain-size distribution, physical and mechanical properties, swelling and specific electrical resistivity of soils before and after the contact with petroleum products. The changes in mechanical properties of soils contaminated with petroleum products have been stated. It leads to the increase in compressibility values, decline in internal friction angle and cohesion.

Demographic monitoring of Wright fishhook cactus

Treesearch

Ronald J. Kass

2001-01-01

Wright fishhook cactus (Sclerocactus wrightiae Benson) is a small barrel cactus endemic to the San Rafael Swell in south-central Utah. It was listed as an endangered species in 1979 due to its small population size, threats of over-collecting, and development associated with oil and gas. Demographic monitoring was initiated in 1993 with the following objectives: to...

The evolution of genital complexity and mating rates in sexually size dimorphic spiders.

PubMed

Kuntner, Matjaž; Cheng, Ren-Chung; Kralj-Fišer, Simona; Liao, Chen-Pan; Schneider, Jutta M; Elgar, Mark A

2016-11-09

Genital diversity may arise through sexual conflict over polyandry, where male genital features function to manipulate female mating frequency against her interest. Correlated genital evolution across animal groups is consistent with this view, but a link between genital complexity and mating rates remains to be established. In sexually size dimorphic spiders, golden orbweaving spiders (Nephilidae) males mutilate their genitals to form genital plugs, but these plugs do not always prevent female polyandry. In a comparative framework, we test whether male and female genital complexity coevolve, and how these morphologies, as well as sexual cannibalism, relate to the evolution of mating systems. Using a combination of comparative tests, we show that male genital complexity negatively correlates with female mating rates, and that levels of sexual cannibalism negatively correlate with male mating rates. We also confirm a positive correlation between male and female genital complexity. The macroevolutionary trajectory is consistent with a repeated evolution from polyandry to monandry coinciding with the evolution towards more complex male genitals. These results are consistent with the predictions from sexual conflict theory, although sexual conflict may not be the only mechanism responsible for the evolution of genital complexity and mating systems. Nevertheless, our comparative evidence suggests that in golden orbweavers, male genital complexity limits female mating rates, and sexual cannibalism by females coincides with monogyny.

The use of magnetic resonance imaging for studying female sexual function: A review.

PubMed

Vaccaro, Christine M

2015-04-01

Many would agree that there are two quintessential sexual organs in the female: the clitoris and the brain. Using non-invasive techniques of magnetic resonance imaging (MRI), investigators have gained insight into the mental and physical factors involved in female sexual function. Since only the external clitoral glans is easily accessible for direct measurement, the complete anatomy of the clitoris (including the internal components-paired corpora, crura, and bulbs) has only recently been described, with MRI providing the most sensitive way of distinguishing among the various soft tissue planes. Average sizes of clitoral structures and average distances between the clitoral complex and other pelvic landmarks have been measured. These measurements have been correlated with female sexual function: a longer distance between the clitoral complex and the vaginal lumen correlates with poorer sexual function, consistent with prior imaging studies. However, whether clitoral size influences function is debatable, so further studies are needed. Physiological investigations have demonstrated that female arousal disorder is unlikely to be due to inadequate genital engorgement. Some consider the brain to be the ultimate sexual organ, and several recent studies have used functional MRI (fMRI) to reveal sexual excitability in the brain. The normal sexual response requires deactivation of the frontal lobe and activation of the instinctual limbic system of the midbrain. As MR technology continues to improve, the mysteries of female sexuality will be further unraveled. © 2015 Wiley Periodicals, Inc.

Structural characteristics of the online social networks of maltreated youth and offline sexual risk behavior.

PubMed

Negriff, Sonya; Valente, Thomas W

2018-02-07

Maltreated youth are at risk for exposure to online sexual content and high-risk sexual behavior, yet characteristics of their online social networks have not been examined as a potential source of vulnerability. The aims of the current study were: 1) to test indicators of size (number of friends) and fragmentation (number of connections between friends) of maltreated young adults' online networks as predictors of intentional and unintentional exposure to sexual content and offline high-risk sexual behavior and 2) to test maltreatment as a moderator of these associations. Participants were selected from a longitudinal study on the effects of child maltreatment (n = 152; Mean age 21.84 years). Data downloaded from Facebook were used to calculate network variables of size (number of friends), density (connections between friends), average degree (average number of connections for each friend), and percent isolates (those not connected to others in the network). Self-reports of intentional and unintentional exposure to online sexual content and offline high-risk sexual behavior were the outcome variables. Multiple-group path modeling showed that only for the maltreated group having a higher percent of isolates in the network predicted intentional exposure to online sexual content and offline high-risk sexual behavior. An implication of this finding is that the composition of the Facebook network may be used as a risk indicator for individuals with child-welfare documented maltreatment experiences. Copyright © 2018. Published by Elsevier Ltd.

Female Sexual Victimization Among College Students: Assault Severity, Health Risk Behaviors, and Sexual Functioning.

PubMed

Turchik, Jessica A; Hassija, Christina M

2014-09-01

The purpose of the present study was to examine the relationship between college women's sexual victimization experiences, health risk behaviors, and sexual functioning. A sample of 309 college women at a mid-sized Midwestern university completed measures assessing sexual victimization, sexual risk taking, substance use behaviors, sexual desire, sexual functioning, prior sexual experiences, and social desirability. Severity of sexual victimization was measured using a multi-item, behaviorally specific, gender-neutral measure, which was divided into four categories based on severity (none, sexual contact, sexual coercion, rape). Within the sample, 72.8% (n = 225) of women reported at least one experience of sexual victimization since age 16. Results from MANCOVAs and a multinomial logistic regression, controlling for social desirability and prior sexual experience, revealed that sexual victimization among female students was related to increased drug use, problematic drinking behaviors, sexual risk taking, sexual dysfunction, and dyadic sexual desire. In addition, findings indicated that women exposed to more severe forms of sexual victimization (i.e., rape) were most likely to report these risk-taking behaviors and sexual functioning issues. Implications for sexual assault risk reduction programming and treatment are discussed. © The Author(s) 2014.

Comparing two books and establishing probably efficacious treatment for low sexual desire.

PubMed

Balzer, Alexandra M; Mintz, Laurie B

2015-04-01

Using a sample of 45 women, this study compared the effectiveness of a previously studied (Mintz, Balzer, Zhao, & Bush, 2012) bibliotherapy intervention (Mintz, 2009), a similar self-help book (Hall, 2004), and a wait-list control (WLC) group. To examine intervention effectiveness, between and within group standardized effect sizes (interpreted with Cohen's, 1988 benchmarks .20 = small, .50 = medium, .80+ = large) and their confidence limits are used. In comparison to the WLC group, both interventions yielded large between-group posttest effect sizes on a measure of sexual desire. Additionally, large between-group posttest effect sizes were found for sexual satisfaction and lubrication among those reading the Mintz book. When examining within-group pretest to posttest effect sizes, medium to large effects were found for desire, lubrication, and orgasm for both books and for satisfaction and arousal for those reading the Mintz book. When directly comparing the books, all between-group posttest effect sizes were likely obtained by chance. It is concluded that both books are equally effective in terms of the outcome of desire, but whether or not there is differential efficacy in terms of other domains of sexual functioning is equivocal. Tentative evidence is provided for the longer term effectiveness of both books in enhancing desire. Arguing for applying criteria for empirically supported treatments to self-help, results are purported to establish the Mintz book as probably efficacious and to comprise a first step in this designation for the Hall book. (c) 2015 APA, all rights reserved).

Evolution of sexual dimorphism in bill size and shape of hermit hummingbirds (Phaethornithinae): a role for ecological causation

PubMed Central

Temeles, Ethan J.; Miller, Jill S.; Rifkin, Joanna L.

2010-01-01

Unambiguous examples of ecological causation of sexual dimorphism are rare, and the best evidence involves sexual differences in trophic morphology. We show that moderate female-biased sexual dimorphism in bill curvature is the ancestral condition in hermit hummingbirds (Phaethornithinae), and that it is greatly amplified in species such as Glaucis hirsutus and Phaethornis guy, where bills of females are 60 per cent more curved than bills of males. In contrast, bill curvature dimorphism is lost or reduced in a lineage of short-billed hermit species and in specialist Eutoxeres sicklebill hermits. In the hermits, males tend to be larger than females in the majority of species, although size dimorphism is typically small. Consistent with earlier studies of hummingbird feeding performance, both raw regressions of traits and phylogenetic independent contrasts supported the prediction that dimorphism in bill curvature of hermits is associated with longer bills. Some evidence indicates that differences between sexes of hermit hummingbirds are associated with differences in the use of food plants. We suggest that some hermit hummingbirds provide model organisms for studies of ecological causation of sexual dimorphism because their sexual dimorphism in bill curvature provides a diagnostic clue for the food plants that need to be monitored for studies of sexual differences in resource use. PMID:20194168

Coevolution of female and male genital components to avoid genital size mismatches in sexually dimorphic spiders.

PubMed

Lupše, Nik; Cheng, Ren-Chung; Kuntner, Matjaž

2016-08-17

In most animal groups, it is unclear how body size variation relates to genital size differences between the sexes. While most morphological features tend to scale with total somatic size, this does not necessarily hold for genitalia because divergent evolution in somatic size between the sexes would cause genital size mismatches. Theory predicts that the interplay of female-biased sexual size dimorphism (SSD) and sexual genital size dimorphism (SGD) should adhere to the 'positive genital divergence', the 'constant genital divergence', or the 'negative genital divergence' model, but these models remain largely untested. We test their validity in the spider family Nephilidae known for the highest degrees of SSD among terrestrial animals. Through comparative analyses of sex-specific somatic and genital sizes, we first demonstrate that 99 of the 351 pairs of traits are phylogenetically correlated. Through factor analyses we then group these traits for MCMCglmm analyses that test broader correlation patterns, and these reveal significant correlations in 10 out of the 36 pairwise comparisons. Both types of analyses agree that female somatic and internal genital sizes evolve independently. While sizes of non-intromittent male genital parts coevolve with male body size, the size of the intromittent male genital parts is independent of the male somatic size. Instead, male intromittent genital size coevolves with female (external and, in part, internal) genital size. All analyses also agree that SGD and SSD evolve independently. Internal dimensions of female genitalia evolve independently of female body size in nephilid spiders, and similarly, male intromittent genital size evolves independently of the male body size. The size of the male intromittent organ (the embolus) and the sizes of female internal and external genital components thus seem to respond to selection against genital size mismatches. In accord with these interpretations, we reject the validity of the existing theoretical models of genital and somatic size dimorphism in spiders.

Concurrent natural and sexual selection in wild male sockeye salmon, Oncorhynchus nerka.

PubMed

Hamon, Troy R; Foote, Chris J

2005-05-01

Concurrent natural and sexual selection have been inferred from laboratory and comparative studies in a number of taxa, but are rarely measured in natural populations. Because the interaction of these two general categories of selection may be complex when they occur simultaneously, empirical evidence from natural populations would help us to understand this interaction and probably give us greater insight into each separate episode as well. In male sockeye salmon, sexual selection for larger body size has been indicated in both deep and shallow water habitats. However, in shallow habitats male sockeye are generally smaller and less deep-bodied than in deep habitats, a difference that has been ascribed to natural selection. We measured concurrent natural and sexual selection in two years on breeding male sockeye salmon with respect to body size, body shape, and time of arrival to the breeding grounds. Natural selection was variable in effect and sexual selection was variable in intensity in these two years. The patterns of selection also appear to be interdependent; areas where predation on spawning adults is not intense have yielded different patterns of sexual selection than those measured here. It appears that some of the body shape differences in sockeye salmon associated with different spawning habitats, which were previously attributed to selective mortality, may be a result of different patterns of sexual selection in the different habitats. Total selection resulting from the combination of both natural and sexual selection was less intense than either natural or sexual selection in most cases. Measurement of concurrent selection episodes in nature may help us to understand whether the pattern of differential sexual selection is common, and whether observed patterns of habitat-related differentiation may be due to differences in sexual selection.

A novel method of comparing mating success and survival reveals similar sexual and viability selection for mobility traits in female tree crickets.

PubMed

Ercit, K; Gwynne, D T

2016-06-01

The relationship between sexual and viability selection in females is necessarily different than that in males, as investment in sexual traits potentially comes at the expense of both fecundity and survival. Accordingly, females do not usually invest in sexually selected traits. However, direct benefits obtained from mating, such as nuptial gifts, may encourage competition among females and subsidize investment into sexually selected traits. We compared sexual and viability selection on female tree crickets Oecanthus nigricornis, a species where females mate frequently to obtain nuptial gifts and sexual selection on females is likely. If male choice determines female mating success in this species, we expect sexual selection for fecundity traits, as males of many species prefer more fecund females. Alternatively, intrasexual scramble or combat competition on females may select for larger jumping legs or wider heads (respectively). We estimated mating success in wild caught crickets using microsatellite analysis of stored sperm and estimated relative viability by comparing surviving female O. nigricornis to those captured by a common wasp predator. In support of the scramble competition hypothesis, we found sexual selection for females with larger hind legs and narrower heads. We also found stabilizing viability selection for intermediate head width and hind leg size. As predicted, traits under viability and sexual selection were very similar, and the direction of that selection was not opposing. However, because the shape of sexual and viability selection differs, these episodes of selection may favour slightly different trait sizes. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

DOE Office of Scientific and Technical Information (OSTI.GOV)

El-Atwani, Osman; Nathaniel II, James E.; Leff, Asher C.

Nanocrystalline materials are radiation-tolerant materials’ candidates due to their high defect sink density. Here, nanocrystalline iron films were irradiated with 10 keV helium ions in situ in a transmission electron microscope at elevated temperatures. Grain-size-dependent bubble density changes and denuded zone occurrence were observed at 700 K, but not at 573 K. This transition, attributed to increased helium–vacancy migration at elevated temperatures, suggests that nanocrystalline microstructures are more resistant to swelling at 700 K due to decreased bubble density. Finally, denuded zone formation had no correlation with grain size and misorientation angle under the conditions studied.

Size-assortative mating and effect of maternal body size on the reproductive output of the nassariid Buccinanops globulosus

NASA Astrophysics Data System (ADS)

Avaca, María Soledad; Narvarte, Maite; Martín, Pablo

2012-04-01

Size- assortative mating is usually present in populations where there is a positive relationship between female size and reproductive output. In this study, we tested for the presence of sexual size dimorphism, size-assortative mating and the effects of female size on reproductive output in a wild population of Buccinanops globulosus, an endemic nassariid of the Southwestern Atlantic Ocean with direct development. The results showed that: 1) females were larger than males, indicating sexual size dimorphism; 2) mate sizes were significantly correlated, indicating a component of size-assortative mating; 3) males of medium and large size classes were paired with larger females than small-sized males; 4) larger females were paired with large males; 5) maternal body size was positively related to some proxies of reproductive success (number of nurse eggs per egg capsule, egg capsular area and total length at hatching). Our results suggest that larger females may be favored as mates over smaller ones owing to their higher investment per offspring and consequently a larger initial juvenile size as juvenile.

Swelling of biological and semiflexible polyelectrolytes.

PubMed

Dobrynin, Andrey V; Carrillo, Jan-Michael Y

2009-10-21

We have developed a theoretical model of swelling of semiflexible (biological) polyelectrolytes in salt solutions. Our approach is based on separation of length scales which allowed us to split a chain's electrostatic energy into two parts that describe local and remote electrostatic interactions along the polymer backbone. The local part takes into account interactions between charged monomers that are separated by distances along the polymer backbone shorter than the chain's persistence length. These electrostatic interactions renormalize chain persistence length. The second part includes electrostatic interactions between remote charged pairs along the polymer backbone located at distances larger than the chain persistence length. These interactions are responsible for chain swelling. In the framework of this approach we calculated effective chain persistence length and chain size as a function of the Debye screening length, chain degree of ionization, bare persistence length and chain degree of polymerization. Our crossover expression for the effective chain's persistence length is in good quantitative agreement with the experimental data on DNA. We have been able to fit experimental datasets by using two adjustable parameters: DNA ionization degree (α = 0.15-0.17) and a bare persistence length (l(p) = 40-44 nm).

Development of visible-light responsive and mechanically enhanced "smart" UCST interpenetrating network hydrogels.

PubMed

Xu, Yifei; Ghag, Onkar; Reimann, Morgan; Sitterle, Philip; Chatterjee, Prithwish; Nofen, Elizabeth; Yu, Hongyu; Jiang, Hanqing; Dai, Lenore L

2017-12-20

An interpenetrating polymer network (IPN), chlorophyllin-incorporated environmentally responsive hydrogel was synthesized and exhibited the following features: enhanced mechanical properties, upper critical solution temperature (UCST) swelling behavior, and promising visible-light responsiveness. Poor mechanical properties are known challenges for hydrogel-based materials. By forming an interpenetrating network between polyacrylamide (PAAm) and poly(acrylic acid) (PAAc) polymer networks, the mechanical properties of the synthesized IPN hydrogels were significantly improved compared to hydrogels made of a single network of each polymer. The formation of the interpenetrating network was confirmed by Fourier Transform Infrared Spectroscopy (FTIR), the analysis of glass transition temperature, and a unique UCST responsive swelling behavior, which is in contrast to the more prevalent lower critical solution temperature (LCST) behaviour of environmentally responsive hydrogels. The visible-light responsiveness of the synthesized hydrogel also demonstrated a positive swelling behavior, and the effect of incorporating chlorophyllin as the chromophore unit was observed to reduce the average pore size and further enhance the mechanical properties of the hydrogel. This interpenetrating network system shows potential to serve as a new route in developing "smart" hydrogels using visible-light as a simple, inexpensive, and remotely controllable stimulus.

Superior radiation-resistant nanoengineered austenitic 304L stainless steel for applications in extreme radiation environments

NASA Astrophysics Data System (ADS)

Sun, C.; Zheng, S.; Wei, C. C.; Wu, Y.; Shao, L.; Yang, Y.; Hartwig, K. T.; Maloy, S. A.; Zinkle, S. J.; Allen, T. R.; Wang, H.; Zhang, X.

2015-01-01

Nuclear energy provides more than 10% of electrical power internationally, and the increasing engagement of nuclear energy is essential to meet the rapid worldwide increase in energy demand. A paramount challenge in the development of advanced nuclear reactors is the discovery of advanced structural materials that can endure extreme environments, such as severe neutron irradiation damage at high temperatures. It has been known for decades that high dose radiation can introduce significant void swelling accompanied by precipitation in austenitic stainless steel (SS). Here we report, however, that through nanoengineering, ultra-fine grained (UFG) 304L SS with an average grain size of ~100 nm, can withstand Fe ion irradiation at 500°C to 80 displacements-per-atom (dpa) with moderate grain coarsening. Compared to coarse grained (CG) counterparts, swelling resistance of UFG SS is improved by nearly an order of magnitude and swelling rate is reduced by a factor of 5. M23C6 precipitates, abundant in irradiated CG SS, are largely absent in UFG SS. This study provides a nanoengineering approach to design and discover radiation tolerant metallic materials for applications in extreme radiation environments.

Superior radiation-resistant nanoengineered austenitic 304L stainless steel for applications in extreme radiation environments

DOE PAGES

Sun, C.; Zheng, S.; Wei, C. C.; ...

2015-01-15

Nuclear energy provides more than 10% of electrical power internationally, and the increasing engagement of nuclear energy is essential to meet the rapid worldwide increase in energy demand. A paramount challenge in the development of advanced nuclear reactors is the discovery of advanced structural materials that can endure extreme environments, such as severe neutron irradiation damage at high temperatures. It has been known for decades that high dose radiation can introduce significant void swelling accompanied by precipitation in austenitic stainless steel (SS). Here we report, however, that through nanoengineering, ultra-fine grained (UFG) 304L SS with an average grain size ofmore » ~100 nm, can withstand Fe ion irradiation at 500°C to 80 displacements-per-atom (dpa) with moderate grain coarsening. Compared to coarse grained (CG) counterparts, swelling resistance of UFG SS is improved by nearly an order of magnitude and swelling rate is reduced by a factor of 5. M₂₃C₆ precipitates, abundant in irradiated CG SS, are largely absent in UFG SS. This study provides a nanoengineering approach to design and discover radiation tolerant metallic materials for applications in extreme radiation environments.« less

Superior radiation-resistant nanoengineered austenitic 304L stainless steel for applications in extreme radiation environments.

PubMed

Sun, C; Zheng, S; Wei, C C; Wu, Y; Shao, L; Yang, Y; Hartwig, K T; Maloy, S A; Zinkle, S J; Allen, T R; Wang, H; Zhang, X

2015-01-15

Nuclear energy provides more than 10% of electrical power internationally, and the increasing engagement of nuclear energy is essential to meet the rapid worldwide increase in energy demand. A paramount challenge in the development of advanced nuclear reactors is the discovery of advanced structural materials that can endure extreme environments, such as severe neutron irradiation damage at high temperatures. It has been known for decades that high dose radiation can introduce significant void swelling accompanied by precipitation in austenitic stainless steel (SS). Here we report, however, that through nanoengineering, ultra-fine grained (UFG) 304 L SS with an average grain size of ~100 nm, can withstand Fe ion irradiation at 500 °C to 80 displacements-per-atom (dpa) with moderate grain coarsening. Compared to coarse grained (CG) counterparts, swelling resistance of UFG SS is improved by nearly an order of magnitude and swelling rate is reduced by a factor of 5. M(23)C(6) precipitates, abundant in irradiated CG SS, are largely absent in UFG SS. This study provides a nanoengineering approach to design and discover radiation tolerant metallic materials for applications in extreme radiation environments.

Superior radiation-resistant nanoengineered austenitic 304L stainless steel for applications in extreme radiation environments

PubMed Central

Sun, C.; Zheng, S.; Wei, C. C.; Wu, Y.; Shao, L.; Yang, Y.; Hartwig, K. T.; Maloy, S. A.; Zinkle, S. J.; Allen, T. R.; Wang, H.; Zhang, X.

2015-01-01

Nuclear energy provides more than 10% of electrical power internationally, and the increasing engagement of nuclear energy is essential to meet the rapid worldwide increase in energy demand. A paramount challenge in the development of advanced nuclear reactors is the discovery of advanced structural materials that can endure extreme environments, such as severe neutron irradiation damage at high temperatures. It has been known for decades that high dose radiation can introduce significant void swelling accompanied by precipitation in austenitic stainless steel (SS). Here we report, however, that through nanoengineering, ultra-fine grained (UFG) 304L SS with an average grain size of ~100 nm, can withstand Fe ion irradiation at 500°C to 80 displacements-per-atom (dpa) with moderate grain coarsening. Compared to coarse grained (CG) counterparts, swelling resistance of UFG SS is improved by nearly an order of magnitude and swelling rate is reduced by a factor of 5. M23C6 precipitates, abundant in irradiated CG SS, are largely absent in UFG SS. This study provides a nanoengineering approach to design and discover radiation tolerant metallic materials for applications in extreme radiation environments. PMID:25588326

A meta-analysis of the relations between three types of peer norms and adolescent sexual behavior

PubMed Central

van de Bongardt, Daphne; Reitz, Ellen; Sandfort, Theo; Deković, Maja

2018-01-01

The aim of the present meta-analysis was to investigate the associations between three types of peer norms–descriptive norms (peer sexual behaviors), injunctive norms (peer sexual attitudes), and peer pressure to have sex–and two adolescent sexual behavior outcomes (sexual activity and sexual risk behavior). Adolescent sexual activity was more strongly associated with descriptive norms (ESrfixed = .40) than with injunctive norms (ESrfixed = .22) or peer pressure (ESrfixed = .10). Compared with the sexual activity outcome, the effect size for descriptive norms (peer sexual risk behavior) for sexual risk behavior was smaller (ESrfixed = .11). Age, gender, peer type, and socio-cultural context significantly moderated these associations. Additional analyses of longitudinal studies suggested that selection effects were stronger than socialization effects. These findings offer empirical support for the conceptual distinction between three types of peer norms and hold important implications for theory, research, and intervention strategies. PMID:25217363

Sexual minorities and selection of a primary care physician in a midwestern U.S. city.

PubMed

Labig, Chalmer E; Peterson, Tim O

2006-01-01

How and why sexual minorities select a primary care physician is critical to the development of methods for attracting these clients to a physician's practice. Data obtained from a sample of sexual minorities in a mid-size city in our nation's heartland would indicate that these patients are loyal when the primary care physician has a positive attitude toward their sexual orientation. The data also confirms that most sexual minorities select same sex physicians but not necessarily same sexual orientation physicians because of lack of knowledge of physicians' sexual orientation. Family practice physicians and other primary care physicians can reach out to this population by encouraging word of mouth advertising and by displaying literature on health issues for all sexual orientations in their offices.

Sexual Networks and HIV Risk among Black Men Who Have Sex with Men in 6 U.S. Cities.

PubMed

Tieu, Hong-Van; Liu, Ting-Yuan; Hussen, Sophia; Connor, Matthew; Wang, Lei; Buchbinder, Susan; Wilton, Leo; Gorbach, Pamina; Mayer, Kenneth; Griffith, Sam; Kelly, Corey; Elharrar, Vanessa; Phillips, Gregory; Cummings, Vanessa; Koblin, Beryl; Latkin, Carl

2015-01-01

Sexual networks may place U.S. Black men who have sex with men (MSM) at increased HIV risk. Self-reported egocentric sexual network data from the prior six months were collected from 1,349 community-recruited Black MSM in HPTN 061, a multi-component HIV prevention intervention feasibility study. Sexual network composition, size, and density (extent to which members are having sex with one another) were compared by self-reported HIV serostatus and age of the men. GEE models assessed network and other factors associated with having a Black sex partner, having a partner with at least two age category difference (age difference between participant and partner of at least two age group categories), and having serodiscordant/serostatus unknown unprotected anal/vaginal intercourse (SDUI) in the last six months. Over half had exclusively Black partners in the last six months, 46% had a partner of at least two age category difference, 87% had ≤5 partners. Nearly 90% had sex partners who were also part of their social networks. Among HIV-negative men, not having anonymous/exchange/ trade partners and lower density were associated with having a Black partner; larger sexual network size and having non-primary partners were associated with having a partner with at least two age category difference; and having anonymous/exchange/ trade partners was associated with SDUI. Among HIV-positive men, not having non-primary partners was associated with having a Black partner; no sexual network characteristics were associated with having a partner with at least two age category difference and SDUI. Black MSM sexual networks were relatively small and often overlapped with the social networks. Sexual risk was associated with having non-primary partners and larger network size. Network interventions that engage the social networks of Black MSM, such as interventions utilizing peer influence, should be developed to address stable partnerships, number of partners, and serostatus disclosure.

Female brain size affects the assessment of male attractiveness during mate choice.

PubMed

Corral-López, Alberto; Bloch, Natasha I; Kotrschal, Alexander; van der Bijl, Wouter; Buechel, Severine D; Mank, Judith E; Kolm, Niclas

2017-03-01

Mate choice decisions are central in sexual selection theory aimed to understand how sexual traits evolve and their role in evolutionary diversification. We test the hypothesis that brain size and cognitive ability are important for accurate assessment of partner quality and that variation in brain size and cognitive ability underlies variation in mate choice. We compared sexual preference in guppy female lines selected for divergence in relative brain size, which we have previously shown to have substantial differences in cognitive ability. In a dichotomous choice test, large-brained and wild-type females showed strong preference for males with color traits that predict attractiveness in this species. In contrast, small-brained females showed no preference for males with these traits. In-depth analysis of optomotor response to color cues and gene expression of key opsins in the eye revealed that the observed differences were not due to differences in visual perception of color, indicating that differences in the ability to process indicators of attractiveness are responsible. We thus provide the first experimental support that individual variation in brain size affects mate choice decisions and conclude that differences in cognitive ability may be an important underlying mechanism behind variation in female mate choice.

Pelvic dimorphism in relation to body size and body size dimorphism in humans.

PubMed

Kurki, Helen K

2011-12-01

Many mammalian species display sexual dimorphism in the pelvis, where females possess larger dimensions of the obstetric (pelvic) canal than males. This is contrary to the general pattern of body size dimorphism, where males are larger than females. Pelvic dimorphism is often attributed to selection relating to parturition, or as a developmental consequence of secondary sexual differentiation (different allometric growth trajectories of each sex). Among anthropoid primates, species with higher body size dimorphism have higher pelvic dimorphism (in converse directions), which is consistent with an explanation of differential growth trajectories for pelvic dimorphism. This study investigates whether the pattern holds intraspecifically in humans by asking: Do human populations with high body size dimorphism also display high pelvic dimorphism? Previous research demonstrated that in some small-bodied populations, relative pelvic canal size can be larger than in large-bodied populations, while others have suggested that larger-bodied human populations display greater body size dimorphism. Eleven human skeletal samples (total N: male = 229, female = 208) were utilized, representing a range of body sizes and geographical regions. Skeletal measurements of the pelvis and femur were collected and indices of sexual dimorphism for the pelvis and femur were calculated for each sample [ln(M/F)]. Linear regression was used to examine the relationships between indices of pelvic and femoral size dimorphism, and between pelvic dimorphism and female femoral size. Contrary to expectations, the results suggest that pelvic dimorphism in humans is generally not correlated with body size dimorphism or female body size. These results indicate that divergent patterns of dimorphism exist for the pelvis and body size in humans. Implications for the evaluation of the evolution of pelvic dimorphism and rotational childbirth in Homo are considered. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sexual selection on the multicomponent display of black morph male Girardinus metallicus (Pisces: Poeciliidae).

PubMed

Wojan, E M; Bertram, S M; Clendenen, D A; Castillo, C; Neldner, H M; Kolluru, G R

2018-05-01

Sexually selected displays often include suites of integrated traits. Black morph males of the poeciliid fish Girardinus metallicus perform courtship and aggressive displays that exhibit their conspicuous yellow and black coloration. Body size, gonopodium size and ventral black area are correlated with intermale aggression, which is key for access to mates. A previous study showed that females may prefer dominant males prior to watching them fight; however, that result was obtained in trials that allowed for male-male interactions across partitions, and to date no study has uncovered the traits important in female choice. We performed a more comprehensive investigation of the multicomponent sexual display including measures of male yellow hue, saturation and brightness. We examined the behavior of size-matched males paired to maximize the difference in yellow saturation, and measured female choice exclusive of male-male interactions and chemical cues. We found no female preference for any traits in the multicomponent sexual display. Males with brighter and more saturated yellow coloration were more likely to be dominant, and dominant males courted and attempted copulations more. Our results suggest that yellow coloration is sexually selected; however, the courtship display requires further investigation because we did not identify targets of female preference, and we discuss possible explanations for this finding. Copyright © 2018 Elsevier B.V. All rights reserved.

Wing morphometrics of Aedes (Ochlerotatus) albifasciatus (Macquart, 1838) (Diptera: Culicidae) from different climatic regions of Argentina.

PubMed

Garzón, Maximiliano J; Schweigmann, Nicolás

2018-05-16

Gene flow restrictions between populations of Aedes albifasciatus, the vector of Western equine encephalitis and Dirophilaria immitis, have been described in the central region of Argentina. Genetic and eco-physiological variations usually result in local forms reflecting the climatic regions. Mosquito wings and their different parts have ecological functions in flight and communication. Therefore, wing shape could be considered an aspect of sexual dimorphism, and its eco-physiological responses can be expressed as morphological changes induced by the environment. To compare the geographical and sexual variations with respect to wing shape and size in two Ae. albifasciatus populations from contrasting climates of Argentina (temperate: Buenos Aires, and the arid steppe of Patagonia: Sarmiento), the wings of adults reared in thermal trays at different constant temperatures (10-29 °C) were analyzed. The wing size of Ae. albifasciatus showed inverse linear relationships with the rearing thermal condition and higher slope for Buenos Aires. In the cool range (10-17 °C), geographical size variations responded to the converse Bergmann's rule, where Buenos Aires individuals were larger than those from Sarmiento. Sexual shape dimorphism occurred in both populations while geographical variation in shape was observed in both sexes. Buenos Aires individuals showed greater response sensitivity with respect to the size-temperature relation than those from Sarmiento. The converse Bergmann's rule in size variation could be due to a higher development rate in Sarmiento to produce more cohorts in the limited favorable season. The shape could be more relevant with respect to the size in the study of population structures due to the size being more liable to vary due to changes in the environment. The geographical variations with respect to morphology could be favored by the isolation between populations and adaptations to the environmental conditions. Our results demonstrate that the shape and size of wing provide useful phenotypic information for studies related to sexual and environmental adaptations.

Life-history variation and allometry for sexual size dimorphism in Pacific salmon and trout

PubMed Central

Young, Kyle A.

2005-01-01

Allometry for sexual size dimorphism (SSD) is common in animals, but how different evolutionary processes interact to determine allometry remains unclear. Among related species SSD (male:female) typically increases with average body size, resulting in slopes of less than 1 when female size is regressed on male size: an allometric relationship formalized as ‘Rensch's rule’ . Empirical studies show that taxa with male-biased SSD are more likely to satisfy Rensch's rule and that a taxon's mean SSD is negatively correlated with allometric slope, implicating sexual selection on male size as an important mechanism promoting allometry for SSD. I use body length (and life-history) data from 628 (259) populations of seven species of anadromous Pacific salmon and trout (Oncorhynchus spp.) to show that in this genus life-history variation appears to regulate patterns of allometry both within and between species. Although all seven species have intraspecific allometric slopes of less than 1, contrary to expectation slope is unrelated to species' mean SSD, but is instead negatively correlated with two life-history variables: the species' mean marine age and variation in marine age. Second, because differences in marine age among species render SSD and body size uncorrelated, the interspecific slope is isometric. Together, these results provide an example of how evolutionary divergence in life history among related species can affect patterns of allometry for SSD across taxonomic scales. PMID:15695207

Sex biased expression of ghrelin and GHSR associated with sexual size dimorphism in yellow catfish.

PubMed

Zhang, Jin; Ma, Wenge; He, Yan; Wu, Junjie; Dawar, Farman Ullah; Ren, Fan; Zhao, Xiaohan; Mei, Jie

2016-03-10

Sexual size dimorphism has been observed in many cultivable fish species including yellow catfish, in which male fish grow much faster than female fish. Ghrelin is a potent stimulator of pituitary growth hormone (GH) release and known to potentially promote food intake and body weight gain. In order to investigate the molecular mechanism of sexual size dimorphism in yellow catfish (Pelteobagrus fulvidraco), ghrelin and its functional receptor, growth hormone secretagogue receptor (GHSR) cDNAs were cloned. Real-time PCR indicated that both ghrelin and GHSR were more highly expressed in hypothalamus and gut of male fish than female. During normal larval development, expression of ghrelin and GHSR genes was significantly higher in males than in females. 17a-Methyltestosterone (MT) treatment enhanced the expression of ghrelin in female larval fish and GHSR in both sexes, whereas the expression of ghrelin in male larval fish increased in the beginning, then decreased as the treatment time prolonged. Furthermore, the expression of ghrelin and GHSR in male juvenile was significantly increased compared with female juvenile, in short and long term fasting periods, suggesting that male fish may have a better appetite than female during fasting. Our results demonstrate that sex difference in the expression of ghrelin and GHSR may be involved in sexual size dimorphism by regulating feeding and GH/IGF signaling in yellow catfish. Copyright © 2015 Elsevier B.V. All rights reserved.

Self-healing mortar with pH-sensitive superabsorbent polymers: testing of the sealing efficiency by water flow tests

NASA Astrophysics Data System (ADS)

Gruyaert, Elke; Debbaut, Brenda; Snoeck, Didier; Díaz, Pilar; Arizo, Alejandro; Tziviloglou, Eirini; Schlangen, Erik; De Belie, Nele

2016-08-01

Superabsorbent polymers (SAPs) have potential to be used as healing agent in self-healing concrete due to their property to attract moisture from the environment and their capacity to promote autogenous healing. A possible drawback, however, is their uptake of mixing water during concrete manufacturing, resulting in an increased volume of macro-pores in the hardened concrete. To limit this drawback, newly developed SAPs with a high swelling and pH-sensitiveness were developed and tested within the FP7 project HEALCON. Evaluation of their self-sealing performance occurred through a water permeability test via water flow, a test method also developed within HEALCON. Three different sizes of the newly developed SAP were compared with a commercial SAP. Swelling tests in cement filtrate solution indicated that the commercial and in-house synthesized SAPs performed quite similar, but the difference between the swelling capacity at pH 9 and pH 13 is more pronounced for the self-synthesized SAPs. Moreover, in comparison to the commercial SAPs, less macro-pores are formed in the cement matrix of mixes with self-synthesized SAPs and the effect on the mechanical properties is lower, but not negligible, when using high amounts of SAPs. Although the immediate sealing effect of cracks in mortar was the highest for the commercial SAPs, the in-house made SAPs with a particle size between 400 and 600 μm performed the best with regard to crack closure (mainly CaCO3 precipitation) and self-sealing efficiency, after exposing the specimens to 28 wet-dry cycles. Some specimens could even withstand a water pressure of 2 bar.

Evolution of body size in Galapagos marine iguanas.

PubMed

Wikelski, Martin

2005-10-07

Body size is one of the most important traits of organisms and allows predictions of an individual's morphology, physiology, behaviour and life history. However, explaining the evolution of complex traits such as body size is difficult because a plethora of other traits influence body size. Here I review what we know about the evolution of body size in a group of island reptiles and try to generalize about the mechanisms that shape body size. Galapagos marine iguanas occupy all 13 larger islands in this Pacific archipelago and have maximum island body weights between 900 and 12 000g. The distribution of body sizes does not match mitochondrial clades, indicating that body size evolves independently of genetic relatedness. Marine iguanas lack intra- and inter-specific food competition and predators are not size-specific, discounting these factors as selective agents influencing body size. Instead I hypothesize that body size reflects the trade-offs between sexual and natural selection. We found that sexual selection continuously favours larger body sizes. Large males establish display territories and some gain over-proportional reproductive success in the iguanas' mating aggregations. Females select males based on size and activity and are thus responsible for the observed mating skew. However, large individuals are strongly selected against during El Niño-related famines when dietary algae disappear from the intertidal foraging areas. We showed that differences in algae sward ('pasture') heights and thermal constraints on large size are causally responsible for differences in maximum body size among populations. I hypothesize that body size in many animal species reflects a trade-off between foraging constraints and sexual selection and suggest that future research could focus on physiological and genetic mechanisms determining body size in wild animals. Furthermore, evolutionary stable body size distributions within populations should be analysed to better understand selection pressures on individual body size.

Evolution of body size in Galapagos marine iguanas

PubMed Central

Wikelski, Martin

2005-01-01

Body size is one of the most important traits of organisms and allows predictions of an individual's morphology, physiology, behaviour and life history. However, explaining the evolution of complex traits such as body size is difficult because a plethora of other traits influence body size. Here I review what we know about the evolution of body size in a group of island reptiles and try to generalize about the mechanisms that shape body size. Galapagos marine iguanas occupy all 13 larger islands in this Pacific archipelago and have maximum island body weights between 900 and 12 000 g. The distribution of body sizes does not match mitochondrial clades, indicating that body size evolves independently of genetic relatedness. Marine iguanas lack intra- and inter-specific food competition and predators are not size-specific, discounting these factors as selective agents influencing body size. Instead I hypothesize that body size reflects the trade-offs between sexual and natural selection. We found that sexual selection continuously favours larger body sizes. Large males establish display territories and some gain over-proportional reproductive success in the iguanas' mating aggregations. Females select males based on size and activity and are thus responsible for the observed mating skew. However, large individuals are strongly selected against during El Niño-related famines when dietary algae disappear from the intertidal foraging areas. We showed that differences in algae sward (‘pasture’) heights and thermal constraints on large size are causally responsible for differences in maximum body size among populations. I hypothesize that body size in many animal species reflects a trade-off between foraging constraints and sexual selection and suggest that future research could focus on physiological and genetic mechanisms determining body size in wild animals. Furthermore, evolutionary stable body size distributions within populations should be analysed to better understand selection pressures on individual body size. PMID:16191607

Sexual selection targets cetacean pelvic bones

PubMed Central

Dines, J. P.; Otárola-Castillo, E.; Ralph, P.; Alas, J.; Daley, T.; Smith, A. D.; Dean, M. D.

2014-01-01

Male genitalia evolve rapidly, probably as a result of sexual selection. Whether this pattern extends to the internal infrastructure that influences genital movements remains unknown. Cetaceans (whales and dolphins) offer a unique opportunity to test this hypothesis: since evolving from land-dwelling ancestors, they lost external hind limbs and evolved a highly reduced pelvis which seems to serve no other function except to anchor muscles that maneuver the penis. Here we create a novel morphometric pipeline to analyze the size and shape evolution of pelvic bones from 130 individuals (29 species) in the context of inferred mating system. We present two main findings: 1) males from species with relatively intense sexual selection (inferred by relative testes size) have evolved relatively large penises and pelvic bones compared to their body size, and 2) pelvic bone shape diverges more quickly in species pairs that have diverged in inferred mating system. Neither pattern was observed in the anterior-most pair of vertebral ribs, which served as a negative control. This study provides evidence that sexual selection can affect internal anatomy that controls male genitalia. These important functions may explain why cetacean pelvic bones have not been lost through evolutionary time. PMID:25186496

The handicap process favors exaggerated, rather than reduced, sexual ornaments.

PubMed

Tazzyman, Samuel J; Iwasa, Yoh; Pomiankowski, Andrew

2014-09-01

Why are traits that function as secondary sexual ornaments generally exaggerated in size compared to the naturally selected optimum, and not reduced? Because they deviate from the naturally selected optimum, traits that are reduced in size will handicap their bearer, and could thus provide an honest signal of quality to a potential mate. Thus if secondary sexual ornaments evolve via the handicap process, current theory suggests that reduced ornamentation should be as frequent as exaggerated ornamentation, but this is not the case. To try to explain this discrepancy, we analyze a simple model of the handicap process. Our analysis shows that asymmetries in costs of preference or ornament with regard to exaggeration and reduction cannot fully explain the imbalance. Rather, the bias toward exaggeration can be best explained if either the signaling efficacy or the condition dependence of a trait increases with size. Under these circumstances, evolution always leads to more extreme exaggeration than reduction: although the two should occur just as frequently, exaggerated secondary sexual ornaments are likely to be further removed from the naturally selected optimum than reduced ornaments. © 2014 The Authors. Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Sexual dimorphism and feeding ecology of Diamond-backed Terrapins (Malaclemys terrapin)

USGS Publications Warehouse

Underwood, Elizabeth B.; Bowers, Sarah; Guzy, Jacquelyn C.; Lovich, Jeffrey E.; Taylor, Carole A.; Gibbons, J. Whitfield; Dorcas, Michael E.

2013-01-01

Natural and sexual selection are frequently invoked as causes of sexual size dimorphism in animals. Many species of turtles, including the Diamond-backed Terrapin (Malaclemys terrapin), exhibit sexual dimorphism in body size, possibly enabling the sexes to exploit different resources and reduce intraspecific competition. Female terrapins not only have larger body sizes but also disproportionately larger skulls and jaws relative to males. To better understand the relationship between skull morphology and terrapin feeding ecology, we measured the in-lever to out-lever ratios of 27 male and 33 female terrapin jaws to evaluate biomechanics of the trophic apparatus. In addition, we measured prey handling times by feeding Fiddler Crabs (Uca pugnax), a natural prey item, to 24 terrapins in the laboratory. Our results indicate that although females have disproportionately larger heads, they have similar in:out lever ratios to males, suggesting that differences in adductor muscle mass are more important in determining bite force than jaw in:out lever ratios. Females also had considerably reduced prey handling times. Understanding the factors affecting terrapin feeding ecology can illuminate the potential roles male and female terrapins play as top-down predators that regulate grazing of Periwinkle Snails (Littorina irrorata) on Cord Grass (Spartina alterniflora).

Sialolipoma of salivary glands: Two case reports and review of the literature

PubMed Central

Khazaeni, Kamran; Jafarian, Amir Hosein; Khajehahmadi, Saeedeh; Rahpeyma, Amin; Asadi, Ladan

2013-01-01

Sialolipoma is a rare neoplasm of salivary glands, described as a distinct entity by Nagao et al. in 2001. Thirty-six cases of sialolipoma in minor and major salivary glands have been reported thus far in addition to the two new cases of sialolipoma arising in the major salivary glands in this study. Thirty-six cases of sialolipoma published in English language reports were analyzed considering gender, age, location, size, duration of symptoms, treatment mode, follow-up, and histologic findings. Congenital sialolipomas were considered in this study. The first case occurred in a 45-year-old female and presented as a localized swelling in right parotid area. The second case occurred in an 18-year-old female as a swelling in the left parotid region. On histopathological examination, these lesions were diagnosed as sialolipoma. PMID:23878570

IgG4-related Mikulicz's disease associated with thyroiditis: a case report and review of the literature.

PubMed

Zhang, Yujiao; Du, Yi; Li, Kaijun; He, Jianfeng

2014-03-01

To report an unusual case of IgG4-related Mikulicz's disease associated with thyroiditis. We describe a 25-year-old Chinese man who presented with bilateral, painless swellings of the lachrymal glands, parotid glands, and thyroid nodules. The patient underwent left-sided dacryoadenectomy and the diagnosis of IgG4-related Mikulicz's disease was pathologically confirmed. The size of the right-sided lachrymal gland and parotid glands recovered fundamentally after one month of glucocorticoid therapy. IgG4-related Mikulicz's disease associated with thyroiditis should be considered in the differential diagnosis of bilateral swellings of lachrymal glands, salivary glands, and thyroid nodules. Surgical excision is recommended in order to treat the tumor and to ensure the pathological diagnosis. Glucocorticoid therapy should be considered in association with surgery after removal.

Analysis of intergranular fission-gas bubble-size distributions in irradiated uranium-molybdenum alloy fuel

NASA Astrophysics Data System (ADS)

Rest, J.; Hofman, G. L.; Kim, Yeon Soo

2009-04-01

An analytical model for the nucleation and growth of intra and intergranular fission-gas bubbles is used to characterize fission-gas bubble development in low-enriched U-Mo alloy fuel irradiated in the advanced test reactor in Idaho as part of the Reduced Enrichment for Research and Test Reactor (RERTR) program. Fuel burnup was limited to less than ˜7.8 at.% U in order to capture the fuel-swelling stage prior to irradiation-induced recrystallization. The model couples the calculation of the time evolution of the average intergranular bubble radius and number density to the calculation of the intergranular bubble-size distribution based on differential growth rate and sputtering coalescence processes. Recent results on TEM analysis of intragranular bubbles in U-Mo were used to set the irradiation-induced diffusivity and re-solution rate in the bubble-swelling model. Using these values, good agreement was obtained for intergranular bubble distribution compared against measured post-irradiation examination (PIE) data using grain-boundary diffusion enhancement factors of 15-125, depending on the Mo concentration. This range of enhancement factors is consistent with values obtained in the literature.

Physicochemical and mechanical properties of freeze cast hydroxyapatite-gelatin scaffolds with dexamethasone loaded PLGA microspheres for hard tissue engineering applications.

PubMed

Ghorbani, Farnaz; Nojehdehian, Hanieh; Zamanian, Ali

2016-12-01

Hydroxyapatite (HA)-gelatin scaffolds incorporated with dexamethasone-loaded polylactic-co-glycolic acid (PLGA) microspheres were synthesized by freeze casting technique. Scanning electron microscopy (SEM) micrographs demonstrated a unidirectional microstructure and a decrease in the pore size as a function of temperature gradient. Higher amounts of HA resulted in a decrease in the pore size. According to the results, at lower cooling rates, the formation of a lamellar structure decreased the mechanical strength, but at the same time, enhanced the swelling ratio, biodegradation rate and drug release level. On the other hand, higher weight ratios of HA increased the compressive strength, and reduced the swelling ratio, biodegradation rate and drug release level. The results obtained by furrier transform infrared spectroscopy (FTIR) and bioactivity analysis illustrated that the interactions of the materials support the apatite formation in the simulated body fluid (SBF) solution. Based on the obtained results, the synthesized composite scaffolds have the necessary mechanical and physicochemical features to support the regeneration of defects and to maintain their stability during the neo-tissue formation. Copyright © 2016 Elsevier B.V. All rights reserved.

Tunable thermo-responsive hydrogels: synthesis, structural analysis and drug release studies.

PubMed

Cirillo, Giuseppe; Spataro, Tania; Curcio, Manuela; Spizzirri, U Gianfranco; Nicoletta, Fiore Pasquale; Picci, Nevio; Iemma, Francesca

2015-03-01

Thermo-responsive hydrogel films, synthesized by UV-initiated radical polymerization, are proposed as delivery devices for non-steroidal anti-inflammatory drugs (Diclofenac sodium and Naproxen). N-isopropylacrylamide and N,N'-ethylenebisacrylamide were chosen as thermo-sensitive monomer and crosslinker, respectively. Infrared spectroscopy was used to assess the incorporation of monomers into the network, and the network density of hydrogel films was found to strictly depend on both feed composition and film thickness. Calorimetric analyses showed negative thermo-responsive behaviour with shrinking/swelling transition values in the range 32.8-36.1°C. Equilibrium swelling studies around the LCST allowed the correlation between the structural changes and the temperature variations. The mesh size, indeed, rapidly changed from a collapsed to a swollen state, with beneficial effects in applications such as size-selective permeation or controlled drug delivery, while the crosslinking degree, the film thickness, and the loading method deeply influenced the drug release profiles at 25 and 40°C. The analysis of both 3D-network structure, release kinetics and diffusional constraints at different temperatures was evaluated by mathematical modelling. Copyright © 2014 Elsevier B.V. All rights reserved.

Female sexual arousal disorder with and without a distress criterion: prevalence and correlates in a representative Czech sample.

PubMed

Weiss, Petr; Brody, Stuart

2009-12-01

Sexual medicine would benefit from large representative surveys examining the prevalence of genital female sexual arousal disorder (FSAD) symptoms (with and without the increasingly controversial distress criterion), as well as novel FSAD correlates and potential "protective" factors. To examine the extent to which genital FSAD symptoms, with and without a distress criterion, are associated with both historical and current aspects of sexual behavior. In a representative sample of the Czech population (aged 15-88), 1,000 women were asked whether they currently have impaired lubrication and vaginal swelling (and if so, if this produces marked distress or interpersonal difficulty). They provided details of vaginal orgasm (induced by penile-vaginal intercourse [PVI] without clitoral masturbation) consistency, feelings during their first PVI, estimates of their typical foreplay and PVI durations, their degree of mental focus on vaginal sensations during PVI, among other factors. The current prevalence of FSAD with and without a distress criterion and their associations with current and antecedent sexual behaviors and responses. The current prevalence of FSAD was 10.3% without, plus 7.5% with a distress criterion (which tended to be associated with more impairments than without distress). History of vaginal orgasm (odds ratio = 2.78), never masturbating (odds ratio = 2.4), not having felt pain and discomfort on first PVI (odds ratio = 2.27), and not having frequent anal intercourse are protective against FSAD with distress, but not without distress. Age (especially over 50) and inadequate focusing of mental attention on vaginal sensations during PVI are associated with increased FSAD risk both with and without distress. FSAD with and without distress appear to be different entities to some extent, with the distressed group showing more long-term signs of psychosexual impairment. We suggest that FSAD with and without distress be considered two different disorders.

Plasma Testosterone Levels Increase with Expression of Male Ornaments During Mating, but not Incubation, in Japanese Barn Swallows.

PubMed

Hasegawa, Masaru; Arai, Emi; Sato, Megumi; Sakai, Hidetsugu

2017-08-01

Recent experimental studies involving the manipulation of sexual traits have demonstrated that sexual trait expression feeds back to testosterone levels, perhaps via social interactions, reinforcing the linkage between sexual trait expression and testosterone levels during the mating period. However, information on this reinforcement under the natural variation of sexual traits remains limited. Using Japanese barn swallows, Hirundo rustica gutturalis, in which extra-pair paternity is quite rare (< 3%), we studied the relationship between plasma testosterone level and a male sexual trait, throat patch size, during the mating and incubation periods. Given the importance of social interaction, we predicted that this relationship should be intense during the mating period, but not the incubation period, due to reduced social interaction during the latter. We found low plasma testosterone levels during the incubation period compared with those in the mating period, and plasma testosterone levels were significantly positively related to throat patch area during the mating period, but not the incubation period. Similar relationships were found in another sexual trait, the size of white tail spots. During the incubation period, body condition, instead of male sexual trait expression, was negatively related to plasma testosterone level, indicating that an intrinsic link, rather than reinforcement, is important during this period. These relationships are consistent with the hypothesis that social interaction reinforces the relationship between sexual traits and plasma testosterone levels. The current study provides evidence for a highly variable relationship between testosterone and ornamentation across breeding periods in the natural variation of sexual traits.

Male Weaponry in a Fighting Cricket

PubMed Central

Judge, Kevin A.; Bonanno, Vanessa L.

2008-01-01

Sexually selected male weaponry is widespread in nature. Despite being model systems for the study of male aggression in Western science and for cricket fights in Chinese culture, field crickets (Orthoptera, Gryllidae, Gryllinae) are not known to possess sexually dimorphic weaponry. In a wild population of the fall field cricket, Gryllus pennsylvanicus, we report sexual dimorphism in head size as well as the size of mouthparts, both of which are used when aggressive contests between males escalate to physical combat. Male G. pennsylvanicus have larger heads, maxillae and mandibles than females when controlling for pronotum length. We conducted two experiments to test the hypothesis that relatively larger weaponry conveys an advantage to males in aggressive contests. Pairs of males were selected for differences in head size and consequently were different in the size of maxillae and mandibles. In the first experiment, males were closely matched for body size (pronotum length), and in the second, they were matched for body mass. Males with proportionately larger weaponry won more fights and increasing differences in weaponry size between males increased the fighting success of the male with the larger weaponry. This was particularly true when contests escalated to grappling, the most intense level of aggression. However, neither contest duration nor intensity was related to weaponry size as predicted by models of contest settlement. These results are the first evidence that the size of the head capsule and mouthparts are under positive selection via male-male competition in field crickets, and validate 800-year-old Chinese traditional knowledge. PMID:19107188

The evolution of sexual size dimorphism in the house finch. II. Population divergence in relation to local selection.

PubMed

Badyaev, A V; Hill, G E; Stoehr, A M; Nolan, P M; McGraw, K J

2000-12-01

Recent colonization of ecologically distinct areas in North America by the house finch (Carpodacus mexicanus) was accompanied by strong population divergence in sexual size dimorphism. Here we examined whether this divergence was produced by population differences in local selection pressures acting on each sex. In a long-term study of recently established populations in Alabama, Michigan, and Montana, we examined three selection episodes for each sex: selection for pairing success, overwinter survival, and within-season fecundity. Populations varied in intensity of these selection episodes, the contribution of each episode to the net selection, and in the targets of selection. Direction and intensity of selection strongly differed between sexes, and different selection episodes often favored opposite changes in morphological traits. In each population, current net selection for sexual dimorphism was highly concordant with observed sexual dimorphism--in each population, selection for dimorphism was the strongest on the most dimorphic traits. Strong directional selection on sexually dimorphic traits, and similar intensities of selection in both sexes, suggest that in each of the recently established populations, both males and females are far from their local fitness optimum, and that sexual dimorphism has arisen from adaptive responses in both sexes. Population differences in patterns of selection on dimorphism, combined with both low levels of ontogenetic integration in heritable sexually dimorphic traits and sexual dimorphism in growth patterns, may account for the close correspondence between dimorphism in selection and observed dimorphism in morphology across house finch populations.

Specific-age group sex estimation of infants through geometric morphometrics analysis of pubis and ischium.

PubMed

Estévez Campo, Enrique José; López-Lázaro, Sandra; López-Morago Rodríguez, Claudia; Alemán Aguilera, Inmaculada; Botella López, Miguel Cecilio

2018-05-01

Sex determination of unknown individuals is one of the primary goals of Physical and Forensic Anthropology. The adult skeleton can be sexed using both morphological and metric traits on a large number of bones. The human pelvis is often used as an important element of adult sex determination. However, studies carried out about the pelvic bone in subadult individuals present several limitations due the absence of sexually dimorphic characteristics. In this study, we analyse the sexual dimorphism of the immature pubis and ischium bones, attending to their shape (Procrustes residuals) and size (centroid size), using an identified sample of subadult individuals composed of 58 individuals for the pubis and 83 for the ischium, aged between birth and 1year of life, from the Granada osteological collection of identified infants (Granada, Spain). Geometric morphometric methods and discriminant analysis were applied to this study. The results of intra- and inter-observer error showed good and excellent agreement in the location of coordinates of landmarks and semilandmarks, respectively. Principal component analysis performed on shape and size variables showed superposition of the two sexes, suggesting a low degree of sexual dimorphism. Canonical variable analysis did not show significant changes between the male and female shapes. As a consequence, discriminant analysis with leave-one-out cross validation provided low classification accuracy. The results suggested a low degree of sexual dimorphism supported by significant sexual dimorphism in the subadult sample and poor cross-validated classification accuracy. The inclusion of centroid size as a discriminant variable does not imply a significant improvement in the results of the analysis. The similarities found between the sexes prevent consideration of pubic and ischial morphology as a sex estimator in early stages of development. The authors suggest extending this study by analysing the different trajectories of shape and size in later ontogeny between males and females. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparative biology of the crab Goniopsis cruentata: geographic variation of body size, sexual maturity, and allometric growth

NASA Astrophysics Data System (ADS)

de Lira, José Jonathas Pereira Rodrigues; Calado, Tereza Cristina dos Santos; Rezende, Carla Ferreira; Silva, José Roberto Feitosa

2015-12-01

Geographic variation of phenotypic traits is common across species and is often associated with variation in environmental conditions. Here, we found larger bodies and larger size at maturity in a northward, lower latitude population of the crab Goniopsis cruentata, which inhabits a hotter, drier environment in comparison with a southward, higher latitude population. Furthermore, the juvenile male gonopods grow more relative to body size in the population characterized by maturation at a smaller size. In contrast, the female abdomen widens at a higher rate among the late maturing population. These results provide further evidence that local environmental conditions play a role in phenotypic variation between populations inhabiting different latitudes. Moreover, they also show that variation in size at maturity and body size can lead to divergent allometric patterns of sexual characteristics that can have a sex-specific response.

The role of foraging behaviour in the sexual segregation of the African elephant.

PubMed

Shannon, Graeme; Page, Bruce R; Duffy, Kevin J; Slotow, Rob

2006-11-01

Elephants (Loxodonta africana) exhibit pronounced sexual dimorphism, and in this study we test the prediction that the differences in body size and sociality are significant enough to drive divergent foraging strategies and ultimately sexual segregation. Body size influences the foraging behaviour of herbivores through the differential scaling coefficients of metabolism and gut size, with larger bodied individuals being able to tolerate greater quantities of low-quality, fibrous vegetation, whilst having lower mass-specific energy requirements. We test two distinct theories: the scramble competition hypothesis (SCH) and the forage selection hypothesis (FSH). Comprehensive behavioural data were collected from the Pongola Game Reserve and the Phinda Private Game Reserve in South Africa over a 2.5-year period. The data were analysed using sex as the independent variable. Adult females targeted a wider range of species, adopted a more selective foraging approach and exhibited greater bite rates as predicted by the body size hypothesis and the increased demands of reproductive investment (lactation and pregnancy). Males had longer feeding bouts, displayed significantly more destructive behaviour (31% of observations, 11% for females) and ingested greater quantities of forage during each feeding bout. The independent ranging behaviour of adult males enables them to have longer foraging bouts as they experience fewer social constraints than females. The SCH was rejected as a cause of sexual segregation due to the relative abundance of low quality forage, and the fact that feeding heights were similar for both males and females. However, we conclude that the differences in the foraging strategies of the sexes are sufficient to cause spatial segregation as postulated by the FSH. Sexual dimorphism and the associated behavioural differences have important implications for the management and conservation of elephant and other dimorphic species, with the sexes effectively acting as distinct "ecological species".

Parabolic variation in sexual selection intensity across the range of a cold-water pipefish: implications for susceptibility to climate change.

PubMed

Monteiro, Nuno; Cunha, Mário; Ferreira, Lídia; Vieira, Natividade; Antunes, Agostinho; Lyons, David; Jones, Adam G

2017-09-01

While an understanding of evolutionary processes in shifting environments is vital in the context of rapid ecological change, one of the most potent selective forces, sexual selection, remains curiously unexplored. Variation in sexual selection across a species range, especially across a gradient of temperature regimes, has the potential to provide a window into the possible impacts of climate change on the evolution of mating patterns. Here, we investigated some of the links between temperature and indicators of sexual selection, using a cold-water pipefish as model. We found that populations differed with respect to body size, length of the breeding season, fecundity, and sexual dimorphism across a wide latitudinal gradient. We encountered two types of latitudinal patterns, either linear, when related to body size, or parabolic in shape when considering variables related to sexual selection intensity, such as sexual dimorphism and reproductive investment. Our results suggest that sexual selection intensity increases toward both edges of the distribution and that the large differences in temperature likely play a significant role. Shorter breeding seasons in the north and reduced periods for gamete production in the south certainly have the potential to alter mating systems, breeding synchrony, and mate monopolization rates. As latitude and water temperature are tightly coupled across the European coasts, the observed patterns in traits related to sexual selection can lead to predictions regarding how sexual selection should change in response to climate change. Based on data from extant populations, we can predict that as the worm pipefish moves northward, a wave of decreasing selection intensity will likely replace the strong sexual selection at the northern range margin. In contrast, the southern populations will be followed by heightened sexual selection, which may exacerbate the problem of local extinction at this retreating boundary. © 2017 John Wiley & Sons Ltd.

Demographic consequences of greater clonal than sexual reproduction in Dicentra canadensis.

PubMed

Lin, Chia-Hua; Miriti, Maria N; Goodell, Karen

2016-06-01

Clonality is a widespread life history trait in flowering plants that may be essential for population persistence, especially in environments where sexual reproduction is unpredictable. Frequent clonal reproduction, however, could hinder sexual reproduction by spatially aggregating ramets that compete with seedlings and reduce inter-genet pollination. Nevertheless, the role of clonality in relation to variable sexual reproduction in population dynamics is often overlooked. We combined population matrix models and pollination experiments to compare the demographic contributions of clonal and sexual reproduction in three Dicentra canadensis populations, one in a well-forested landscape and two in isolated forest remnants. We constructed stage-based transition matrices from 3 years of census data to evaluate annual population growth rates, λ. We used loop analysis to evaluate the relative contribution of different reproductive pathways to λ. Despite strong temporal and spatial variation in seed set, populations generally showed stable growth rates. Although we detected some pollen limitation of seed set, manipulative pollination treatments did not affect population growth rates. Clonal reproduction contributed significantly more than sexual reproduction to population growth in the forest remnants. Only at the well-forested site did sexual reproduction contribute as much as clonal reproduction to population growth. Flowering plants were more likely to transition to a smaller size class with reduced reproductive potential in the following year than similarly sized nonflowering plants, suggesting energy trade-offs between sexual and clonal reproduction at the individual level. Seed production had negligible effects on growth and tuber production of individual plants. Our results demonstrate that clonal reproduction is vital for population persistence in a system where sexual reproduction is unpredictable. The bias toward clonality may be driven by low fitness returns for resource investment in sexual reproduction at the individual level. However, chronic failure in sexual reproduction may exacerbate the imbalance between sexual and clonal reproduction and eventually lead to irreversible loss of sex in the population.

Modeling multidomain hydraulic properties of shrink-swell soils

NASA Astrophysics Data System (ADS)

Stewart, Ryan D.; Abou Najm, Majdi R.; Rupp, David E.; Selker, John S.

2016-10-01

Shrink-swell soils crack and become compacted as they dry, changing properties such as bulk density and hydraulic conductivity. Multidomain models divide soil into independent realms that allow soil cracks to be incorporated into classical flow and transport models. Incongruously, most applications of multidomain models assume that the porosity distributions, bulk density, and effective saturated hydraulic conductivity of the soil are constant. This study builds on a recently derived soil shrinkage model to develop a new multidomain, dual-permeability model that can accurately predict variations in soil hydraulic properties due to dynamic changes in crack size and connectivity. The model only requires estimates of soil gravimetric water content and a minimal set of parameters, all of which can be determined using laboratory and/or field measurements. We apply the model to eight clayey soils, and demonstrate its ability to quantify variations in volumetric water content (as can be determined during measurement of a soil water characteristic curve) and transient saturated hydraulic conductivity, Ks (as can be measured using infiltration tests). The proposed model is able to capture observed variations in Ks of one to more than two orders of magnitude. In contrast, other dual-permeability models assume that Ks is constant, resulting in the potential for large error when predicting water movement through shrink-swell soils. Overall, the multidomain model presented here successfully quantifies fluctuations in the hydraulic properties of shrink-swell soil matrices, and are suitable for use in physical flow and transport models based on Darcy's Law, the Richards Equation, and the advection-dispersion equation.

Transient swelling of the Schneiderian membrane after transversal sinus augmentation: a pilot study.

PubMed

Quirynen, Marc; Lefever, David; Hellings, Peter; Jacobs, Reinhilde

2014-01-01

The predictability and simplicity of the Summers' technique for sinus floor elevation encouraged many clinicians to consider this new approach. The impact of such intervention on the sinus mucosa has, however, not been explored extensively. This pilot study followed the response of the Schneiderian membrane, longitudinally, via cone-beam CT images. Ten consecutive patients (five women, mean age 58.7 years) referred for implant therapy in the posterior part of the maxilla, in combination with a trans-alveolar sinus floor elevation (13 sinuses involved), were enrolled. CBCT images were taken prior to and at 1 week and 1 month after surgery. The changes in thickness of the Schneiderian membrane were scored at nine standardized points per sinus using reformatted cross-sectional images. One week after sinus floor elevation, the Schneiderian membrane showed a significant swelling of 9.2 mm in the middle (SD 0.3; P < 0.005), 7.2 mm medially (SD 2.5; P < 0.005) and 3.9 mm laterally (SD 0,3; P < 0.05), respectively, resulting in an overall mean of 6.7 mm (SD 2.6), which fully disappeared 3 weeks later. This swelling involved the entire floor of the sinus and not only the augmented area. Within the limitations of this pilot study, one can conclude that the Schneiderian membrane responds with a significant "transient" swelling (5-10× its size) during the first weeks of healing. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Identification of Multiple QTLs Linked to Neuropathology in the Engrailed-1 Heterozygous Mouse Model of Parkinson’s Disease

PubMed Central

Kurowska, Zuzanna; Jewett, Michael; Brattås, Per Ludvik; Jimenez-Ferrer, Itzia; Kenéz, Xuyian; Björklund, Tomas; Nordström, Ulrika; Brundin, Patrik; Swanberg, Maria

2016-01-01

Motor symptoms in Parkinson’s disease are attributed to degeneration of midbrain dopaminergic neurons (DNs). Heterozygosity for Engrailed-1 (En1), one of the key factors for programming and maintenance of DNs, results in a parkinsonian phenotype featuring progressive degeneration of DNs in substantia nigra pars compacta (SNpc), decreased striatal dopamine levels and swellings of nigro-striatal axons in the SwissOF1-En1+/− mouse strain. In contrast, C57Bl/6-En1+/− mice do not display this neurodegenerative phenotype, suggesting that susceptibility to En1 heterozygosity is genetically regulated. Our goal was to identify quantitative trait loci (QTLs) that regulate the susceptibility to PD-like neurodegenerative changes in response to loss of one En1 allele. We intercrossed SwissOF1-En1+/− and C57Bl/6 mice to obtain F2 mice with mixed genomes and analyzed number of DNs in SNpc and striatal axonal swellings in 120 F2-En1+/− 17 week-old male mice. Linkage analyses revealed 8 QTLs linked to number of DNs (p = 2.4e-09, variance explained = 74%), 7 QTLs linked to load of axonal swellings (p = 1.7e-12, variance explained = 80%) and 8 QTLs linked to size of axonal swellings (p = 7.0e-11, variance explained = 74%). These loci should be of prime interest for studies of susceptibility to Parkinson’s disease-like damage in rodent disease models and considered in clinical association studies in PD. PMID:27550741

The Association between Penis Size and Sexual Health among Men Who Have Sex with Men

PubMed Central

Grov, Christian; Parsons, Jeffrey T.; Bimbi, David S.

2010-01-01

Larger penis size has been equated with a symbol of power, stamina, masculinity, and social status. Yet, there has been little research among men who have sex with men assessing the association between penis size and social-sexual health. Survey data from a diverse sample of 1,065 men who have sex with men were used to explore the association between perceived penis size and a variety of psychosocial outcomes. Seven percent of men felt their penis was “below average,” 53.9% “average,” and 35.5% “above average.” Penis size was positively related to satisfaction with size and inversely related to lying about penis size (all p < .01). Size was unrelated to condom use, frequency of sex partners, HIV status, or recent diagnoses of HBV, HCV, gonorrhea/Chlamydia/urinary tract infections, and syphilis. Men with above average penises were more likely to report HPV and HSV-2 (Fisher’s exact p ≤ .05). Men with below average penises were significantly more likely to identify as “bottoms” (anal receptive) and men with above average penises were significantly more likely to identify as tops (anal insertive). Finally, men with below average penises fared significantly worse than other men on three measures of psychosocial adjustment. Though most men felt their penis size was average, many fell outside this “norm.” The disproportionate number of viral skin-to-skin STIs (HSV-2 and HPV) suggest size may play a role in condom slippage/breakage. Further, size played a significant role in sexual positioning and psychosocial adjustment. These data highlight the need to better understand the real individual-level consequences of living in a penis-centered society. PMID:19139986

Differential Response of Neural Cells to Trauma-Induced Swelling In Vitro.

PubMed

Jayakumar, A R; Taherian, M; Panickar, K S; Shamaladevi, N; Rodriguez, M E; Price, B G; Norenberg, M D

2018-02-01

Brain edema and the associated increase in intracranial pressure are major consequences of traumatic brain injury (TBI) that accounts for most early deaths after TBI. We recently showed that acute severe trauma to cultured astrocytes results in cell swelling. We further examined whether trauma induces cell swelling in neurons and microglia. We found that severe trauma also caused cell swelling in cultured neurons, whereas no swelling was observed in microglia. While severe trauma caused cell swelling in both astrocytes and neurons, mild trauma to astrocytes, neurons, and microglia failed to cell swelling. Since extracellular levels of glutamate are increased in brain post-TBI and microglia are known to release cytokine, and direct exposure of astrocytes to these molecules are known to stimulate cell swelling, we examined whether glutamate or cytokines have any additive effect on trauma-induced cell swelling. Exposure of cultured astrocytes to trauma caused cell swelling, and such swelling was potentiated by the exposure of traumatized astrocytes to glutamate and cytokines. Conditioned medium (CM) from traumatized astrocytes had no effect on neuronal swelling post-trauma, while CM from traumatized neurons and microglia potentiated the effect of trauma on astrocyte swelling. Further, trauma significantly increased the Na-K-Cl co-transporter (NKCC) activity in neurons, and that inhibition of NKCC activity diminished the trauma-induced neuronal swelling. Our results indicate that a differential sensitivity to trauma-induced cell swelling exists in neural cells and that neurons and microglia are likely to be involved in the potentiation of the astrocyte swelling post-trauma.

A Meta-Analysis of the Relations Between Three Types of Peer Norms and Adolescent Sexual Behavior.

PubMed

van de Bongardt, Daphne; Reitz, Ellen; Sandfort, Theo; Deković, Maja

2015-08-01

The aim of the present meta-analysis was to investigate the associations between three types of peer norms-descriptive norms (peer sexual behaviors), injunctive norms (peer sexual attitudes), and peer pressure to have sex-and two adolescent sexual behavior outcomes (sexual activity and sexual risk behavior). Adolescent sexual activity was more strongly associated with descriptive norms (ESrfixed=.40) than with injunctive norms (ESrfixed=.22) or peer pressure (ESrfixed=.10). Compared with the sexual activity outcome, the effect size for descriptive norms (peer sexual risk behavior) for sexual risk behavior was smaller (ESrfixed=.11). Age, gender, peer type, and socio-cultural context significantly moderated these associations. Additional analyses of longitudinal studies suggested that selection effects were stronger than socialization effects. These findings offer empirical support for the conceptual distinction between three types of peer norms and hold important implications for theory, research, and intervention strategies. © 2014 by the Society for Personality and Social Psychology, Inc.

The potential for sexual transmission to compromise control of Ebola virus outbreaks.

PubMed

Vinson, John E; Drake, John M; Rohani, Pejman; Park, Andrew W

2016-06-01

Recent evidence suggests that sexual contact may give rise to transmission of Ebola virus long after infection has been cleared from blood. We develop a simple mathematical model that incorporates contact transmission and sexual transmission parametrized from data relating to the 2013-2015 West African Ebola epidemic. The model explores scenarios where contact transmission is reduced following infection events, capturing behaviour change, and quantifies how these actions reducing transmission may be compromised by sexual transmission in terms of increasing likelihood, size and duration of outbreaks. We characterize the extent to which sexual transmission operates in terms of the probability of initial infection resolving to sexual infectiousness and the sexual transmission rate, and relate these parameters to the overall case burden. We find that sexual transmission can have large effects on epidemic dynamics (increasing attack ratios from 25% in scenarios without sexual transmission but with contact-transmission-reducing behaviour, up to 80% in equivalent scenarios with sexual transmission). © 2016 The Author(s).

Poststreptococcal glomerulonephritis (GN)

MedlinePlus

... following: Decreased urine output Rust-colored urine Swelling (edema), general swelling, swelling of the abdomen, swelling of ... A physical examination shows swelling (edema), especially in the face. ... to the heart and lungs with a stethoscope. Blood pressure ...

Energetics, scaling and sexual size dimorphism of spiders.

PubMed

Grossi, B; Canals, M

2015-03-01

The extreme sexual size dimorphism in spiders has motivated studies for many years. In many species the male can be very small relative to the female. There are several hypotheses trying to explain this fact, most of them emphasizing the role of energy in determining spider size. The aim of this paper is to review the role of energy in sexual size dimorphism of spiders, even for those spiders that do not necessarily live in high foliage, using physical and allometric principles. Here we propose that the cost of transport or equivalently energy expenditure and the speed are traits under selection pressure in male spiders, favoring those of smaller size to reduce travel costs. The morphology of the spiders responds to these selective forces depending upon the lifestyle of the spiders. Climbing and bridging spiders must overcome the force of gravity. If bridging allows faster dispersal, small males would have a selective advantage by enjoying more mating opportunities. In wandering spiders with low population density and as a consequence few male-male interactions, high speed and low energy expenditure or cost of transport should be favored by natural selection. Pendulum mechanics show the advantages of long legs in spiders and their relationship with high speed, even in climbing and bridging spiders. Thus small size, compensated by long legs should be the expected morphology for a fast and mobile male spider.

Sexually selected females in the monogamous Western Australian seahorse.

PubMed

Kvarnemo, Charlotta; Moore, Glenn I; Jones, Adam G

2007-02-22

Studies of sexual selection in monogamous species have hitherto focused on sexual selection among males. Here, we provide empirical documentation that sexual selection can also act strongly on females in a natural population with a monogamous mating system. In our field-based genetic study of the monogamous Western Australian seahorse, Hippocampus subelongatus, sexual selection differentials and gradients show that females are under stronger sexual selection than males: mated females are larger than unmated ones, whereas mated and unmated males do not differ in size. In addition, the opportunity for sexual selection (variance in mating success divided by its mean squared) for females is almost three times that for males. These results, which seem to be generated by a combination of a male preference for larger females and a female-biased adult sex ratio, indicate that substantial sexual selection on females is a potentially important but under-appreciated evolutionary phenomenon in monogamous species.

Sexually selected females in the monogamous Western Australian seahorse

PubMed Central

Kvarnemo, Charlotta; Moore, Glenn I; Jones, Adam G

2006-01-01

Studies of sexual selection in monogamous species have hitherto focused on sexual selection among males. Here, we provide empirical documentation that sexual selection can also act strongly on females in a natural population with a monogamous mating system. In our field-based genetic study of the monogamous Western Australian seahorse, Hippocampus subelongatus, sexual selection differentials and gradients show that females are under stronger sexual selection than males: mated females are larger than unmated ones, whereas mated and unmated males do not differ in size. In addition, the opportunity for sexual selection (variance in mating success divided by its mean squared) for females is almost three times that for males. These results, which seem to be generated by a combination of a male preference for larger females and a female-biased adult sex ratio, indicate that substantial sexual selection on females is a potentially important but under-appreciated evolutionary phenomenon in monogamous species. PMID:17476772

The role of ecology, neutral processes and antagonistic coevolution in an apparent sexual arms race.

PubMed

Perry, Jennifer C; Garroway, Colin J; Rowe, Locke

2017-09-01

Some of the strongest examples of a sexual 'arms race' come from observations of correlated evolution in sexually antagonistic traits among populations. However, it remains unclear whether these cases truly represent sexually antagonistic coevolution; alternatively, ecological or neutral processes might also drive correlated evolution. To investigate these alternatives, we evaluated the contributions of intersex genetic correlations, ecological context, neutral genetic divergence and sexual coevolution in the correlated evolution of antagonistic traits among populations of Gerris incognitus water striders. We could not detect intersex genetic correlations for these sexually antagonistic traits. Ecological variation was related to population variation in the key female antagonistic trait (spine length, a defence against males), as well as body size. Nevertheless, population covariation between sexually antagonistic traits remained substantial and significant even after accounting for all of these processes. Our results therefore provide strong evidence for a contemporary sexual arms race. © 2017 John Wiley & Sons Ltd/CNRS.

The effects of sex, ethnicity, and sexual orientation on self-measured digit ratio (2D:4D).

PubMed

Manning, John T; Churchill, Andrew J G; Peters, Michael

2007-04-01

We used self-reported direct finger measurements from 255,116 participants in a BBC Internet survey to investigate the measurement of 2D:4D ratios and their association with sex, ethnicity, and sexual orientation. We found significant sex differences such that males had lower 2D:4D than females and the effect size of the sex differences was greatest for right hand 2D:4D. Mean 2D:4D was lower for right hands than for left hands in men, but lower for left hands compared to right hands in women. The sexual dimorphism in 2D:4D was present across ethnic and country groupings, suggesting that it is universal in humans. However, there was also evidence that mean 2D:4D varied across ethnic groups with higher ratios for Whites, Non-Chinese Asians, and Mid-Easterners and lower ratios in Chinese and Black samples. There were significant differences in 2D:4D across sexual orientation groups but these were confined to men. Male homosexuals and bisexuals had higher mean 2D:4D (suggesting exposure to lower prenatal T) than heterosexuals. The effect was present in Whites, but there was no evidence for the pattern among Black and Chinese participants. In women, there were no significant effects of sexual orientation on 2D:4D. Most studies of sexual orientation effects on 2D:4D have measured finger length from photocopies of the hands. In comparison, our self-reported measures gave higher mean 2D:4D, lower effect sizes, and, in some instances, different patterns of effect size. The implications of our findings for future research into 2D:4D are discussed.

Metric variation and sexual dimorphism in the dentition of Ouranopithecus macedoniensis.

PubMed

Schrein, Caitlin M

2006-04-01

The fossil sample attributed to the late Miocene hominoid taxon Ouranopithecus macedoniensis is characterized by a high degree of dental metric variation. As a result, some researchers support a multiple-species taxonomy for this sample. Other researchers do not think that the sample variation is too great to be accommodated within one species. This study examines variation and sexual dimorphism in mandibular canine and postcanine dental metrics of an Ouranopithecus sample. Bootstrapping (resampling with replacement) of extant hominoid dental metric data is performed to test the hypothesis that the coefficients of variation (CV) and the indices of sexual dimorphism (ISD) of the fossil sample are not significantly different from those of modern great apes. Variation and sexual dimorphism in Ouranopithecus M(1) dimensions were statistically different from those of all extant ape samples; however, most of the dental metrics of Ouranopithecus were neither more variable nor more sexually dimorphic than those of Gorilla and Pongo. Similarly high levels of mandibular molar variation are known to characterize other fossil hominoid species. The Ouranopithecus specimens are morphologically homogeneous and it is probable that all but one specimen included in this study are from a single population. It is unlikely that the sample includes specimens of two sympatric large-bodied hominoid species. For these reasons, a single-species hypothesis is not rejected for the Ouranopithecus macedoniensis material. Correlations between mandibular first molar tooth size dimorphism and body size dimorphism indicate that O. macedoniensis and other extinct hominoids were more sexually size dimorphic than any living great apes, which suggests that social behaviors and life history profiles of these species may have been different from those of living species.

Using the internet to recruit rural MSM for HIV risk assessment: sampling issues.

PubMed

Bowen, Anne; Williams, Mark; Horvath, Keith

2004-09-01

The Internet is an emerging research tool that may be useful for contacting and working with rural men who have sex with men (MSM). Little is known about HIV risks for rural men and Internet methodological issues are only beginning to be examined. Internet versus conventionally recruited samples have shown both similarities and differences in their demographic characteristics. In this study, rural MSM from three sizes of town were recruited by two methods: conventional (e.g. face-to-face/snowball) or Internet. After stratifying for size of city, demographic characteristics of the two groups were similar. Both groups had ready access to the Internet. Patterns of sexual risk were similar across the city sizes but varied by recruitment approach, with the Internet group presenting a somewhat higher HIV sexual risk profile. Overall, these findings suggest the Internet provides a useful and low cost approach to recruiting and assessing HIV sexual risks for rural White MSM. Further research is needed on methods for recruiting rural minority MSM.

Neonatal stimulation of 5-HT(2) receptors reduces androgen receptor expression in the rat anteroventral periventricular nucleus and sexually dimorphic preoptic area.

PubMed

Dakin, C L; Wilson, C A; Kalló, I; Coen, C W; Davies, D C

2008-05-01

Masculinization of the brain is dependent upon a perinatal surge in testosterone. It also requires a transient decrease in hypothalamic 5-HT concentration and turnover and an increase in androgen receptor (AR) expression during the second postnatal week. We have previously shown that increasing 5-HT activity over this period in male or androgenized female rats feminizes their adult behaviour and also feminizes the size of their anteroventral periventricular nucleus (AVPV) and sexually dimorphic nucleus of the preoptic area (SDN-POA). To investigate the role of 5-HT in sexual differentiation of the brain, 5-HT activity was raised over postnatal days 8-16 in male, female and androgenized female rats by daily administration of the 5-HT(2) receptor agonist (-)[2,5 dimethoxy-4-iodophenyl]-2-amino propane hydrochloride [(-)DOI]. By postnatal day 18, the size of the AVPV and SDN-POA was sexually dimorphic; their sizes were feminized by (-)DOI treatment. In the absence of (-)DOI treatment, there were significantly more AR-immunoreactive cells in the AVPV of males, and in the SDN-POA of males and androgenized females, than in those of females on postnatal day 18. (-)DOI treatment reduced the number of AR-immunoreactive cells in the AVPV and SDN-POA of males and androgenized females, but not of females, by postnatal day 18. These results suggest that 5-HT(2) receptor activation can influence sexual differentiation of the brain by controlling AR expression.

Canine tooth size and fitness in male mandrills (Mandrillus sphinx).

PubMed

Leigh, Steven R; Setchell, Joanna M; Charpentier, Marie; Knapp, Leslie A; Wickings, E Jean

2008-07-01

Sexual selection theory explains the evolution of exaggerated male morphologies and weaponry, but the fitness consequences of developmental and age-related changes in these features remain poorly understood. This long-term study of mandrill monkeys (Mandrillus sphinx) demonstrates how age-related changes in canine tooth weaponry and adult canine size correlate closely with male lifetime reproductive success. Combining long-term demographic and morphometric data reveals that male fitness covaries simply and directly with canine ontogeny, adult maximum size, and wear. However, fitness is largely independent of other somatometrics. Male mandrills sire offspring almost exclusively when their canines exceed approximately 30 mm, or two-thirds of average adult value (45 mm). Moreover, sires have larger canines than nonsires. The tooth diminishes through wear as animals age, corresponding with, and perhaps influencing, reproductive senescence. These factors combine to constrain male reproductive opportunities to a brief timespan, defined by the period of maximum canine length. Sexually-selected weaponry, especially when it is nonrenewable like the primate canine tooth, is intimately tied to the male life course. Our analyses of this extremely dimorphic species indicate that sexual selection is closely intertwined with growth, development, and aging, pointing to new directions for sexual selection theory. Moreover, the primate canine tooth has potential as a simple mammalian system for testing genetically-based models of aging. Finally, the tooth may record details of life histories in fossil primates, especially when sexual selection has played a role in the evolution of dimorphism.

The Proximate Causes of Sexual Size Dimorphism in Phrynocephalus przewalskii

PubMed Central

Zhao, Wei; Liu, Nai-fa

2014-01-01

Sexual size dimorphism (SSD) is a common phenomenon and is a central topic in evolutionary biology. Recently, the importance of pursuing an ontogenetic perspective of SSD has been emphasized, to elucidate the proximate physiological mechanisms leading to its evolution. However, such research has seldom focused on the critical periods when males and females diverge. Using mark-recapture data, we investigated the development of SSD, sex-specific survivorship, and growth rates in Phrynocephalus przewalskii (Agamidae). We demonstrated that both male and female lizards are reproductively mature at age 10–11 months (including 5 months hibernation). Male-biased SSD in snout-vent length (SVL) was only found in adults and was fully expressed at age 11 months (June of the first full season of activity), just after sexual maturation. However, male-biased SSD in tail length (TL), hind-limb length (LL), and head width (HW) were fully expressed at age 9–10 months, just before sexual maturation. Analysis of age-specific linear growth rates identified sexually dimorphic growth during the fifth growth month (age 10–11 months) as the proximate cause of SSD in SVL. The males experienced higher mortality than females in the first 2 years and only survived better than females after SSD was well developed. This suggests that the critical period of divergence in the sizes of male and female P. przewalskii occurs between 10 and 11 months of age (May to June during the first full season of activity), and that the sexual difference in growth during this period is the proximate cause. However, the sexual difference in survivorship cannot explain the male-biased SSD in SVL. Our results indicate that performance-related characteristics, such as TL, HW, and LL diverged earlier than SVL. The physiological mechanisms underlying the different growth patterns of males and females may reflect different energy allocations associated with their different reproductive statuses. PMID:24465815

Sexual dimorphism in a dioecious population of the wind-pollinated herb Mercurialis annua: the interactive effects of resource availability and competition.

PubMed

Hesse, Elze; Pannell, John R

2011-05-01

Male-biased sex allocation commonly occurs in wind-pollinated hermaphroditic plants, and is often positively associated with size, notably in terms of height. Currently, it is not well established whether a corresponding pattern holds for dioecious plants: do males of wind-pollinated species exhibit greater reproductive allocation than females? Here, sexual dimorphism is investigated in terms of life history trade-offs in a dioecious population of the wind-pollinated ruderal herb Mercurialis annua. The allocation strategies of males and females grown under different soil nutrient availability and competitive (i.e. no, male or female competitor) regimes were compared. Male reproductive allocation increased disproportionately with biomass, and was greater than that of females when grown in rich soils. Sexual morphs differentially adjusted their reproductive allocation in response to local environmental conditions. In particular, males reduced their reproductive allocation in poor soils, whereas females increased theirs, especially when competing with another female rather than growing alone. Finally, males displayed smaller above-ground vegetative sizes than females, but neither nutrient availability nor competition had a strong independent effect on relative size disparities between the sexes. Selection appears to favour plasticity in reproductive allocation in dioecious M. annua, thereby maintaining a relatively constant size hierarchy between sexual morphs. In common with other dioecious species, there seems to be little divergence in the niches occupied by males and females of M. annua.

Sexual dimorphism in a dioecious population of the wind-pollinated herb Mercurialis annua: the interactive effects of resource availability and competition

PubMed Central

Hesse, Elze; Pannell, John R.

2011-01-01

Background and Aims Male-biased sex allocation commonly occurs in wind-pollinated hermaphroditic plants, and is often positively associated with size, notably in terms of height. Currently, it is not well established whether a corresponding pattern holds for dioecious plants: do males of wind-pollinated species exhibit greater reproductive allocation than females? Here, sexual dimorphism is investigated in terms of life history trade-offs in a dioecious population of the wind-pollinated ruderal herb Mercurialis annua. Methods The allocation strategies of males and females grown under different soil nutrient availability and competitive (i.e. no, male or female competitor) regimes were compared. Key Results Male reproductive allocation increased disproportionately with biomass, and was greater than that of females when grown in rich soils. Sexual morphs differentially adjusted their reproductive allocation in response to local environmental conditions. In particular, males reduced their reproductive allocation in poor soils, whereas females increased theirs, especially when competing with another female rather than growing alone. Finally, males displayed smaller above-ground vegetative sizes than females, but neither nutrient availability nor competition had a strong independent effect on relative size disparities between the sexes. Conclusions Selection appears to favour plasticity in reproductive allocation in dioecious M. annua, thereby maintaining a relatively constant size hierarchy between sexual morphs. In common with other dioecious species, there seems to be little divergence in the niches occupied by males and females of M. annua. PMID:21385775

Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting.

PubMed

O'Dea, Aaron; Shaffer, Marian Lynne; Doughty, Douglas R; Wake, Thomas A; Rodriguez, Felix A

2014-05-07

Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible.

Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting

PubMed Central

O'Dea, Aaron; Shaffer, Marian Lynne; Doughty, Douglas R.; Wake, Thomas A.; Rodriguez, Felix A.

2014-01-01

Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible. PMID:24648229

Effects of the men's program on U.S. Army soldiers' intentions to commit and willingness to intervene to prevent rape: a pretest posttest study.

PubMed

Foubert, John D; Masin, Ryan C

2012-01-01

Noncommissioned male officers in the U.S. Army stationed in Germany were trained to present a 1-hour rape prevention workshop--The Men's Program--to 237 enlisted male soldiers. A comparison group of 244 male soldiers received a briefing focused on reducing the individual's risk for experiencing sexual assault, discussion of myths and facts about sexual assault, and how to avoid being accused of sexual assault. Participants in The Men's Program experienced significant change in the predicted direction for bystander willingness to help, bystander efficacy, rape myth acceptance, likelihood of raping, and likelihood of committing sexual assault with low to medium effect sizes. Comparison group participants experienced no effect on these variables except for a significant decline in rape myth acceptance with a very low effect size. Between-group differences pointed to the efficacy of The Men's Program. Implications of these results for rape prevention programming in the military are discussed.

Barrier properties of heat treated starch Pickering emulsions.

PubMed

Sjöö, Malin; Emek, Sinan Cem; Hall, Tina; Rayner, Marilyn; Wahlgren, Marie

2015-07-15

There is a recognized technological need for delivery systems encapsulating lipophilic substances in food and pharmaceutical products. Pickering emulsions can provide well-defined and highly stable systems, but may not provide good enough barrier properties. Starch granules, recently being used for Pickering stabilization, have the advantage of the ability to swell during gelatinization. Hence, this property could be used to tune and control barrier properties. Oil-in-water Pickering emulsions stabilized by starch were subject to heat treatment at different conditions. The influence of temperature, time, and storage on emulsion drop characteristics was evaluated. In order to further evaluate the barrier properties, lipolysis using the pH-stat method was applied and the effect of starch concentration, treatment temperature, and preliminary oral conditions were also investigated. A better encapsulating barrier was obtained by starch swelling at the oil drop interface. This was seen as reduced lipase activity. The internal oil drop size remained intact and the starch was kept at the interface during heat treatment. The extent of swelling could be controlled by the heating conditions and had impact on the ability to prevent lipase transport through the starch barrier layer. Addition of α-amylase simulating oral digestion only had minor impact on the barrier effect. Copyright © 2015 Elsevier Inc. All rights reserved.

Preparation of poly(MAA-g-EG) hydrogel nanoparticles by a thermally-initiated free radical dispersion polymerization.

PubMed

Deng, Liandong; He, Xiaohua; Li, Aigui; Yang, Qiuxia; Dong, Anjie

2007-02-01

Poly(methacrylic acid-grafted-poly(ethylene glycol)) (P(MAA-g-EG)) hydrogel nanoparticles (HNPs) were prepared by a thermally-initiated free radical dispersion polymerization method. The effects of various reaction parameters on the preparation of HNPs were investigated, including the quantity of monomer, temperature, initiator dosage, crosslinker dosage, and co-stabilizer concentration. The reaction temperature at 75 degrees C was found to be suitable for preparing stable and small P(MAA-g-EG) HNPs. By adding a little amount of polyvinyl alcohol in the reaction media, P(MAA-g-EG) HNPs with narrow size distribution could be obtained. The effects of pH and the crosslinker dosage on the equilibrium swelling behavior of P(MAA-g-EG) HNPs were also studied. The P(MAA-g-EG) HNPs perform pH-responsive swelling behavior, which is strongly influenced by the crosslinker dosage.

Spironolactone-Induced Unilateral Gynecomastia

PubMed Central

Veeregowda, Sahana Hadihalli; Krishnamurthy, Jayakumar Jyothinagaram; Krishnaswamy, Bhuvana; Narayana, Sarala

2018-01-01

Gynecomastia is benign enlargement of male breast, drug-induced gynecomastia accounts for about 25%. We are reporting a case of spironolactone-induced unilateral gynecomastia. A 52-year-old male patient receiving multiple antihypertensives including hydrochlorothiazide presented with muscle weakness and easy fatigability. Investigations revealed hypokalemia; he was advised to stop hydrochlorothiazide and consume potassium-rich diet; since he did not respond to this, spironolactone was added. The patient improved symptomatically but developed painful swelling of the right breast after 12 months of treatment which was suspected to be spironolactone-induced gynecomastia. Within a month of stopping the drug, pain in the right breast subsided followed by decrease in size of swelling. Literature search indicates bilateral gynecomastia by spironolactone, but when clinician encounters unilateral presentation, they should consider the possibility of drug-induced etiology. Patients should be educated about this while prescribing, and eplerenone can be a safe alternative. PMID:29552536

Spironolactone-Induced Unilateral Gynecomastia.

PubMed

Veeregowda, Sahana Hadihalli; Krishnamurthy, Jayakumar Jyothinagaram; Krishnaswamy, Bhuvana; Narayana, Sarala

2018-01-01

Gynecomastia is benign enlargement of male breast, drug-induced gynecomastia accounts for about 25%. We are reporting a case of spironolactone-induced unilateral gynecomastia. A 52-year-old male patient receiving multiple antihypertensives including hydrochlorothiazide presented with muscle weakness and easy fatigability. Investigations revealed hypokalemia; he was advised to stop hydrochlorothiazide and consume potassium-rich diet; since he did not respond to this, spironolactone was added. The patient improved symptomatically but developed painful swelling of the right breast after 12 months of treatment which was suspected to be spironolactone-induced gynecomastia. Within a month of stopping the drug, pain in the right breast subsided followed by decrease in size of swelling. Literature search indicates bilateral gynecomastia by spironolactone, but when clinician encounters unilateral presentation, they should consider the possibility of drug-induced etiology. Patients should be educated about this while prescribing, and eplerenone can be a safe alternative.

Benign Fibrous Histiocytoma: An Uncommon Presentation.

PubMed

Sarkar, Sagarika; Maiti, Moumita; Bhattacharyya, Palas; Sarkar, Ranu

2017-07-01

Intracranial fibrous histiocytomas are rare; Benign Fibrous Histiocytoma (BFH) being uncommon than its malignant counterpart. BFH comprises fibroblasts and histiocytes without any nuclear pleomorphism or atypia. We present a case of a 42-year-old male who had swelling over the occipital region for the past five years, which progressively increased in size. He developed headache, dizziness, and gait disturbance over the last six months. Computed tomographic scan revealed a posterior fossa space-occupying lesion. Fine-needle aspiration cytology from the swelling revealed spindled fibroblasts along with histiocytes and multinucleated giant cells. Later, histopathology showed presence of spindle-shaped cells in storiform pattern admixed with histiocytes and giant cells. The giant cells and histiocytes were immunopositive for CD68 and spindled cells were positive for vimentin, but immunonegative for CD34, epithelial membrane antigen, CD1a and S100. The final diagnosis was intracranial BFH. We present this case because of its extreme rarity and unusual location.

Representin' in cyberspace: sexual scripts, self-definition, and hip hop culture in Black American adolescent girls' home pages.

PubMed

Stokes, Carla E

2007-01-01

Despite the importance of media in the lives of girls, sexuality researchers have largely overlooked how Black American adolescent girls engage with media to construct sexual self-definitions and explore their emerging sexuality. This study investigated sexual scripts, self-definition, and hip hop culture in internet home pages constructed by Black girls aged 14-17 years residing in southern states in the USA. Although some girls in the sample constructed sexual self-representations that mirrored sexual scripts portrayed in the media, hip hop, and youth cyberculture, others resisted stereotypical representations of Black female sexuality. This paper discusses the dominant sexual scripts that emerged from in-depth analysis of 27 home pages constructed by girls residing in Georgia. The focus is on 'Freaks', 'Virgins', 'Down-Ass Chicks/Bitches', 'Pimpettes', and Resisters. Findings suggest that a one-size-fits-all approach to sexuality education may fail to address key contextual issues of relevance to girls and young women. Innovative sexuality and media education strategies that respond to the significance of media in the lives of Black American girls and young women are needed.

Demographics of the spawning aggregations of four catostomid species in the Savannah River, South Carolina and Georgia, USA

USGS Publications Warehouse

Grabowski, T.B.; Ratterman, N.L.; Isely, J.J.

2008-01-01

Differences in the life history strategies employed by otherwise ecologically similar species of a fish assemblage may be an important factor in the coexistence of these species and is an essential consideration in the conservation and management of these assemblages. We collected scales to determine age and growth of four species of the catostomid assemblage (northern hogsucker Hypentelium nigricans, spotted sucker Minytrema melanops, notchlip redhorse Moxostoma collapsum and robust redhorse Moxostoma robustum) of the Savannah River, Georgia-South Carolina in spring 2004 and 2005. Robust redhorse was the largest species; reaching sexual maturity at an older age and growing faster as a juvenile than the other species. Spotted sucker did not achieve the same size as robust redhorse, but reached sexual maturity at younger ages. Notchlip redhorse was intermediate between the abovementioned two species in age at maturity and size. Northern hogsucker was the smallest species of the assemblage and reached the sexual maturity at the age of three. Both robust redhorse and spotted sucker were sexually dimorphic in size-at-age. The range of life history strategies employed by Savannah River catostomids encompasses the range of life history strategies exhibited within the family as a whole. ?? 2007 Blackwell Munksgaard.

The sex lives of parasites: investigating the mating system and mechanisms of sexual selection of the human pathogen Schistosoma mansoni.

PubMed

Steinauer, Michelle L

2009-08-01

The mating systems of internal parasites are inherently difficult to investigate although they have important implications for the evolutionary biology of the species, disease epidemiology, and are important considerations for control measures. Using parentage analyses, three topics concerning the mating biology of Schistosoma mansoni were investigated: the number of mates per adult male and female, variance in reproductive success among individuals, and the potential role for sexual selection on male body size and also mate choice for genetically dissimilar individuals. Results indicated that schistosomes were mostly monogamous, and evidence of only one mate change occurred over a period of 5-6 weeks. One male was polygynous and contained two females in its gynecophoral canal although offspring were only detected for one of the females. Even though they were primarily monogamous and the sex ratio near even, reproductive success was highly variable, indicating a potential role for sexual selection. Male body size was positively related to reproductive success, consistent with sexual selection via male-male competition and female choice for large males. However, relatedness of pairs was not associated with their reproductive success. Finally, genetically identical individuals differed significantly in their reproductive output and identical males in their body size, indicating important partner and environmental effects on these traits.

Sexual Violence Inside Prisons: Rates of Victimization

PubMed Central

Blitz, Cynthia L.; Shi, Jing; Bachman, Ronet; Siegel, Jane A.

2006-01-01

People in prison are exposed to and experience sexual violence inside prisons, further exposing them to communicable diseases and trauma. The consequences of sexual violence follow the individual into the community upon release. This paper estimates the prevalence of sexual victimization within a state prison system. A total of 6,964 men and 564 women participated in a survey administered using audio-CASI. Weighted estimates of prevalence were constructed by gender and facility size. Rates of sexual victimization varied significantly by gender, age, perpetrator, question wording, and facility. Rates of inmate-on-inmate sexual victimization in the previous 6 months were highest for female inmates (212 per 1,000), more than four times higher than male rates (43 per 1,000). Abusive sexual conduct was more likely between inmates and between staff and inmates than nonconsensual sexual acts. Sexual violence inside prison is an urgent public health issue needing targeted interventions to prevent and ameliorate its health and social consequences, which spatially concentrate in poor inner-city areas where these individuals ultimately return. PMID:16937087

Effects of plant sex on range distributions and allocation to reproduction.

PubMed

Johnson, Marc T J; Smith, Stacey D; Rausher, Mark D

2010-05-01

Despite an abundance of theory, few empirical studies have explored the ecological and evolutionary consequences of sex. We used a comparative phylogenetic approach to examine whether transitions between sexual and asexual reproduction are associated with changes in the size and distribution of species' geographical ranges, and their investment in reproduction. Here, we reconstructed the phylogeny of the genus Oenothera sections Oenothera and Calylophus (Onagraceae), which contain 35 sexual and 30 functionally asexual species. From each species, we collected data on the geographical distribution and variation in plant traits related to reproduction. Functionally asexual species occurred at higher latitudes, but did not differ in range size, compared with sexual species. Transitions to asexuality were associated with decreased investment in floral structures, including the length of petals, floral tubes and styles. Decreased anther size and increased seed size within asexual species also suggest altered allocation to male and female fitness. The observed range shifts are consistent with superior colonization of environments by asexual species following glaciation, and the observed changes in reproductive allocation support predictions made by models relating to the evolution of selfing. Our results suggest that the evolutionary consequences of asexual reproduction might be less restrictive than previously thought.

Interpopulation Comparison of Sex-Biased Mortality and Sexual Size Dimorphism in Sea-Run Masu Salmon, Oncorhynchus masou.

PubMed

Tamate, Tsuyoshi

2015-08-01

Evolutionary ecologists often expect that natural and sexual selection result in systematic co-occurrence patterns of sex-biased mortality and sexual size dimorphism (SSD) within animal species. However, whether such patterns actually occur in wild animals is poorly examined. The following expectation, the larger sex suffers higher mortality, was primarily tested here for apparently native sea-run masu salmon (Oncorhynchus masou) in three populations in Hokkaido, Japan. Field surveys on sex ratios, body sizes, and ages of smolts and returning adults revealed that two of the three populations exhibited an expected pattern, a female-biased marine mortality and SSD, but one population demonstrated an unexpected co-occurrence of male-biased marine mortality and female-biased SSD. These female-biased SSDs were attributed to faster marine growth of females because of no sex difference in smolt body size. It has been previously suggested that breeding selection favoring large size generally act more strongly in females than in males in Japanese anadromous masu, as there is a weak sexual selection on adult males but universally intensive natural selection on adult females. Thus, this hypothesis explains female-biased SSDs well in all study populations. Interpopulation variation in sex-biased mortality found here might result from differences in marine predation and/or fishing pressures, given that selection driving female-biased SSD makes females forage more aggressively than males during the marine phase. Taken together, these results raise the possibility that evolutionary forces have shaped adaptive sex-specific foraging strategies under relationships between growth and mortality, resulting in co-occurrence patterns of sex-biased mortality and SSD within animal species.

cloncase: Estimation of sex frequency and effective population size by clonemate resampling in partially clonal organisms.

PubMed

Ali, Sajid; Soubeyrand, Samuel; Gladieux, Pierre; Giraud, Tatiana; Leconte, Marc; Gautier, Angélique; Mboup, Mamadou; Chen, Wanquan; de Vallavieille-Pope, Claude; Enjalbert, Jérôme

2016-07-01

Inferring reproductive and demographic parameters of populations is crucial to our understanding of species ecology and evolutionary potential but can be challenging, especially in partially clonal organisms. Here, we describe a new and accurate method, cloncase, for estimating both the rate of sexual vs. asexual reproduction and the effective population size, based on the frequency of clonemate resampling across generations. Simulations showed that our method provides reliable estimates of sex frequency and effective population size for a wide range of parameters. The cloncase method was applied to Puccinia striiformis f.sp. tritici, a fungal pathogen causing stripe/yellow rust, an important wheat disease. This fungus is highly clonal in Europe but has been suggested to recombine in Asia. Using two temporally spaced samples of P. striiformis f.sp. tritici in China, the estimated sex frequency was 75% (i.e. three-quarter of individuals being sexually derived during the yearly sexual cycle), indicating strong contribution of sexual reproduction to the life cycle of the pathogen in this area. The inferred effective population size of this partially clonal organism (Nc  = 998) was in good agreement with estimates obtained using methods based on temporal variations in allelic frequencies. The cloncase estimator presented herein is the first method allowing accurate inference of both sex frequency and effective population size from population data without knowledge of recombination or mutation rates. cloncase can be applied to population genetic data from any organism with cyclical parthenogenesis and should in particular be very useful for improving our understanding of pest and microbial population biology. © 2016 John Wiley & Sons Ltd.

Sexual orientation in males and the evolution of anisogamy.

PubMed

Reed, Lawrence Ian

2010-02-01

How might homosexual orientation have evolved and been maintained? Several adaptationist explanations have been examined in attempt to reconcile the presence of same-sex sexual behaviors with traditional selection-based theory, showing little empirical support. The current paper presents a novel adaptationist explanation for the evolution and maintenance of same-sex sexual behaviors in males, both between- and within-species, related to the evolution of anisogamy. Under conditions of isogamy, sexual reproduction occurs between individuals with gametes of similar morphology. With the evolution of anisogamy came greater specificity on the types of individuals that would produce offspring when mated with (i.e. those with opposing gamete sizes). It is suggested that with this evolutionary change, a specified psychological adaptation orienting individuals primarily towards mating partners with newly opposing gamete sizes was then selected for. It is thus hypothesized that sexual orientation will vary along the anisogamy-isogamy continuum, with homosexual orientation being associated with closer approximations towards isogamy. This hypothesis leads to two specific predictions. First, in comparisons between species, the presence of same-sex sexual behaviors will be more likely to occur as sperm to egg ratios approach 1:1. Second, in comparisons within species, those individuals with greater sperm lengths will be more likely to exhibit same-sex sexual behaviors than those with lesser sperm lengths. Examination of the present hypothesis stands to greatly increase our knowledge of the selective forces shaping both biological and psychological evolution.

Does life history shape sexual size dimorphism in anurans? A comparative analysis

PubMed Central

2013-01-01

Background The evolution of sexual size dimorphism (SSD) is likely constrained by life history. Using phylogenetic comparative methods, we examined correlations between SSD among anurans and their life history traits, including egg size, clutch size, mating combat, and parental care behaviour. We used sexual dimorphism index (SDI = Body-sizefemale /Body-sizemale –1) as the measurement for SSD. Body size, life history and phylogenetic data were collected from published literature. Data were analysed at two levels: all anuran species and within individual families. Results Female-biased SSD is the predominant form in anurans. SSD decreases along with the body size increase, following the prediction of Rensch’s rule, but the magnitude of decrease is very small. More importantly, female body size is positively correlated with both fecundity related traits, egg size and clutch size, and SDI is also positively correlated with clutch size, suggesting fecundity advantage may have driven the evolution of female body size and consequently leads to the evolution of female-biased SSD. Furthermore, the presence of parental care, male parental care in particular, is negatively correlated with SDI, indicating that species with parental care tend to have a smaller SDI. A negative correlation between clutch size and parental care further suggests that parental care likely reduces the fecundity selection pressure on female body size. On the other hand, there is a general lack of significant correlation between SDI and the presence of male combat behaviour, which is surprising and contradictory to previous studies. Conclusions We find clear evidence to support the ‘fecundity advantage hypothesis’ and the ‘parental care hypothesis’ in shaping SSD in anurans. Nevertheless, the relationships of both parental care and combat behaviour to the evolution of SSD are complex in anurans and the extreme diversity of life history traits may have masked some potential interesting relationships. Our study represents the most comprehensive study of SSD in anurans to date. PMID:23368708

[Inaccurate information about the size of the penis in the Democratic Republic of the Congo: about 21 information sources].

PubMed

Mulenga, Philippe Cilundika; Kazadi, Alex Bukasa

2016-01-01

Penis size is a huge topic of anxiety for a lot of men. Some of them are unhappy with their penis size as shown in the study conducted by Tiggemann in 2008. There are relatively few studies on erect penis size. This may reflect cultural taboos of researchers or doctors interacting with men who are in a state of sexual arousal. On the other hand, it is important for people who announce details on penis size to give the average penis size first and then sizes suggested by the researchers. We performed a cross-sectional survey in the two major urban centres of the Democratic Republic of Congo namely Kinshasa and Lubumbashi over a period of two years from May 2014 to May 2016. A total of 21 information sources constituted our sample, 8 in Kinshasa and 13 in Lubumbashi. We found it sufficient because in our culture discussing about sexual matter is rare. The parameters studied were: the nature of the source, the accuracy of the measurement method, the presence of bibliographical reference, the announced penis size. The majority of information sources used were radio or television broadcastings (23,8%); this can be explained by the fact that there are an increasing number of radio and television stations in our country and especially in large cities. With regard to accuracy of information about penis measurement method when sharing the message about penis size, our study showed that the majority of information sources did not indicate it when they announced penis size to the public (85,7%). Several sources did not report bibliographical references (57,1%). Announced data analysis on penis size showed that the average penis size was: 14 cm (28,6%), 15 cm (23,8%) and 15-20 cm (19%). All these results are intended to offer a warning to all players responsible for diffusing information on sexual health (penis size): scientific rigor consists in seeking information from reliable sources.

The effect of sexual health education program on women sexual function in Iran.

PubMed

Behboodi Moghadam, Zahra; Rezaei, Elham; Khaleghi Yalegonbadi, Fariba; Montazeri, Ali; Arzaqi, Syed Masood; Tavakol, Zeinab; Yari, Fatemeh

2015-01-01

Sexual dysfunction is the most common disorder in women. According to the WHO, sexual education programs are considered as a need. Therefore, this study was designed to investigate the effect of educational program on sexual function in women with sexual dysfunction. This randomized trial, was conducted in 2013 on 90 married women by convenient sampling in Qazvin, central Iran. The demographic, Female Sexual Function Index (FSFI), and Beck's Depression Inventory (BDI) questionnaires were completed during structured interviews. After completing the sample size, subjects were divided randomly into two groups by using the table of random numbers (educational and control groups), then respectively received an educational intervention in the four sessions with one week interval and routine program offered by the center and following-up was done with refilling questionnaires 8 weeks after intervention. Sexual function improved after sex educational programs in all dimensions (sexual desire (P=0.006), sexual exciting (P=0.006), vaginal moisture (P=0.002), sexual satisfaction (P=0.011), and total score of sexual function (P=0.001). Considering the importance role of sexual function in family strength, health, and development, it can be claimed that educational sex programs can help practitioners to improve sexual function of married women with sexual dysfunction.

Housing and management factors associated with indicators of dairy cattle welfare.

PubMed

de Vries, M; Bokkers, E A M; van Reenen, C G; Engel, B; van Schaik, G; Dijkstra, T; de Boer, I J M

2015-01-01

Knowledge of potential synergies and trade-offs between housing and management factors for different aspects of animal welfare is essential for farmers who aim to improve the level of welfare in their herds. The aim of this research was to identify and compare housing and management factors associated with prevalence of lameness, prevalence of lesions or swellings, prevalence of dirty hindquarters, and frequency of displacements (social behavior) in dairy herds in free-stall housing. Seven observers collected data regarding housing and management characteristics of 179 Dutch dairy herds (herd size: 22-211 cows) in free-stall housing during winter. Lame cows, cows with lesions or swellings, and cows with dirty hindquarters were counted and occurrence of displacements was recorded during 120 min of observation. For each of the four welfare indicators, housing and management factors associated with the welfare indicator were selected in a succession of logistic or log-linear regression analyses. Prevalence of lameness was associated with surface of the lying area, summer pasturing, herd biosecurity status, and far-off and close-up dry cow groups (P<0.05). Prevalence of lesions or swellings was associated with surface of the lying area, summer pasturing, light intensity in the barn, and days in milk when the maximum amount of concentrates was fed (P<0.05). Prevalence of dirty hindquarters was associated with surface of the lying area, proportion of stalls with fecal contamination, head lunge impediments in stalls, and number of roughage types (P<0.05). Average frequency of displacements was associated with the time of introducing heifers in the lactating group, the use of cow brushes, continuous availability of roughage, floor scraping frequency, herd size, and the proportion cows to stalls (P<0.05). Prevalences of lameness and of lesions or swellings were lower in herds with soft mats or mattresses (odd ratio (OR)=0.66 and 0.58, confidence interval (CI)=0.48-0.91 and 0.39-0.85) or deep bedding (OR=0.48 and 0.48, CI=0.32-0.71 and 0.30-0.77) in stalls, compared with concrete, and in herds with summer pasturing (OR=0.68 and 0.41, CI=0.51-0.90 and 0.27-0.61), compared with zero-grazing. Deep bedding in stalls was negatively associated with prevalence of dirty hindquarters (OR=0.50, CI=0.29-0.86), compared with hard mats. It was concluded that some aspects of housing and management are common protective factors for prevalence of lameness, lesions or swellings, and dirty hindquarters, but not for frequency of displacements. Copyright © 2014 Elsevier B.V. All rights reserved.

The relationship between sexual abuse and risky sexual behavior among adolescent boys: a meta-analysis.

PubMed

Homma, Yuko; Wang, Naren; Saewyc, Elizabeth; Kishor, Nand

2012-07-01

Childhood and adolescent sexual abuse has been shown to lead to increased odds of sexual behaviors that lead to sexually transmitted infections and early pregnancy involvement. Research, meta-analyses, and interventions, however, have focused primarily on girls and young women who have experienced abuse, yet some adolescent boys are also sexually abused. We performed a meta-analysis of the existing studies to assess the magnitudes of the link between a history of sexual abuse and each of the three risky sexual behaviors among adolescent boys in North America. The three outcomes were (a) unprotected sexual intercourse, (b) multiple sexual partners, and (c) pregnancy involvement. Weighted mean effect sizes were computed from ten independent samples, from nine studies published between 1990 and 2011. Sexually abused boys were significantly more likely than nonabused boys to report all three risky sexual behaviors. Weighted mean odds ratios were 1.91 for unprotected intercourse, 2.91 for multiple sexual partners, and 4.81 for pregnancy involvement. Our results indicate that childhood and adolescent sexual abuse can substantially influence sexual behavior in adolescence among male survivors. To improve sexual health for all adolescents, even young men, we should strengthen sexual abuse prevention initiatives, raise awareness about male sexual abuse survivors' existence and sexual health issues, improve sexual health promotion for abused young men, and screen all people, regardless of gender, for a history of sexual abuse. Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

The Relationship Between Sexual Abuse and Risky Sexual Behavior Among Adolescent Boys: A Meta-Analysis

PubMed Central

Homma, Yuko; Wang, Naren; Saewyc, Elizabeth; Kishor, Nand

2016-01-01

Purpose Childhood and adolescent sexual abuse has been shown to lead to increased odds of sexual behaviors that lead to sexually transmitted infections and early pregnancy involvement. Research, meta-analyses, and interventions, however, have focused primarily on girls and young women who have experienced abuse, yet some adolescent boys are also sexually abused. We performed a meta-analysis of the existing studies to assess the magnitudes of the link between a history of sexual abuse and each of three risky sexual behaviors among adolescent boys in North America. Methods The three outcomes were a) unprotected sexual intercourse, b) multiple sexual partners, and c) pregnancy involvement. Weighted mean effect sizes were computed from 10 independent samples, from nine studies published between 1990 and 2011. Results Sexually abused boys were significantly more likely than non-abused boys to report all three risky sexual behaviors. Weighted mean odds ratios were 1.91 for unprotected intercourse, 2.91 for multiple sexual partners, and 4.81 for pregnancy involvement. Conclusions Our results indicate that childhood and adolescent sexual abuse can substantially Influence sexual behavior in adolescence among male survivors. To improve sexual health for all adolescents, even young men, we should strengthen sexual abuse prevention initiatives, raise awareness about male sexual abuse survivors’ existence and sexual health issues, improve sexual health promotion for abused young men, and screen all people, regardless of gender, for a history of sexual abuse. PMID:22727072

Women's Preferences for Penis Size: A New Research Method Using Selection among 3D Models

PubMed Central

Park, Jaymie; Leung, Shannon

2015-01-01

Women’s preferences for penis size may affect men’s comfort with their own bodies and may have implications for sexual health. Studies of women’s penis size preferences typically have relied on their abstract ratings or selecting amongst 2D, flaccid images. This study used haptic stimuli to allow assessment of women’s size recall accuracy for the first time, as well as examine their preferences for erect penis sizes in different relationship contexts. Women (N = 75) selected amongst 33, 3D models. Women recalled model size accurately using this method, although they made more errors with respect to penis length than circumference. Women preferred a penis of slightly larger circumference and length for one-time (length = 6.4 inches/16.3 cm, circumference = 5.0 inches/12.7 cm) versus long-term (length = 6.3 inches/16.0 cm, circumference = 4.8 inches/12.2 cm) sexual partners. These first estimates of erect penis size preferences using 3D models suggest women accurately recall size and prefer penises only slightly larger than average. PMID:26332467

Women's Preferences for Penis Size: A New Research Method Using Selection among 3D Models.

PubMed

Prause, Nicole; Park, Jaymie; Leung, Shannon; Miller, Geoffrey

2015-01-01

Women's preferences for penis size may affect men's comfort with their own bodies and may have implications for sexual health. Studies of women's penis size preferences typically have relied on their abstract ratings or selecting amongst 2D, flaccid images. This study used haptic stimuli to allow assessment of women's size recall accuracy for the first time, as well as examine their preferences for erect penis sizes in different relationship contexts. Women (N = 75) selected amongst 33, 3D models. Women recalled model size accurately using this method, although they made more errors with respect to penis length than circumference. Women preferred a penis of slightly larger circumference and length for one-time (length = 6.4 inches/16.3 cm, circumference = 5.0 inches/12.7 cm) versus long-term (length = 6.3 inches/16.0 cm, circumference = 4.8 inches/12.2 cm) sexual partners. These first estimates of erect penis size preferences using 3D models suggest women accurately recall size and prefer penises only slightly larger than average.

Potential environmental influences on variation in body size and sexual size dimorphism among Arizona populations of the western diamond-backed rattlesnake (Crotalus atrox)

USGS Publications Warehouse

Amarello, Melissa; Nowak, Erica M.; Taylor, Emily N.; Schuett, Gordon W.; Repp, Roger A.; Rosen, Philip C.; Hardy, David L.

2010-01-01

Differences in resource availability and quality along environmental gradients are important influences contributing to intraspecific variation in body size, which influences numerous life-history traits. Here, we examined variation in body size and sexual size dimorphism (SSD) in relation to temperature, seasonality, and precipitation among 10 populations located throughout Arizona of the western diamond-backed rattlesnake (Crotalus atrox). Specifically, in our analyses we addressed the following questions: (i) Are adult males larger in cooler, wetter areas? (ii) Does female body size respond differently to environmental variation? (iii) Is seasonality a better predictor of body size variation? (iv) Is SSD positively correlated with increased resources? We demonstrate that male and female C. atrox are larger in body size in cooler (i.e., lower average annual maximum, minimum, and mean temperature) and wetter areas (i.e., higher average annual precipitation, more variable precipitation, and available surface water). Although SSD in C. atrox appeared to be more pronounced in cooler, wetter areas, this relationship did not achieve statistical significance.

Size-dependent selective mechanisms on males and females and the evolution of sexual size dimorphism in frogs.

PubMed

Nali, Renato C; Zamudio, Kelly R; Haddad, Célio F B; Prado, Cynthia P A

2014-12-01

Sexual size dimorphism (SSD) varies in animals from male biased to female biased. The evolution of SSD is potentially influenced by a number of factors, such as territoriality, fecundity, and temporal breeding patterns (explosive vs. prolonged). In general, frogs show female-biased SSD with broad variance among species. Using comparative methods, we examine how different selective forces affect male and female sizes, and we test hypotheses about size-dependent mechanisms shaping SSD in frogs. Male size was weakly associated with SSD in all size classes, and we found no significant association among SSD, male size, temporal breeding pattern, and male territoriality. In contrast, female size best explained SSD variation across all size classes but especially for small-bodied species. We found a stronger evolutionary association between female body size and fecundity, and this fecundity advantage was highest in explosively breeding species. Our data indicate that the fecundity advantage associated with female body size may not be linear, such that intermediate and large females benefit less with body size increases. Therefore, size-dependent selection in females associated with fecundity and breeding patterns is an important mechanism driving SSD evolution in frogs. Our study underscores the fact that lineage-specific ecology and behavior should be incorporated in comparative analyses of animal SSD.

A descriptive study of sexual homicide in Canada: implications for police investigation.

PubMed

Beauregard, Eric; Martineau, Melissa

2013-12-01

Few empirical studies have been conducted that examine the phenomenon of sexual homicide, and among these studies, many have been limited by small sample size. Although interesting and informative, these studies may not be representative of the greater phenomenon of sexual murder and may be subject to sampling bias that could have significant effects on results. The current study aims to provide a descriptive analysis of the largest sample of sexual homicide cases across Canada in the past 62 years. In doing so, the study aims to examine offender and victim characteristics, victim targeting and access, and modus operandi. Findings show that cases of sexual homicide and sexual murderers included in the current study differ in many aspects from the portrait of the sexual murderer and his or her crime depicted in previous studies. The authors' results may prove useful to the police officers responsible for the investigation of these crimes.

Validation and Parameter Sensitivity Tests for Reconstructing Swell Field Based on an Ensemble Kalman Filter

PubMed Central

Wang, Xuan; Tandeo, Pierre; Fablet, Ronan; Husson, Romain; Guan, Lei; Chen, Ge

2016-01-01

The swell propagation model built on geometric optics is known to work well when simulating radiated swells from a far located storm. Based on this simple approximation, satellites have acquired plenty of large samples on basin-traversing swells induced by fierce storms situated in mid-latitudes. How to routinely reconstruct swell fields with these irregularly sampled observations from space via known swell propagation principle requires more examination. In this study, we apply 3-h interval pseudo SAR observations in the ensemble Kalman filter (EnKF) to reconstruct a swell field in ocean basin, and compare it with buoy swell partitions and polynomial regression results. As validated against in situ measurements, EnKF works well in terms of spatial–temporal consistency in far-field swell propagation scenarios. Using this framework, we further address the influence of EnKF parameters, and perform a sensitivity analysis to evaluate estimations made under different sets of parameters. Such analysis is of key interest with respect to future multiple-source routinely recorded swell field data. Satellite-derived swell data can serve as a valuable complementary dataset to in situ or wave re-analysis datasets. PMID:27898005

Stability of a very coarse-grained beach at Carmel, California

USGS Publications Warehouse

Dingler, J.R.

1981-01-01

Monastery Beach at Carmel, California, is a pocket beach composed of very coarse to granular sediment. In profile, the beach has a well-defined berm crest; a steep foreshore; and a gently sloping, barless offshore covered by large, long-crested oscillation ripples. Carmel Submarine Canyon heads a few hundred meters offshore of the beach, and San Jose Creek, a small ephemeral steam, ponds onshore of the central part of the berm. Wave conditions vary greatly during a year because the beach lies open to the Pacific Ocean for azimuths between 270??-322??N whence come a variety of wave types. Even with a variable wave climate, Monastery Beach has maintained a swell profile for almost three years. Aperiodic beach surveys show that the beach responds little to seasonal changes in wave climate. Four survey lines maintained the same swell profile throughout the study period. The fifth line maintained a stable profile only across the foreshore; the berm was twice artificially breached during storms to prevent upstream flooding along San Jose Creek. In comparison, Carmel Beach, a nearby beach composed of medium sand, commonly alternates between swell and storm profiles. The increased stability of Monastery Beach relative to Carmel Beach is attributed to two factors: grain size differences and location within Carmel Bay. Rebuilding proceeded very slowly along the breached part of the berm at Monastery Beach. The probable cause of such a low recovery rate is that oscillation ripples trapped the sand that was carried offshore when San Jose Creek eroded the beach. The ripples, which are active under high-energy conditions, approach dormancy under low-energy conditions. Each ripple, therefore, acts like a reservoir, retaining sand during most swell conditions. ?? 1981.

1-Butanol absorption in poly(styrene-divinylbenzene) ion exchange resins for catalysis.

PubMed

Pérez-Maciá, M A; Curcó, D; Bringué, R; Iborra, M; Rodríguez-Ropero, F; van der Vegt, N F A; Aleman, Carlos

2015-12-21

The swelling behaviour of poly(styrene-co-divinylbenzene), P(S-DVB), ion exchange resins in 1-butanol (BuOH) has been studied by means of atomistic classical molecular dynamics simulations (MD). The topological characteristics reported for the resin in the dry state, which exhibited complex internal loops (macropores), were considered for the starting models used to examine the swelling induced by BuOH contents ranging from 10% to 50% w/w. Experimental measurements using a laser diffraction particle size analyzer indicate that swelling causes a volume variation with respect to the dry resin of 21%. According to MD simulations, such a volume increment corresponds to a BuOH absorption of 31-32% w/w, which is in excellent agreement with the indirect experimental estimation (i.e. 31% w/w). Simulations reveal that, independently of the content of BuOH, the density of the swelled resin is higher than that of the dry resin, evidencing that the alcohol provokes important structural changes in the polymeric matrix. Thus, BuOH molecules cause a collapse of the resin macropores when the content of alcohol is ≤20% w/w. In contrast, when the concentration of BuOH is close to the experimental value (∼30% w/w), P(S-DVB) chains remain separated by pores faciliting the access of the reactants to the reaction centers. On the other hand, evaluation of both bonding and non-bonding interactions indicates that the mixing energy is the most important contribution to the absorption of BuOH into the P(S-DVB) resin. Overall, the results displayed in this work represent a starting point for the theoretical study of the catalytic conversion of BuOH into di-n-butyl ether in P(S-DVB) ion exchange resins using sophisticated electronic methods.

Effect of Manual Lymphatic Drainage After Total Knee Arthroplasty: A Randomized Controlled Trial.

PubMed

Pichonnaz, Claude; Bassin, Jean-Philippe; Lécureux, Estelle; Christe, Guillaume; Currat, Damien; Aminian, Kamiar; Jolles, Brigitte M

2016-05-01

To evaluate the effects of manual lymphatic drainage (MLD) on knee swelling and the assumed consequences of swelling after total knee arthroplasty (TKA). Randomized controlled trial. Primary care hospital. Two groups of 30 patients were randomized before TKA surgery (N=60; 65% women [39]; mean age, 70.7±8.8y; weight, 77.8±11.3kg; size, 1.64±0.08m; body mass index, 29.9±4.1kg/m(2)). Participants received either 5 MLD treatments or a placebo, added to rehabilitation, in between the second day and the seventh day after surgery. Swelling was measured by blinded evaluators before surgery and at second day, seventh day, and 3 months using bioimpedance spectroscopy and volume measurement. Secondary outcomes were active and passive range of motion, pain, knee function, and gait parameters. At seventh day and 3 months, no outcome was significantly different between groups, except for the knee passive flexion contracture at 3 months, which was lower and less frequent in the MLD group (-2.6°; 95% confidence interval, -5.0° to -0.21°; P=.04; absolute risk reduction, 26.6%; 95% confidence interval, 0.9%-52.3%; number needed to treat, 4). The mean pain level decreased between 5.8 and 8.2mm on the visual analog scale immediately after MLD, which was significant after 4 of 5 MLD treatments. MLD treatments applied immediately after TKA surgery did not reduce swelling. It reduced pain immediately after the treatment. Further studies should investigate whether the positive effect of MLD on knee extension is replicable. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Extreme sexual behavior in dementia as a specific manifestation of disinhibition.

PubMed

Bartelet, Marjukka; Waterink, Wim; van Hooren, Susan

2014-01-01

In nursing homes, extreme sexual behavior is one of the most challenging behaviors in dementia. Despite this, however, there is no conformity in the literature regarding how to label and define this type of behavior. Examples of labels used include inappropriate sexual behavior, improper sexual behavior, sexually disinhibited behavior, or hyper sexuality. According to recent theoretical perspectives, extreme sexual behavior may be regarded as a part of disinhibited behavior or could be considered as an independent neuropsychiatric symptom. In this multicenter study, it was investigated whether there is a relationship between extreme sexual behavior and the typical neuropsychiatric symptoms seen in dementia. In 179 residents diagnosed with dementia, extreme sexual behavior was measured using an observation scale. Twelve neuropsychiatric symptoms were measured by the Neuropsychiatric Inventory. Multivariate analysis of covariance with gender showed that residents with observed extreme sexual behavior (n = 43) only showed a higher score on neuropsychiatric symptom 'disinhibition', as compared to residents with non-observed sexual behavior (n = 136). In addition, the effect size was large. These findings indicate that among residents with dementia, extreme sexual behaviors should not be considered as an independent neuropsychiatric symptom. Instead, disinhibition may be an important underlying mechanism for extreme sexual behavior and thus validates the label 'sexually disinhibited behavior'.

Video imaging analysis of the plasma membrane permeabilizing effects of Bacillus thuringiensis insecticidal toxins in Sf9 cells.

PubMed

Villalon, M; Vachon, V; Brousseau, R; Schwartz, J L; Laprade, R

1998-01-05

The size and ionic selectivity of the pores formed by the insecticidal crystal protein Cry1C from Bacillus thuringiensis in the plasma membrane of Sf9 cells, an established cell line derived from the fall armyworm Spodoptera frugiperda, were analyzed with a video imaging technique. Changes in the permeability of the membrane were estimated from the rate of osmotic swelling of the cells. In the presence of Cry1C, which is toxic to Sf9 cells, the permeability of the cell membrane to KCl and glucose increased in a dose-dependent manner. In contrast, Cry1Aa, Cry1Ab and Cry1Ac, toxins to which Sf9 cells are not susceptible, had no detectable effect. Pores formed by Cry1C allowed the diffusion of sucrose, but were impermeable to the trisaccharide raffinose. On the basis of the hydrodynamic radii of these substances, the diameter of the pores was estimated to be 1.0-1.2 nm. In the presence of salts, the rate of swelling of cells exposed to Cry1C was about equally influenced by the size of the anion as by that of the cation, indicating that the ionic selectivity of the pores is low.

Investigation on properties of P((MAA-co-DMAEMA)-g-EG) polyampholyte nanogels

NASA Astrophysics Data System (ADS)

Deng, Liandong; Zhai, Yinglei; Guo, Shutao; Jin, Fengmin; Xie, Zhaopeng; He, Xiaohua; Dong, Anjie

2009-02-01

P((MAA-co-DMAEMA)-g-EG) polyampholyte nanogels (PANGs) were prepared by distillation-dispersion copolymerization of poly(ethylene glycol) methyl ether methacrylate (MPEGMA), N, N-dimethylaminoethyl methacrylate (DMAEMA), and methacrylic acid (MAA) using acetonitrile (AN) as dispersion medium. The results of FTIR spectra indicate that the composition of P((MAA-co-DMAEMA)-g-EG) PANGs is consistent with the designed structure. The results of TEM and laser particle size analyzer (LPSA) show that P((MAA-co-DMAEMA)-g-EG) PANGs present spherical morphology and a bimodal size distribution after and before swelling. P((MAA-co-DMAEMA)-g-EG) PANGs have typically amphoteric characters responding to pH, whose isoelectric point (IEP) increases with decreasing the ratio of MAA/DMAEMA and equilibrium swelling degree (ESD) is greater than that at IEP when the pH value is distant from IEP. P((MAA-co-DMAEMA)-g-EG) PANGs also represent ionic strength sensitivity. Using the water-soluble chitosan (CS, Mn = 5 kDa) as model drug, in vitro release indicates that CS can be effectively incorporated into PANGs and the release rate of CS at pH 1.89 is an order of magnitude greater than that at pH 8.36. P((MAA-co-DMAEMA)-g-EG) PANGs may be useful in biomedicine, especially in oral drug delivery of biomacromolecule.

Climate change and sexual size dimorphism in an Arctic spider

PubMed Central

Høye, Toke Thomas; Hammel, Jörg U.; Fuchs, Thomas; Toft, Søren

2009-01-01

Climate change is advancing the onset of the growing season and this is happening at a particularly fast rate in the High Arctic. However, in most species the relative fitness implications for males and females remain elusive. Here, we present data on 10 successive cohorts of the wolf spider Pardosa glacialis from Zackenberg in High-Arctic, northeast Greenland. We found marked inter-annual variation in adult body size (carapace width) and this variation was greater in females than in males. Earlier snowmelt during both years of its biennial maturation resulted in larger adult body sizes and a skew towards positive sexual size dimorphism (females bigger than males). These results illustrate the pervasive influence of climate on key life-history traits and indicate that male and female responses to climate should be investigated separately whenever possible. PMID:19435831

Selection on bristle length has the ability to drive the evolution of male abdominal appendages in the sepsid fly Themira biloba.

PubMed

Herath, B; Dochtermann, N A; Johnson, J I; Leonard, Z; Bowsher, J H

2015-12-01

Many exaggerated and novel traits are strongly influenced by sexual selection. Although sexual selection is a powerful evolutionary force, underlying genetic interactions can constrain evolutionary outcomes. The relative strength of selection vs. constraint has been a matter of debate for the evolution of male abdominal appendages in sepsid flies. These abdominal appendages are involved in courtship and mating, but their function has not been directly tested. We performed mate choice experiments to determine whether sexual selection acts on abdominal appendages in the sepsid Themira biloba. We tested whether appendage bristle length influenced successful insemination by surgically trimming the bristles. Females paired with males that had shortened bristles laid only unfertilized eggs, indicating that long bristles are necessary for successful insemination. We also tested whether the evolution of bristle length was constrained by phenotypic correlations with other traits. Analyses of phenotypic covariation indicated that bristle length was highly correlated with other abdominal appendage traits, but was not correlated with abdominal sternite size. Thus, abdominal appendages are not exaggerated traits like many sexual ornaments, but vary independently from body size. At the same time, strong correlations between bristle length and appendage length suggest that selection on bristle length is likely to result in a correlated increase in appendage length. Bristle length is under sexual selection in T. biloba and has the potential to evolve independently from abdomen size. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Anatomic variation and orgasm: Could variations in anatomy explain differences in orgasmic success?

PubMed

Emhardt, E; Siegel, J; Hoffman, L

2016-07-01

Though the public consciousness is typically focused on factors such as psychology, penis size, and the presence of the "G-spot," there are other anatomical and neuro-anatomic differences that could play an equal, or more important, role in the frequency and intensity of orgasms. Discovering these variations could direct further medical or procedural management to improve sexual satisfaction. The aim of this study is to review the available literature of anatomical sexual variation and to explain why this variation may predispose some patients toward a particular sexual experience. In this review, we explored the available literature on sexual anatomy and neuro-anatomy. We used PubMed and OVID Medline for search terms, including orgasm, penile size variation, clitoral variation, Grafenberg spot, and benefits of orgasm. First we review the basic anatomy and innervation of the reproductive organs. Then we describe several anatomical variations that likely play a superior role to popular known variation (penis size, presence of g-spot, etc). For males, the delicate play between the parasympathetic and sympathetic nervous systems is vital to achieve orgasm. For females, the autonomic component is more complex. The clitoris is the primary anatomical feature for female orgasm, including its migration toward the anterior vaginal wall. In conclusions, orgasms are complex phenomena involving psychological, physiological, and anatomic variation. While these variations predispose people to certain sexual function, future research should explore how to surgically or medically alter these. Clin. Anat. 29:665-672, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Study of quality of life in patients with benign prostatic hyperplasia under treatment with silodosin.

PubMed

Castro-Díaz, D; Callejo, D; Cortés, X; Pérez, M

2014-01-01

To assess the impact of urinary symptoms associated with benign prostatic hyperplasia and its treatment with silodosin, on quality of life (QoL) and sexual function, depending on age, severity of symptoms, time on treatment and prostate size. A cross-sectional, observational study was conducted in 305 urology practices all around Spain. Socio-demographic and clinical data were collected and patients filled the following questionnaires: EQ-5D, Sexual Function Index (SFI) and International Prostate Symptom Score (IPSS). Multiple regression models were used to determine factors independently associated with patients' QoL. A total of 1,019 patients were enrolled, mean (SD) for: age 62.7 (5.7), EQ-5D 89.9 (13.9), sexual drive-SFI 3.71 (1.67), erection-SFI 6.11 (3.08), ejaculation-SFI 4.50 (2.06) problems-SFI 6.85 (3.37) and overall satisfaction-SFI 2.00 (0.99). The EQ-5D and SFI score were statistically lower with: older age, severe LUTS and greater prostate size (P<.01), but no differences were found related to time on treatment with silodosin. The EQ-5D score was positively associated with sexual satisfaction and desire size of SFI and the EQ-5D VAS score, and negatively with disability, semi-urban residence and comorbidities in the multiple regression analyses. Severe LUTS and older age are associated to a greater deterioration in sexual function and quality of life. However time on treatment with silodosin does not produce deterioration in the quality of life. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

Sexual selection on morphological and physiological traits and fluctuating asymmetry in the black scavenger fly Sepsis cynipsea.

PubMed

Blanckenhorn, W U; Kraushaar, U R S; Teuschl, Y; Reim, C

2004-05-01

Previous univariate studies of the fly Sepsis cynipsea (Diptera: Sepsidae) have demonstrated spatiotemporally variable and consequently overall weak sexual selection favouring large male size, which is nevertheless stronger on average than fecundity selection favouring larger females. To identify specific target(s) of selection on body size and additional traits possibly affecting mating success, two multivariate field studies of sexual selection were conducted. In one study using seasonal replicates from three populations, we assessed 15 morphological traits. No clear targets of sexual selection on male size could be detected, perhaps because spatiotemporal variation in selection was again strong. In particular, there was no (current) selection on male abdomen length or fore coxa length, the only traits for which S. cynipsea males are not smaller than females. Interestingly, copulating males had a consistently shorter fore femur base, a secondary sexual trait, and a wider clasper (hypopygium) gap, an external genital trait. In a second study using daily and seasonal replicates from one population, we included physiological measures of energy reserves (lipids, glucose, glycogen), in addition to hind tibia length and fluctuating asymmetry (FA) of all pairs of legs. This study again confirmed the mating advantage of large males, and additionally suggests independent positive influences of lipids (the long-term energy stores), with effects of glucose and glycogen (the short-term energy stores) tending to be negative. FA of paired traits was not associated with male mating success. Our study suggests that inclusion of physiological measures and genital traits in phenomenological studies of selection, which is rare, would be fruitful in other species.

Foot, leg, and ankle swelling

MedlinePlus

... feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema ... 31. Trayes KP, Studdiford JS, Pickle S, Tully AS. Edema: diagnosis and management. Am Fam Physician . 2013;88( ...

Processes and controls in swelling anhydritic clay rocks

NASA Astrophysics Data System (ADS)

Mutschler, Thomas; Blum, Philipp; Butscher, Christoph

2015-04-01

Referring to the swelling of anhydritic clay rocks in tunneling, Leopold Müller-Salzburg noted in the third volume on tunneling of his fundamental text book on rock engineering that "a truly coherent explanation of these phenomena is still owing" (Müller-Salzburg 1978, p. 306). This valuation is still true after more than three decades of research in the field of swelling anhydritic clay rocks. One of the reasons is our limited knowledge of the processes involved in the swelling of such rocks, and of the geological, mineralogical, hydraulic, chemical and mechanical controls of the swelling. In this contribution, a review of processes in swelling anhydritic clay rocks and of associated controls is presented. Also numerical models that aim at simulating the swelling processes and controls are included in this review, and some of the remaining open questions are pointed out. By focusing on process-oriented work in this review, the presentation intends to stimulate further research across disciplines in the field of swelling anhydritic clay rocks to finally get a step further in managing the swelling problem in geotechnical engineering projects. Keywords: swelling; anhydritic clay rocks; review

Conditioned same-sex partner preference in male rats is facilitated by oxytocin and dopamine: effect on sexually dimorphic brain nuclei.

PubMed

Triana-Del Rio, Rodrigo; Tecamachaltzi-Silvarán, Miriam B; Díaz-Estrada, Victor X; Herrera-Covarrubias, Deissy; Corona-Morales, Aleph A; Pfaus, James G; Coria-Avila, Genaro A

2015-04-15

Conditioned same-sex partner preference can develop in male rats that undergo cohabitation under the effects of quinpirole (QNP, D2 agonist). Herein, we assessed the development of conditioned same-sex social/sexual preference in males that received either nothing, saline, QNP, oxytocin (OT), or QNP+OT during cohabitation with another male (+) or single-caged (-). This resulted in the following groups: (1) Intact-, (2) Saline+, (3) QNP-, (4) OT-, (5) QNP+, (6) OT+ and (7) QNP/OT+. Cohabitation occurred during 24h in a clean cage with a male partner that bore almond scent on the back as conditioned stimulus. This was repeated every 4 days for a total of three trials. Social and sexual preference were assessed four days after the last conditioning trial in a drug-free test in which experimental males chose between the scented familiar male and a novel sexually receptive female. Results showed that males from groups Intact-, Saline+, QNP- and OT- displayed a clear preference for the female (opposite-sex), whereas groups QNP+, OT+ and QNP/OT+ displayed socio/sexual preference for the male partner (same-sex). In Experiment 2, the brains were processed for Nissl dye and the area size of two sexually dimorphic nuclei (SDN-POA and SON) was compared between groups. Males from groups OT-, OT+ and QNP/OT+ expressed a smaller SDN-POA and groups QNP+ and QNP/OT+ expressed a larger SON. Accordingly, conditioned same-sex social/sexual partner preference can develop during cohabitation under enhanced D2 or OT activity but such preference does not depend on the area size of those sexually dimorphic nuclei. Copyright © 2015 Elsevier B.V. All rights reserved.

Sexual identity, attraction and behaviour in Britain: The implications of using different dimensions of sexual orientation to estimate the size of sexual minority populations and inform public health interventions.

PubMed

Geary, Rebecca S; Tanton, Clare; Erens, Bob; Clifton, Soazig; Prah, Philip; Wellings, Kaye; Mitchell, Kirstin R; Datta, Jessica; Gravningen, Kirsten; Fuller, Elizabeth; Johnson, Anne M; Sonnenberg, Pam; Mercer, Catherine H

2018-01-01

Sexual orientation encompasses three dimensions: sexual identity, attraction and behaviour. There is increasing demand for data on sexual orientation to meet equality legislation, monitor potential inequalities and address public health needs. We present estimates of all three dimensions and their overlap in British men and women, and consider the implications for health services, research and the development and evaluation of public health interventions. Analyses of data from Britain's third National Survey of Sexual Attitudes and Lifestyles, a probability sample survey (15,162 people aged 16-74 years) undertaken in 2010-2012. A lesbian, gay or bisexual (LGB) identity was reported by 2·5% of men and 2·4% of women, whilst 6·5% of men and 11·5% of women reported any same-sex attraction and 5·5% of men and 6·1% of women reported ever experience of same-sex sex. This equates to approximately 547,000 men and 546,000 women aged 16-74 in Britain self-identifying as LGB and 1,204,000 men and 1,389,000 women ever having experience of same-sex sex. Of those reporting same-sex sex in the past 5 years, 28% of men and 45% of women identified as heterosexual. There is large variation in the size of sexual minority populations depending on the dimension applied, with implications for the design of epidemiological studies, targeting and monitoring of public health interventions and estimating population-based denominators. There is also substantial diversity on an individual level between identity, behaviour and attraction, adding to the complexity of delivering appropriate services and interventions.

Sexual identity, attraction and behaviour in Britain: The implications of using different dimensions of sexual orientation to estimate the size of sexual minority populations and inform public health interventions

PubMed Central

Erens, Bob; Clifton, Soazig; Prah, Philip; Wellings, Kaye; Mitchell, Kirstin R.; Datta, Jessica; Gravningen, Kirsten; Fuller, Elizabeth; Johnson, Anne M.; Sonnenberg, Pam; Mercer, Catherine H.

2018-01-01

Background Sexual orientation encompasses three dimensions: sexual identity, attraction and behaviour. There is increasing demand for data on sexual orientation to meet equality legislation, monitor potential inequalities and address public health needs. We present estimates of all three dimensions and their overlap in British men and women, and consider the implications for health services, research and the development and evaluation of public health interventions. Methods Analyses of data from Britain’s third National Survey of Sexual Attitudes and Lifestyles, a probability sample survey (15,162 people aged 16–74 years) undertaken in 2010–2012. Findings A lesbian, gay or bisexual (LGB) identity was reported by 2·5% of men and 2·4% of women, whilst 6·5% of men and 11·5% of women reported any same-sex attraction and 5·5% of men and 6·1% of women reported ever experience of same-sex sex. This equates to approximately 547,000 men and 546,000 women aged 16–74 in Britain self-identifying as LGB and 1,204,000 men and 1,389,000 women ever having experience of same-sex sex. Of those reporting same-sex sex in the past 5 years, 28% of men and 45% of women identified as heterosexual. Interpretation There is large variation in the size of sexual minority populations depending on the dimension applied, with implications for the design of epidemiological studies, targeting and monitoring of public health interventions and estimating population-based denominators. There is also substantial diversity on an individual level between identity, behaviour and attraction, adding to the complexity of delivering appropriate services and interventions. PMID:29293516

Pollen transfer efficiency and its effect on inflorescence size in deceptive pollination strategies.

PubMed

Scopece, G; Schiestl, F P; Cozzolino, S

2015-03-01

Pollination systems differ in pollen transfer efficiency, a variable that may influence the evolution of flower number. Here we apply a comparative approach to examine the link between pollen transfer efficiency and the evolution of inflorescence size in food and sexually deceptive orchids. We examined pollination performance in nine food-deceptive, and eight sexually deceptive orchids by recording pollen removal and deposition in the field. We calculated correlations between reproductive success and flower number (as a proxy for resources allocated during reproductive process), and directional selection differentials were estimated on flower number for four species. Results indicate that sexually deceptive species experience decreased pollen loss compared to food-deceptive species. Despite producing fewer flowers, sexually deceptive species attained levels of overall pollination success (through male and female function) similar to food-deceptive species. Furthermore, a positive correlation between flower number and pollination success was observed in food-deceptive species, but this correlation was not detected in sexually deceptive species. Directional selection differentials for flower number were significantly higher in food compared to sexually deceptive species. We suggest that pollination systems with more efficient pollen transfer and no correlation between pollination success and number of flowers produced, such as sexual deception, may allow the production of inflorescences with fewer flowers that permit the plant to allocate fewer resources to floral displays and, at the same time, limit transpiration. This strategy can be particularly important for ecological success in Mediterranean water-deprived habitats, and might explain the high frequency of sexually deceptive species in these specialised ecosystems. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Does Sexy Media Promote Teen Sex? A Meta-Analytic and Methodological Review.

PubMed

Ferguson, Christopher J; Nielsen, Rune K L; Markey, Patrick M

2017-06-01

Parents and policy makers are often concerned that sexy media (media depicting or discussing sexual encounters) may promote sexual behavior in young viewers. There has been some debate among scholars regarding whether such media promote sexual behaviors. It remains unclear to what extent sexy media is a risk factor for increased sexual behavior among youth. The current study employed a meta-analysis of 22 correlational and longitudinal studies of sexy media effects on teen sexual behavior (n = 22,172). Moderator analyses examined methodological and science culture issues such as citation bias. Results indicated the presence only of very weak effects. General media use did not correlate with sexual behaviors (r = 0.005), and sexy media use correlated only weakly with sexual behaviors (r = 0.082) once other factors had been controlled. Higher effects were seen for studies with citation bias, and lower effects when family environment is controlled. The impact of media on teen sexuality was minimal with effect sizes near to zero.

High-risk sexual activity in the House and Ball community: influence of social networks.

PubMed

Schrager, Sheree M; Latkin, Carl A; Weiss, George; Kubicek, Katrina; Kipke, Michele D

2014-02-01

We investigated the roles of House membership and the influence of social and sexual network members on the sexual risk behavior of men in the Los Angeles House and Ball community. From February 2009 to January 2010, male participants (n = 233) completed interviewer-assisted surveys during a House meeting or Ball event. We used logistic regression to model the effects of sexual network size, influence of sexual network members, House membership status, and their interactions on high-risk sex. Significant predictors of high-risk sex included number of sexual partners in the nominated social network, multiethnicity, and previous diagnosis of sexually transmitted infection. House membership was protective against high-risk sex. Additionally, a 3-way interaction emerged between number of sexual partners in the network, influence, and network members' House membership. Future research should assess network members' attitudes and behavior in detail to provide a greater understanding of the dynamics of social influence and to identify additional avenues for intervention.

Analysis of sexual behavior in adolescents.

PubMed

Teva, Inmaculada; Bermudez, M Paz; Ramiro, Maria T; Ramiro-Sanchez, Tamara

2013-10-01

The aim of this study was to describe some characteristics of vaginal, anal and oral sexual behavior in Spanish adolescents. It was a cross-sectional descriptive population study conducted using a probabilistic sample survey. The sample was composed of 4,612 male and female adolescents, of whom 1,686 reported having penetrative sexual experience. Sample size was established with a 97% confidence level and a 3% estimation error. Data collection took place in secondary education schools. Mean age of vaginal sex initiation was 15 years. Compared to females, males reported an earlier age of anal and oral sex initiation and a larger number of vaginal and anal sexual partners. Males also reported a higher frequency of penetrative sexual relations under the influence of alcohol or other drugs. A higher percentage of females than males reported not using a condom in their first anal sexual experience. This study provides a current overview of the sexual behavior of adolescents that can be useful for the design of future programs aimed at preventing HIV and sexually transmitted infections (STIs).

Body Image and Marital Satisfaction: Evidence for the Mediating Role of Sexual Frequency and Sexual Satisfaction

PubMed Central

Meltzer, Andrea L.; McNulty, James K.

2010-01-01

How does women’s body image shape their interpersonal relationships? Based on recent theories of risk regulation and empirical evidence that sex is an emotionally risky behavior for women, we predicted that women’s body image would predict increased sexual frequency and thus increased sexual and marital satisfaction for both partners. The current study of 53 recently married couples provided results consistent with this prediction. Specifically, wives’ perceptions of their sexual attractiveness were positively associated with both wives’ and husbands’ marital satisfaction, controlling for wives’ body size, wives’ global self-esteem, wives’ neuroticism, and reports of whether or not the couple was trying to get pregnant, and both of these associations were mediated by increased sexual frequency and higher sexual satisfaction. Notably, wives’ perceptions of their sexual attractiveness uniquely accounted for 6% of the variance in husbands’ marital satisfaction and 19% of the variance in wives’ marital satisfaction. Accordingly, marital interventions may greatly benefit by addressing women’s body esteem. PMID:20438191

Evaluation of the swelling behaviour of iota-carrageenan in monolithic matrix tablets.

PubMed

Kelemen, András; Buchholcz, Gyula; Sovány, Tamás; Pintye-Hódi, Klára

2015-08-10

The swelling properties of monolithic matrix tablets containing iota-carrageenan were studied at different pH values, with measurements of the swelling force and characterization of the profile of the swelling curve. The swelling force meter was linked to a PC by an RS232 cable and the measured data were evaluated with self-developed software. The monitor displayed the swelling force vs. time curve with the important parameters, which could be fitted with an Analysis menu. In the case of iota-carrageenan matrix tablets, it was concluded that the pH and the pressure did not influence the swelling process, and the first section of the swelling curve could be fitted by the Korsmeyer-Peppas equation. Copyright © 2015 Elsevier B.V. All rights reserved.

Sexual Dimorphism of Body Size Is Controlled by Dosage of the X-Chromosomal Gene Myc and by the Sex-Determining Gene tra in Drosophila.

PubMed

Mathews, Kristina Wehr; Cavegn, Margrith; Zwicky, Monica

2017-03-01

Drosophila females are larger than males. In this article, we describe how X -chromosome dosage drives sexual dimorphism of body size through two means: first, through unbalanced expression of a key X -linked growth-regulating gene, and second, through female-specific activation of the sex-determination pathway. X -chromosome dosage determines phenotypic sex by regulating the genes of the sex-determining pathway. In the presence of two sets of X -chromosome signal elements (XSEs), Sex-lethal ( Sxl ) is activated in female ( XX ) but not male ( XY ) animals. Sxl activates transformer ( tra ), a gene that encodes a splicing factor essential for female-specific development. It has previously been shown that null mutations in the tra gene result in only a partial reduction of body size of XX animals, which shows that other factors must contribute to size determination. We tested whether X dosage directly affects animal size by analyzing males with duplications of X -chromosomal segments. Upon tiling across the X chromosome, we found four duplications that increase male size by >9%. Within these, we identified several genes that promote growth as a result of duplication. Only one of these, Myc , was found not to be dosage compensated. Together, our results indicate that both Myc dosage and tra expression play crucial roles in determining sex-specific size in Drosophila larvae and adult tissue. Since Myc also acts as an XSE that contributes to tra activation in early development, a double dose of Myc in females serves at least twice in development to promote sexual size dimorphism. Copyright © 2017 by the Genetics Society of America.

Swell Sleeves for Testing Explosive Devices

NASA Technical Reports Server (NTRS)

Hinkel, Todd J.; Dean, Richard J.; Hohmann, Carl W.; Hacker, Scott C.; Harrington, Douglas W.; Bacak, James W.

2003-01-01

A method of testing explosive and pyrotechnic devices involves exploding the devices inside swell sleeves. Swell sleeves have been used previously for measuring forces. In the present method, they are used to obtain quantitative indications of the energy released in explosions of the devices under test. A swell sleeve is basically a thick-walled, hollow metal cylinder threaded at one end to accept a threaded surface on a device to be tested (see Figure 1). Once the device has been tightly threaded in place in the swell sleeve, the device-and-swell-sleeve assembly is placed in a test fixture, then the device is detonated. After the explosion, the assembly is removed from the test fixture and placed in a coordinate-measuring machine for measurement of the diameter of the swell sleeve as a function of axial position. For each axial position, the original diameter of the sleeve is subtracted from the diameter of the sleeve as swollen by the explosion to obtain the diametral swelling as a function of axial position (see Figure 2). The amount of swelling is taken as a measure of the energy released in the explosion. The amount of swelling can be compared to a standard amount of swelling to determine whether the pyrotechnic device functioned as specified.

Common symptoms during pregnancy

MedlinePlus

... keep your gums healthy Swelling, Varicose Veins, and Hemorrhoids Swelling in your legs is common. You may ... In your rectum, veins that swell are called hemorrhoids. To reduce swelling: Raise your legs and rest ...

Evidence of a temperature transition for denuded zone formation in nanocrystalline Fe under He irradiation

DOE PAGES

El-Atwani, Osman; Nathaniel II, James E.; Leff, Asher C.; ...

2016-10-18

Nanocrystalline materials are radiation-tolerant materials’ candidates due to their high defect sink density. Here, nanocrystalline iron films were irradiated with 10 keV helium ions in situ in a transmission electron microscope at elevated temperatures. Grain-size-dependent bubble density changes and denuded zone occurrence were observed at 700 K, but not at 573 K. This transition, attributed to increased helium–vacancy migration at elevated temperatures, suggests that nanocrystalline microstructures are more resistant to swelling at 700 K due to decreased bubble density. Finally, denuded zone formation had no correlation with grain size and misorientation angle under the conditions studied.

Self-assessment of genital anatomy, sexual sensitivity and function in women: implications for genitoplasty.

PubMed

Schober, Justine M; Meyer-Bahlburg, Heino F L; Ransley, Philip G

2004-09-01

To assess the perceptions of healthy women of their genital anatomy and sexual sensitivity, and to provide suggestions for genitoplasty based on this information, as the success of genitoplasty has historically relied upon the surgeon's perception of the patient's anatomy and function, rather than the patient's perception of outcome in terms of appearance and erotic sensitivity. Fifty healthy, sexually active, adult women (aged 20-56 years) with no history of genital surgery completed the female version of the Self-Assessment of Genital Anatomy and Sexual Function. This self- report questionnaire comprises written text and images enabling women to rate the appearance, size and position of clitoris and vagina, as well as the intensity of orgasm and effort required for achieving orgasm in specified areas around the clitoris and within the vagina. Anatomical locations were compared for these ratings by repeated-measures analysis of variance. Anatomically, 46% of women described their clitoris as 'moderate-sized and raised', 42% as 'small and raised', and 78% reported that their vaginal opening was adequate for sexual penetration. The women reported the strongest orgasm and least effort to obtain an orgasm with stimulation of the area on and above the clitoris. For vaginal sensitivity, scores for orgasm intensity increased, and for orgasm effort decreased, with increasing vaginal depth, and they indicated less sexual sensitivity for the vagina than for the external genitalia. The skin above the clitoris, and the clitoris itself, appeared to be the most sexually sensitive. During genitoplasty, attention to preserving skin-flap integrity in this area seems appropriate.

Improvement of Expansive Soils Using Chemical Stabilizers

NASA Astrophysics Data System (ADS)

Ikizler, S. B.; Senol, A.; Khosrowshahi, S. K.; Hatipoğlu, M.

2014-12-01

The aim of this study is to investigate the effect of two chemical stabilizers on the swelling potential of expansive soil. A high plasticity sodium bentonite was used as the expansive soil. The additive materials including fly ash (FA) and lime (L) were evaluated as potential stabilizers to decrease the swelling pressure of bentonite. Depending on the type of additive materials, they were blended with bentonite in different percentages to assess the optimum state and approch the maximum swell pressure reduction. According to the results of swell pressure test, both fly ash and lime reduce the swelling potential of bentonite but the maximum improvement occurs using bentonite-lime mixture while the swelling pressure reduction approaches to 49%. The results reveal a significant reduction of swelling potential of expansive soil using chemical stabilizers. Keywords: Expansive soil; swell pressure; chemical stabilization; fly ash; lime

The energy costs of sexual dimorphism in mole-rats are morphological not behavioural

PubMed Central

Scantlebury, M; Speakman, J.R; Bennett, N.C

2005-01-01

Different reproductive strategies of males and females may lead to the evolution of differences in their energetic costs of reproduction, overall energetic requirements and physiological performances. Sexual dimorphism is often associated with costly behaviours (e.g. large males might have a competitive advantage in fighting, which is energetically expensive). However, few studies of mammals have directly compared the energy costs of reproductive activities between sexes. We compared the daily energy expenditure (DEE) and resting metabolic rate (RMR) of males and females of two species of mole-rat, Bathyergus janetta and Georychus capensis (the former is sexually dimorphic in body size and the latter is not) during a period of intense digging when males seek females. We hypothesized that large body size might be indicative of greater digging or fighting capabilities, and hence greater mass-independent DEE values in males of the sexually dimorphic species. In contrast to this prediction, although absolute values of DEE were greater in B. janetta males, mass-independent values were not. No differences were apparent between sexes in G. capensis. By comparison, although RMR values were greater in B. janetta than G. capensis, no differences were apparent between the sexes for either species. The energy cost of dimorphism is most likely to be the cost of maintenance of a large body size, and not the cost of behaviours performed when an individual is large. PMID:16519235

The use of gamma irradiation in preparation of polybutadiene rubber nanopowder; Its effect on particle size, morphology and crosslink structure of the powder

NASA Astrophysics Data System (ADS)

Rezaei Abadchi, Majid; Jalali-Arani, Azam

2014-02-01

The aim of this work was the preparation and characterization of polybutadiene rubber (BR) powder by irradiating of rubber lattices using 60Co radiation and spray-drying of them at the appropriate condition. The influences of absorbed dose on the volume swelling ratio, molecular weight between crosslinks, gel fraction, and glass transition temperature of obtained powder were studied. Morphology, size and size distribution of rubber particles were examined by using scanning electron microscopy (SEM) and laser particle size analyzer (LPSA) technique, respectively. Results obtained by LPSA revealed that radiation has no effect on particle size of rubber latex but after drying, adherence properties of rubber particle causes increase in particle size of rubber powder, as shown in SEM photograph. Fourier transform infrared spectroscopy of rubber powders confirmed that with increasing the irradiation dose, characteristic peak corresponds to the >Cdbnd C< double bands decreased. Also Charlesby-Pinner equation was used to evaluate radiation yield.

Endogenous pH-responsive nanoparticles with programmable size changes for targeted tumor therapy and imaging applications.

PubMed

Wu, Wei; Luo, Li; Wang, Yi; Wu, Qi; Dai, Han-Bin; Li, Jian-Shu; Durkan, Colm; Wang, Nan; Wang, Gui-Xue

2018-01-01

Nanotechnology-based antitumor drug delivery systems, known as nanocarriers, have demonstrated their efficacy in recent years. Typically, the size of the nanocarriers is around 100 nm. It is imperative to achieve an optimum size of these nanocarriers which must be designed uniquely for each type of delivery process. For pH-responsive nanocarriers with programmable size, changes in pH (~6.5 for tumor tissue, ~5.5 for endosomes, and ~5.0 for lysosomes) may serve as an endogenous stimulus improving the safety and therapeutic efficacy of antitumor drugs. This review focuses on current advanced pH-responsive nanocarriers with programmable size changes for anticancer drug delivery. In particular, pH-responsive mechanisms for nanocarrier retention at tumor sites, size reduction for penetrating into tumor parenchyma, escaping from endo/lysosomes, and swelling or disassembly for drug release will be highlighted. Additional trends and challenges of employing these nanocarriers in future clinical applications are also addressed.

Correlates of Sexual Abuse and Smoking among French Adults

ERIC Educational Resources Information Center

King, Gary; Guilbert, Philippe; Ward, D. Gant; Arwidson, Pierre; Noubary, Farzad

2006-01-01

Objective: The goal of this study was to examine the association between sexual abuse (SA) and initiation, cessation, and current cigarette smoking among a large representative adult population in France. Method: A random sample size of 12,256 adults (18-75 years of age) was interviewed by telephone concerning demographic variables, health…

Beyond the Absence of Disease or Infirmity: The Case for Sexual Wellness

ERIC Educational Resources Information Center

Daugherty, Timothy K.; Julian, Hannah M.; Lynch, Nicole M.; Chen, Stephanie J.; Whipple, Tanya L.; Ginsburg, Austin F.

2016-01-01

Examined a version of the Substance Abuse and Mental Health Services Administration (SAMHSA) wellness model that was revised to include a ninth factor, sexual wellness: "understanding the human body, choosing the type and size of one's family, and experiencing satisfaction (alone or with consenting others) while maintaining autonomy,…

Sexual Assault Education Programs: A Meta-Analytic Examination of Their Effectiveness

ERIC Educational Resources Information Center

Anderson, Linda A.; Whiston, Susan C.

2005-01-01

Meta-analyses of the effectiveness of college sexual assault education programs on seven outcome measure categories were conducted using 69 studies that involved 102 treatment interventions and 18,172 participants. Five of the outcome categories had significant average effect sizes (i.e., rape attitudes, rape-related attitudes, rape knowledge,…

Extensive swelling of the limb and systemic symptoms after a fourth dose of acellular pertussis containing vaccines in England in children aged 3-6years.

PubMed

Southern, Jo; Waight, Pauline A; Andrews, Nick; Miller, Elizabeth

2017-01-23

Extensive limb swelling (ESL) after a booster dose of acellular pertussis (aP) containing vaccine can cause concern and has the potential to be confused with cellulitis. In the United Kingdom aP-containing vaccine was introduced for primary immunisation at 2, 3 and 4months of age in 2004, with the first cohorts eligible to receive a fourth dose in 2007 at school entry. We assessed the frequency of ESL (here defined as swelling >100mms diameter) in 973 children receiving a fourth dose of one of four aP vaccines given combined with inactivated polio, tetanus and either low dose diphtheria (TdaP/IPV) or high dose diphtheria (DTaP/IPV) vaccine; 2 of the 3 DTaP/IPV vaccines also contained Haemophilus influenza b conjugate vaccine (Hib). Post-vaccination symptoms and local reactions were recorded in 7-day diaries or by a telephone follow up if no diary was returned. Local swellings >50mm diameter were reported by 2.2% TdaP/IPV recipients compared with 6.6-11.1% of DTaP/IPV recipients; the corresponding proportions for redness >50mms was 7.0% for TdaP/IPV and 13.3-17.7% for DTaP/IPV recipients. Among the latter, the addition of Hib did not affect the frequency or size of local reactions. Pain at the injection site and systemic symptoms did not differ between the four vaccine groups. A history of atopy was not associated with development of local swelling or redness. A total of 13 children (1.3%) experienced an ESL, three after TdaP/IPV. ESLs resolved without systemic upset within a few days and were usually painless; medical advice was only sought for two children. Parents should be informed about the possible occurrence of an ESL with the pre-school aP-containing booster vaccine but can be reassured that it is a benign and transient condition. Copyright © 2016 Elsevier Ltd. All rights reserved.

High temperatures disrupt Artemia franciscana mating patterns and impact sexual selection intensity

NASA Astrophysics Data System (ADS)

Santos, Maria R.; Vieira, Natividade; Monteiro, Nuno M.

2018-07-01

Temperature plays a critical role in survival and reproduction, especially in ectotherms. Therefore, it is important to understand the mechanisms influencing life history traits and reproductive behaviours in order to predict climate change impacts on species' occurrence and performance. Here, we used the crustacean Artemia franciscana to investigate the potential impacts of temperature on life history traits, mating patterns and intensity of sexual selection. We reared A. franciscana at three temperatures 20 °C, 25 °C, and 30 °C and measured life history traits such as growth, mortality or development of sexual traits. Our observations confirmed a clear link between life history traits and temperature, with advanced sexual maturity and increased mortality rates following temperature rises. Also, we found that mating is size assortative close to the ideal developmental temperature. Nevertheless, when temperatures deviate from the optimum, mating patterns were altered. Although selection intensity for females remained similar at all tested temperatures, as males preferentially mated with the larger females, size assortative mating disappeared at the highest temperature. Overall, our results highlight the potential for a temperature-dependent disruption of A. franciscana mating patterns. This disruption is especially pronounced under high temperatures as reproduction becomes progressively more random, thus entailing a relaxation of sexual selection intensity.

Gold nanoparticles induced cloudy swelling to hydropic degeneration, cytoplasmic hyaline vacuolation, polymorphism, binucleation, karyopyknosis, karyolysis, karyorrhexis and necrosis in the liver.

PubMed

Abdelhalim, Mohamed Anwar K; Jarrar, Bashir M

2011-09-22

Nanoparticles (NPs) can potentially cause adverse effects on organ, tissue, cellular, subcellular and protein levels due to their unusual physicochemical properties. Advances in nanotechnology have identified promising candidates for many biological and biomedical applications. The aim of the present study was to investigate the particle-size, dose and exposure duration effects of gold nanoparticles (GNPs) on the hepatic tissue in an attempt to cover and understand the toxicity and their potential therapeutic and diagnostic use. A total of 70 healthy male Wistar-Kyoto rats were exposed to GNPs received 50 or 100 ul of GNPs infusion of size (10, 20 and 50 nm for 3 or 7 days) to investigate particle-size, dose and exposure duration effects of GNPs on the hepatic tissue. In comparison with respective control rats, exposure to GNPs doses has produced alterations in the hepatocytes, portal triads and the sinusoids. The alterations in the hepatocytes were mainly vacuolar to hydropic degeneration, cytopasmic hyaline vacuolation, polymorphism, binucleation, karyopyknosis, karyolysis, karyorrhexis and necrosis. The hepatocytes swelling might be exhibited as a result of disturbances of membranes function that lead to massive influx of water and Na+ due to GNPs effects accompanied by leakage of lysosomal hydrolytic enzymes that lead to cytoplasmic degeneration and macromolecular crowding. Hydropic degeneration is a result of ion and fluid homestasis that lead to an increase of intracellular water. The vacuolated swelling of the cytoplasm of the hepatocytes of the GNPs treated rats might indicate acute and subacute liver injury induced by the GNPs. Binucleation represents a consequence of cell injury and is a sort of chromosomes hyperplasia which is usually seen in regenerating cells. The induced histological alterations might be an indication of injured hepatocytes due to GNPs toxicity that became unable to deal with the accumulated residues resulting from metabolic and structural disturbances caused by these NPs. These alterations were size-dependent with smaller ones induced the most effects and related with time exposure of GNPs. The appearance of hepatocytes cytoplasmic degeneration and nuclear destruction may suggest that GNPs interact with proteins and enzymes of the hepatic tissue interfering with the antioxidant defense mechanism and leading to reactive oxygen species (ROS) generation which in turn may induce stress in the hepatocytes to undergo atrophy and necrosis. More histomorphologcal, histochemical and ultrastrucural investigations are needed in relation of the application of GNPs with their potential role as a therapeutic and diagnostic tool.

Gold nanoparticles induced cloudy swelling to hydropic degeneration, cytoplasmic hyaline vacuolation, polymorphism, binucleation, karyopyknosis, karyolysis, karyorrhexis and necrosis in the liver

PubMed Central

2011-01-01

Background Nanoparticles (NPs) can potentially cause adverse effects on organ, tissue, cellular, subcellular and protein levels due to their unusual physicochemical properties. Advances in nanotechnology have identified promising candidates for many biological and biomedical applications. The aim of the present study was to investigate the particle-size, dose and exposure duration effects of gold nanoparticles (GNPs) on the hepatic tissue in an attempt to cover and understand the toxicity and their potential therapeutic and diagnostic use. Methods A total of 70 healthy male Wistar-Kyoto rats were exposed to GNPs received 50 or 100 ul of GNPs infusion of size (10, 20 and 50 nm for 3 or 7 days) to investigate particle-size, dose and exposure duration effects of GNPs on the hepatic tissue. Results In comparison with respective control rats, exposure to GNPs doses has produced alterations in the hepatocytes, portal triads and the sinusoids. The alterations in the hepatocytes were mainly vacuolar to hydropic degeneration, cytopasmic hyaline vacuolation, polymorphism, binucleation, karyopyknosis, karyolysis, karyorrhexis and necrosis. Conclusions The hepatocytes swelling might be exhibited as a result of disturbances of membranes function that lead to massive influx of water and Na+ due to GNPs effects accompanied by leakage of lysosomal hydrolytic enzymes that lead to cytoplasmic degeneration and macromolecular crowding. Hydropic degeneration is a result of ion and fluid homestasis that lead to an increase of intracellular water. The vacuolated swelling of the cytoplasm of the hepatocytes of the GNPs treated rats might indicate acute and subacute liver injury induced by the GNPs. Binucleation represents a consequence of cell injury and is a sort of chromosomes hyperplasia which is usually seen in regenerating cells. The induced histological alterations might be an indication of injured hepatocytes due to GNPs toxicity that became unable to deal with the accumulated residues resulting from metabolic and structural disturbances caused by these NPs. These alterations were size-dependent with smaller ones induced the most effects and related with time exposure of GNPs. The appearance of hepatocytes cytoplasmic degeneration and nuclear destruction may suggest that GNPs interact with proteins and enzymes of the hepatic tissue interfering with the antioxidant defense mechanism and leading to reactive oxygen species (ROS) generation which in turn may induce stress in the hepatocytes to undergo atrophy and necrosis. More histomorphologcal, histochemical and ultrastrucural investigations are needed in relation of the application of GNPs with their potential role as a therapeutic and diagnostic tool. PMID:21939512

Loop and void damage during heavy ion irradiation on nanocrystalline and coarse grained tungsten: Microstructure, effect of dpa rate, temperature, and grain size

DOE Office of Scientific and Technical Information (OSTI.GOV)

El-Atwani, O.; Esquivel, E.; Efe, M.

Displacement damage, through heavy ion irradiation was studied on two tungsten grades (coarse grained tungsten (CGW) and nanocrystalline and ultrafine grained tungsten (NCW)) using different displacement per atom rates and different irradiation temperatures (RT and 1050 K). Percentage of <111> and <100> type loops at the irradiation conditions was determined. Irradiation damage in the microstructure was quantified using average loop areas and densities (method A) and loop areal fraction in the grain matrices under 2-beam diffraction conditions (method B). Average values of <111> and <100> loops were calculated from method A. Loop coalescence was shown to occur for CGW atmore » 0.25 dpa. Using both methods of quantifying microstructural damage, no effect of dpa rate was observed and damage in CGW was shown to be the same at RT and 1050 K. Swelling from voids observed at 1050 K was quantified. The loop damage in NCW was compared to CGW at the same diffraction and imaging conditions. NCW was shown to possess enhanced irradiation resistance at RT regarding loop damage and higher swelling resistance at 1050 K compared to CGW. For irradiation at 1050 K, the NCW was shown to have a similar defect densities to the CGW which is attributed to higher surface effects in the CGW, vacancy loop growth to voids and a better sink efficiency in the CGW deduced from the vacancy distribution profiles from Kinetic Monte Carlo simulations. Loop density and swelling was shown to have similar values in grains sizes that range from 80-600 nm. No loop or void denuded zones occurred at any of the irradiation conditions. This work has a collection of experiments and conclusions that are of vital importance to materials and nuclear communities.« less

Loop and void damage during heavy ion irradiation on nanocrystalline and coarse grained tungsten: Microstructure, effect of dpa rate, temperature, and grain size

DOE PAGES

El-Atwani, O.; Esquivel, E.; Efe, M.; ...

2018-02-20

Displacement damage, through heavy ion irradiation was studied on two tungsten grades (coarse grained tungsten (CGW) and nanocrystalline and ultrafine grained tungsten (NCW)) using different displacement per atom rates and different irradiation temperatures (RT and 1050 K). Percentage of <111> and <100> type loops at the irradiation conditions was determined. Irradiation damage in the microstructure was quantified using average loop areas and densities (method A) and loop areal fraction in the grain matrices under 2-beam diffraction conditions (method B). Average values of <111> and <100> loops were calculated from method A. Loop coalescence was shown to occur for CGW atmore » 0.25 dpa. Using both methods of quantifying microstructural damage, no effect of dpa rate was observed and damage in CGW was shown to be the same at RT and 1050 K. Swelling from voids observed at 1050 K was quantified. The loop damage in NCW was compared to CGW at the same diffraction and imaging conditions. NCW was shown to possess enhanced irradiation resistance at RT regarding loop damage and higher swelling resistance at 1050 K compared to CGW. For irradiation at 1050 K, the NCW was shown to have a similar defect densities to the CGW which is attributed to higher surface effects in the CGW, vacancy loop growth to voids and a better sink efficiency in the CGW deduced from the vacancy distribution profiles from Kinetic Monte Carlo simulations. Loop density and swelling was shown to have similar values in grains sizes that range from 80-600 nm. No loop or void denuded zones occurred at any of the irradiation conditions. This work has a collection of experiments and conclusions that are of vital importance to materials and nuclear communities.« less

Temporal and Spatial Scales of Sub-Continental Mantle Convection: Comparison of Modern and Geological Observations of Dynamic Support

NASA Astrophysics Data System (ADS)

Jones, S. M.; Lovell, B.; Crosby, A. G.

2011-12-01

The topographies of Africa and Antarctica form patterns of interlocking swells. The admittance between swell topography and free-air gravity indicates that these swells are dynamically supported by mantle convection, with swell diameters of 1850±450 km and full heights between 800 and 1800 m. The implication is that mantle convection not only supports swells surrounding hotspots but also influences topography across the entire surface areas of Africa and Antarctica. Topographic swells and associated gravity anomalies with diameters over 1000 km are observed on other continents and throughout the oceans. Numerical models support the idea that dynamically supported swell topography is a worldwide phenomenon. We investigate whether dynamically supported swells are also observed throughout the geological record, focussing on intensively studied Mesozoic- Cenozoic sedimentary rocks around Britain and Ireland. Since 200 Ma, this region was affected by three dynamically supported swells that peaked during the Middle Jurassic, Early Cretaceous and Eocene (c. 175, 146 and 56 Ma), each several thousand kilometres in diameter, and the region now lies on the edge of the modern swell centred on Iceland. The diameters and maximum heights of the Mesozoic British swells and the modern African and Antarctic swells are similar. The ancient British swells grew in 5--10 Myr and decayed over 20--30 Myr, suggesting vertical motion rates comparable to those estimated from geomorphological studies of Africa. Igneous production rate and swell height are not correlated in the modern and the geological records. Vertical motions of Britain and Ireland, a typical piece of continental lithosphere far from a destructive plate boundary, have been demonstrably affected by convective support for over half of the past 200 Ma period. Mantle convection should be considered as a common control on regional sea-level at time periods from 10s down to 1 Myr or less, and with vertical motion rates in the order 10s to 100s m/Myr.

Appraisal of jaw swellings in a Nigerian tertiary healthcare facility.

PubMed

Lasisi, Taye J; Adisa, Akinyele O; Olusanya, Adeola A

2013-02-01

The mandible and maxilla can be the site of myriads of lesions that may be categorized as neoplastic, cystic, reactive and infective or inflammatory. Literature reviewing jaw swellings in an amalgamated fashion are uncommon, probably because aetiologies for these swellings are varied. However, to appreciate their relative relationship, it is essential to evaluate the clinico-pathologic profile of jaw swellings. The aim of this appraisal is to describe the array of jaw swellings seen at our hospital from 1990 to 2011, to serve as a reference database. Biopsy records of all histologically diagnosed cases of jaw swellings seen at the department of Oral Pathology, University College Hospital between January 1990 and December 2011 were retrieved, coded and inputted into SPSS version 20. Data on prevalence, age, sex, site and histological diagnosis were analysed descriptively for each category of jaw swellings. All patients below 16 years were regarded as children. A total of 638 jaw swellings were recorded in the 22-year study period. The Non Odontogenic Tumours (NOT) were the commonest, accounting for 46.2% of all jaw swellings. Odontogenic Tumours (OT) formed 45% of all adult jaw swelling while it formed 25.2% in children and adolescents. Ameloblastoma was the commonest while the most common NOT was ossifying fibroma (OF). Chronic osteomyelitis of the jaws was about 6 times commoner in adult females than males and mostly involved the mandible. The most common malignant jaw swelling was Burkitts' lymphoma (BL) that was about 7 times more in children than adults. Osteogenic sarcoma was the most common malignancy in adults. Jaw swellings are extensively varied in types and pattern of occurrence. This study has categorized jaw swellings in a simple but comprehensive fashion to allow for easy referencing in local and international data acquisition and epidemiological comparison. Key words:Jaw swellings, odontogenic, Nigeria.

Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Damast, Shari, E-mail: shari.damast@yale.edu; Alektiar, Kaled M.; Goldfarb, Shari

Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from <6 months to >5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, basedmore » on the published validation study. Results: SD was reported by 81% of respondents. The mean ({+-} standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 ({+-}2.0); orgasm, 2.5 ({+-}2.4); desire, 2.4 ({+-}1.3); arousal, 2.2 ({+-}2.0); dryness, 2.1 ({+-}2.1); and pain, 1.9 ({+-}2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, -7.1 points; 95% CI, -11.2 to -3.1; P<.001), lack of vaginal lubricant use (effect size, -4.4 points; 95% CI, -8.7 to -0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, -4.6 points; 95% CI, -9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.« less

Comparisons of body sizes at sexual maturity and at sex change in the parrotfishes of Hawaii: input needed for management regulations and stock assessments.

PubMed

DeMartini, E E; Howard, K G

2016-02-01

First estimates of sex allocation patterns and body size-at-sexual maturity and at protogynous sex change are presented for the five major (including one endemic) species of parrotfishes of Hawaii. Median body size at initial maturation as a female (LM50) and at protogynous sex change from adult female to adult male (LΔ50) varied greatly among the five species. Estimates of LM50 were about 14, 17, 24, 34 and 35 cm fork length (LF) in palenose Scarus psittacus, Pacific bullethead Chlorurus spilurus, stareye Calotomus carolinus, spectacled Chlorurus perspicillatus and redlip parrotfish Scarus rubroviolaceus. Values of LΔ50 were c. 23, 27, 37, 46 and 47 cm LF in the respective species. Length at female maturation was proportional to maximum body size (Lmax) of the respective species, ranging from 50 to 72% and averaging 62% of Lmax across species. LΔ50 was also proportional to Lmax, ranging from 82 to 97% and averaging 92%. Males of both pairs of Scarus and Chlorurus spp. reported here are diandric. Only one of the five major species (C. carolinus) is functionally monandric, with either all or nearly all males secondarily derived from adult females. The broadly differing absolute body sizes at sexual maturation and at sex change among the five species have important implications for improving regulatory size limits for parrotfishes in the State of Hawaii, where parrotfish species have historically been managed based on a single minimum size limit of 30·5 cm LF. This study provides a model demonstration of why catch data for parrotfishes, and other size-structured reef-fish populations, should be recorded either by species or by functional size-groups of species that allow setting more meaningful minimum size limits. © 2016 The Fisheries Society of the British Isles.

Site-Specific Pre-Swelling-Directed Morphing Structures of Patterned Hydrogels.

PubMed

Wang, Zhi Jian; Hong, Wei; Wu, Zi Liang; Zheng, Qiang

2017-12-11

Morphing materials have promising applications in various fields, yet how to program the self-shaping process for specific configurations remains a challenge. Herein we show a versatile approach to control the buckling of individual domains and thus the outcome configurations of planar-patterned hydrogels. By photolithography, high-swelling disc gels were positioned in a non-swelling gel sheet; the swelling mismatch resulted in out-of-plain buckling of the disc gels. To locally control the buckling direction, masks with holes were used to guide site-specific swelling of the high-swelling gel under the holes, which built a transient through-thickness gradient and thus directed the buckling during the subsequent unmasked swelling process. Therefore, various configurations of an identical patterned hydrogel can be programmed by the pre-swelling step with different masks to encode the buckling directions of separate domains. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diffusion and Swelling Measurements in Pharmaceutical Powder Compacts Using Terahertz Pulsed Imaging

PubMed Central

Yassin, Samy; Su, Ke; Lin, Hungyen; Gladden, Lynn F; Zeitler, J Axel

2015-01-01

Tablet dissolution is strongly affected by swelling and solvent penetration into its matrix. A terahertz-pulsed imaging (TPI) technique, in reflection mode, is introduced as a new tool to measure one-dimensional swelling and solvent ingress in flat-faced pharmaceutical compacts exposed to dissolution medium from one face of the tablet. The technique was demonstrated on three tableting excipients: hydroxypropylmethyl cellulose (HPMC), Eudragit RSPO, and lactose. Upon contact with water, HPMC initially shrinks to up to 13% of its original thickness before undergoing expansion. HPMC and lactose were shown to expand to up to 20% and 47% of their original size in 24 h and 13 min, respectively, whereas Eudragit does not undergo dimensional change. The TPI technique was used to measure the ingress of water into HPMC tablets over a period of 24 h and it was observed that water penetrates into the tablet by anomalous diffusion. X-ray microtomography was used to measure tablet porosity alongside helium pycnometry and was linked to the results obtained by TPI. Our results highlight a new application area of TPI in the pharmaceutical sciences that could be of interest in the development and quality testing of advanced drug delivery systems as well as immediate release formulations. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:1658–1667, 2015 PMID:25645509

Diffusion and swelling measurements in pharmaceutical powder compacts using terahertz pulsed imaging.

PubMed

Yassin, Samy; Su, Ke; Lin, Hungyen; Gladden, Lynn F; Zeitler, J Axel

2015-05-01

Tablet dissolution is strongly affected by swelling and solvent penetration into its matrix. A terahertz-pulsed imaging (TPI) technique, in reflection mode, is introduced as a new tool to measure one-dimensional swelling and solvent ingress in flat-faced pharmaceutical compacts exposed to dissolution medium from one face of the tablet. The technique was demonstrated on three tableting excipients: hydroxypropylmethyl cellulose (HPMC), Eudragit RSPO, and lactose. Upon contact with water, HPMC initially shrinks to up to 13% of its original thickness before undergoing expansion. HPMC and lactose were shown to expand to up to 20% and 47% of their original size in 24 h and 13 min, respectively, whereas Eudragit does not undergo dimensional change. The TPI technique was used to measure the ingress of water into HPMC tablets over a period of 24 h and it was observed that water penetrates into the tablet by anomalous diffusion. X-ray microtomography was used to measure tablet porosity alongside helium pycnometry and was linked to the results obtained by TPI. Our results highlight a new application area of TPI in the pharmaceutical sciences that could be of interest in the development and quality testing of advanced drug delivery systems as well as immediate release formulations. © 2015 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association.

Where do all the maternal effects go? Variation in offspring body size through ontogeny in the live-bearing fish Poecilia parae.

PubMed

Lindholm, Anna K; Hunt, John; Brooks, Robert

2006-12-22

Maternal effects are an important source of adaptive variation, but little is known about how they vary throughout ontogeny. We estimate the contribution of maternal effects, sire genetic and environmental variation to offspring body size from birth until 1 year of age in the live-bearing fish Poecilia parae. In both the sexes, maternal effects on body size were initially high in juveniles, and then declined to zero at sexual maturity. In sons, this was accompanied by a sharp rise in sire genetic variance, consistent with the expression of Y-linked loci affecting male size. In daughters, all variance components decreased with time, consistent with compensatory growth. There were significant negative among-dam correlations between early body size and the timing of sexual maturity in both sons and daughters. However, there was no relationship between early life maternal effects and adult longevity, suggesting that maternal effects, although important early in life, may not always influence late life-history traits.

Intra-operative Iodine-125 prostatic implant following bilateral pelvic lymphadenectomy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwong, E.W.H.; Huh, S.H.; Nobler, M.P.

Sixty-five patients with prostatic adenocarcinoma Stages B and C were treated with intraoperative Iodine-125 prostatic implantation following bilateral pelvic lymphadenectomy. Pelvic nodal metastases were found in 31% of the patients. All the patients have been followed for a period of 1 1/2 to 6 years. Serial digital rectal examination revealed complete regression of the palpable disease in 15% of the patients at 6 months, 47% at 1 year, and 87% at 2 years. Post-operative complications were also evaluated: 13% of the patients became sexually impotent, 11% had impaired potency after the procedure, and 26% of patients complained of dry ejaculation;more » and 17% developed scrotal and/or penile swelling, which persisted up to 14 months, but usually subsided within 5 months. Two patients developed local recurrence.« less

Are men better than women at acoustic size judgements?

PubMed

Charlton, Benjamin D; Taylor, Anna M; Reby, David

2013-08-23

Formants are important phonetic elements of human speech that are also used by humans and non-human mammals to assess the body size of potential mates and rivals. As a consequence, it has been suggested that formant perception, which is crucial for speech perception, may have evolved through sexual selection. Somewhat surprisingly, though, no previous studies have examined whether sexes differ in their ability to use formants for size evaluation. Here, we investigated whether men and women differ in their ability to use the formant frequency spacing of synthetic vocal stimuli to make auditory size judgements over a wide range of fundamental frequencies (the main determinant of vocal pitch). Our results reveal that men are significantly better than women at comparing the apparent size of stimuli, and that lower pitch improves the ability of both men and women to perform these acoustic size judgements. These findings constitute the first demonstration of a sex difference in formant perception, and lend support to the idea that acoustic size normalization, a crucial prerequisite for speech perception, may have been sexually selected through male competition. We also provide the first evidence that vocalizations with relatively low pitch improve the perception of size-related formant information.

Symptoms Experienced and Information Needs of Women Receiving Chemotherapy.

PubMed

Uysal, Neşe; Toprak, Filiz Ünal; Kutlutsürkan, Sevinç; Erenel, Ayten Şentürk

2018-01-01

This study is carried out to determine the symptoms and information necessity on chemotherapy (CT) treatment of the women with breast cancer. A total of 170 women older than 18 years old, who receive CT with breast cancer diagnosis, are volunteered to participate in the study. Mixed method was used in the study. Data are collected using Descriptive Data Form, Interview Form and Memorial Symptom Assessment Scale. As a result of the cluster analysis, four clusters and the symptoms within have been obtained. These are: pain, lack of energy, feeling drowsy, sweat, swelling of hands, and feet in the first cluster; feeling nervous, difficulty sleeping, feeling sad, worrying in the second cluster; nausea, feeling bloating, change in the way food tastes, hair loss, constipation in the third cluster; vomiting, diarrhea, problems with sexual interest, lack of appetite, dizziness, and weight loss in the forth cluster. Women's information necessity related to the CT are follows: the effects of CT, other treatment options beyond CT, complementary methods, the effect of the CT treatment on reproductive health and sexuality, nutrition, and symptom control. The results of this study will enable determination of symptom clusters, which health professionals are easier to focus on these symptoms. An understanding information need of patients can help to ensure that individual's coping strategies and self-management.

Using video playback to study the effect of an audience on male mating behavior in the Sailfin molly (Poecilia latipinna).

PubMed

Makowicz, A M; Plath, M; Schlupp, I

2010-09-01

Sexual conflict in poeciliid fishes is well-documented, particularly male sexual harassment and its effects on females. For instance, male attempts to force copulations influence female feeding, energy allocation, and preference for shoaling partners. However, there has been little research conducted to determine how the social environment shapes the occurrence and intensity of sexual harassment. In this study we ask whether an audience male influences the sexual behaviors of a focal male, the correlated feeding time reduction of female Poecilia latipinna, and if the size of the audience male (larger or smaller than the focal male) influences these behaviors. We presented a video of a male, either smaller or larger than the focal male, or an empty tank (control) to a female interacting with a male or female partner and measured feeding times and sexual behaviors. We found that male sexual behaviors increased in the presence of an audience male, especially if the audience male was larger than the focal male. Females fed more in the presence of a partner female than in the presence of a male, which was independent of the audience (i.e., video treatment). Focal female aggression towards the partner female increased with the size of the audience male. The present study shows that an audience male has multiple interacting influences on both male and female behavior. Copyright 2010 Elsevier B.V. All rights reserved.

Growth, size and age at maturity of the agile frog (Rana dalmatina) in an Iberian Peninsula population.

PubMed

Sarasola-Puente, Vanessa; Gosá, Alberto; Oromí, Neus; Madeira, María José; Lizana, Miguel

2011-06-01

The mean age of a population of agile frogs (Rana dalmatina) from the Iberian Peninsula was estimated using mark and recapture and skeletochronology. Life-history parameters, including growth rate, body length, age and size at maturity, sexual dimorphism and longevity, were studied. The regression between age and snout-vent length (SVL) was highly significant in both sexes. Males reached sexual maturity at two years of age, although sometimes they can reach it at only one year of age. The average SVL at maturity was 51.75 mm (standard error (SE)=0.71; n=45). Females reached sexual maturity at two years of age with an average SVL of 62.14 mm (SE=2.20; n=14). A subset of the female population reached sexual maturity at three years of age. Growth was rapid until sexual maturity was reached. There was an overlap of SVL between different age classes. Growth was continuous, fulfilling the conditions of Von Bertalanffy's model. The growth coefficient (K) was 0.840 in males and 0.625 in females. The maximum SVL was greater in females (73.00 mm) than in males (59.50mm). Sexual dimorphism was significantly biased towards females in all age classes. The maximum longevity observed was 6 years in females and 8 years in males. Management strategies for agile frogs should take into account factors such as these life-history characteristics. Copyright © 2011 Elsevier GmbH. All rights reserved.

An ecological framework for sexual minority women's health: factors associated with greater body mass.

PubMed

Eliason, Michele J; Fogel, Sarah C

2015-01-01

In recent years, many studies have focused on the body of sexual minority women, particularly emphasizing their larger size. These studies rarely offer theoretically based explanations for the increased weight, nor study the potential consequences (or lack thereof) of being heavier. This article provides a brief overview of the multitude of factors that might cause or contribute to larger size of sexual minority women, using an ecological framework that elucidates upstream social determinants of health as well as individual risk factors. This model is infused with a minority stress model, which hypothesizes excess strain resulting from the stigma associated with oppressed minority identities such as woman, lesbian, bisexual, woman of color, and others. We argue that lack of attention to the upstream social determinants of health may result in individual-level victim blaming and interventions that do not address the root causes of minority stress or increased weight.

Do summer temperatures trigger spring maturation in pacific lamprey, Entosphenus tridentatus?

USGS Publications Warehouse

Clemens, B.J.; Van De Wetering, S.; Kaufman, J.; Holt, R.A.; Schreck, C.B.

2009-01-01

Pacific lamprey, Entosphenus tridentatus, return to streams and use somatic energy to fuel maturation. Body size decreases, the lamprey mature, spawn, and then die. We predicted that warm, summer temperatures (>20 ??C) would accentuate shrinkage in body size, and expedite sexual maturation and subsequent death. We compared fish reared in the laboratory at diel fluctuating temperatures of 20-24 ??C (mean = 21.8 ??C) with fish reared at cooler temperatures (13.6 ??C). The results confirmed our predictions. Lamprey from the warm water group showed significantly greater proportional decreases in body weight following the summer temperature treatments than fish from the cool water group. A greater proportion of warm water fish sexually matured (100%) and died (97%) the following spring than cool water fish (53% sexually mature, 61% died). Females tended to mature and die earlier than males, most obviously in the warm water group. ?? 2009 John Wiley & Sons A/S.

Intra- and Interspecific Interactions as Proximate Determinants of Sexual Dimorphism and Allometric Trajectories in the Bottlenose Dolphin Tursiops truncatus (Cetacea, Odontoceti, Delphinidae)

PubMed Central

2016-01-01

Feeding adaptation, social behaviour, and interspecific interactions related to sexual dimorphism and allometric growth are particularly challenging to be investigated in the high sexual monomorphic Delphinidae. We used geometric morphometrics to extensively explore sexual dimorphism and ontogenetic allometry of different projections of the skull and the mandible of the bottlenose dolphin Tursiops truncatus. Two-dimensional landmarks were recorded on the dorsal, ventral, lateral, and occipital views of the skull, and on the lateral view of the left and the right mandible of 104 specimens from the Mediterranean and the North Seas, differing environmental condition and degree of interspecific associations. Landmark configurations were transformed, standardized and superimposed through a Generalized Procrustes Analysis. Size and shape differences between adult males and females were respectively evaluated through ANOVA on centroid size, Procrustes ANOVA on Procrustes distances, and MANOVA on Procrustes coordinates. Ontogenetic allometry was investigated by multivariate regression of shape coordinates on centroid size in the largest homogenous sample from the North Sea. Results evidenced sexual dimorphic asymmetric traits only detected in the adults of the North Sea bottlenose dolphins living in monospecific associations, with females bearing a marked incision of the cavity hosting the left tympanic bulla. These differences were related to a more refined echolocalization system that likely enhances the exploitation of local resources by philopatric females. Distinct shape in immature versus mature stages and asymmetric changes in postnatal allometry of dorsal and occipital traits, suggest that differences between males and females are established early during growth. Allometric growth trajectories differed between males and females for the ventral view of the skull. Allometric trajectories differed among projections of skull and mandible, and were related to dietary shifts experienced by subadults and adults. PMID:27764133

Feeding habits, sexual dimorphism and size at maturity of the lizard Cnemidophorus ocellifer (Spix, 1825) (Teiidae) in a reforested restinga habitat in northeastern Brazil.

PubMed

Santana, G G; Vasconcellos, A; Gadelha, Y E A; Vieira, W L S; Almeida, W O; Nóbrega, R P; Alves, R R N

2010-05-01

The feeding habits, the sexual dimorphism in size and sexual maturity of the actively foraging lizard Cnemidophorusocellifer were analysed in an area of a reforested Restinga habitat located in the municipality of Mataraca, along the northern-most coast of Paraíba State, Brazil. Seventy-five specimens of C. ocellifer were examined (46 males and 29A females). Of this total, only 23 specimens had prey in their stomachs. The most frequent prey consumed items were orthopterans (50%), coleopterans (23.9%) and arachnids (10.9%); termites and insect larvae were less consumed (both with 2.2%). There were no significant differences observed between the numbers of prey consumed by either males or females. There were significant differences in SVL (snout-vent length) between the sexes, with males attaining larger SVL values. When the influence of SVL was removed from the analyses, sexual dimorphism in the form was still reflected in the head size of these lizards. Sexual maturity in females and males was attained with SVL of 42.2 and 49.0 mm respectively. Although no significant difference was observed between the SVL of the females and the number of eggs produced, there was a clear tendency for larger females to produce more eggs. The low structural complexity of the vegetation and the poor soil quality in the reforested restinga area examined does not furnish favourable habitat for insect and termite larvae, contributing to the marked differences in the diet of the population of C. ocellifer observed in the present study in relation to the diet of their conspecifics in undisturbed areas of restinga, cerrado and caatinga.

Morphometric Differentiation in Cornops aquaticum (Orthoptera: Acrididae): Associations With Sex, Chromosome, and Geographic Conditions

PubMed Central

Romero, María Luciana; Colombo, Pablo César; Remis, María Isabel

2014-01-01

Abstract The water-hyacinth grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) is native to South America and inhabits lowlands from southern Mexico to central Argentina and Uruguay. This grasshopper feeds and lays eggs on species from the genera Eichhornia and Pontederia. Particularly, Eichhornia crassipes is considered “the world’s worst water weed,” and the release of C. aquaticum was proposed as a form of biological control. Morphometric variation on the chromosomally differentiated populations from the middle and lower Paraná River and its possible association with geographic, sex, and chromosomal conditions was analyzed. Significant phenotype variation in C. aquaticum population was detected. C. aquaticum presents body-size sexual dimorphism, females being bigger than males. Female-biased sexual size dimorphism for all five analyzed traits was detected. The assessment of variation in sexual size dimorphism for tegmen length showed that this trait scaled allometrically, indicating that males and females did not vary in a similar fashion. The detected allometry was consistent with Rensch’s rule demonstrating greater evolutionary divergence in male size than in female size and suggests that males are more sensitive to environmental condition. The analysis of morphometric variation in the context of chromosome constitution showed that the presence of fusion 1/6 was related to body-size variation. Fusion carriers displayed bigger body size than standard homozygotes. Besides, a positive relationship between tegmen length and the number of fused chromosomes was detected, showing a chromosome dose effect. Because the highest frequency of fusions has been found in the lower Paraná River, a marginal environment for this species, the results found would support the hypothesis that some supergenes located in the fusions may be favored in the southern populations, thus contributing to the establishment and maintenance of the polymorphism. PMID:25399431

Function-related Drivers of Skull Morphometric Variation and Sexual Size Dimorphism in a Subterranean Rodent, Plateau Zokor (Eospalax baileyi).

PubMed

Su, Junhu; Hegab, Ibrahim M; Ji, Weihong; Nan, Zhibiao

2018-05-01

Sexual dimorphism is prevalent in most living organisms. The difference in size between sexes of a given species is generally known as sexual size dimorphism (SSD). The magnitude of the SSD is determined by Rensch's rule where size dimorphism increases with increasing body size when the male is the larger sex and decreases with increasing average body size when the female is the larger sex. The unique underground environment that zokors ( Eospalax baileyi ) live under in the severe habitat of the Qinghai-Tibetan Plateau (QTP) could create SSD selection pressures that may or may not be supported by Rensch's rule, making this scientific question worthy of investigation. In this study, we investigated the individual variation between sexes in body size and SSD of plateau zokors using measurements of 19 morphological traits. We also investigated the evolutionary mechanisms underlying SSD in plateau zokors. Moreover, we applied Rensch's rule to all extant zokor species. Our results showed male-biased SSD in plateau zokors: The body- and head-related measurements were greater in males than in females. Linear regression analysis between body length, body weight, and carcass weight showed significant relationships with some traits such as skull length, lower incisor length, and tympanic bulla width, which might support our prediction that males have faster growth rates than females. Further, the SSD pattern corroborated the assumption of Rensch's rule in plateau zokors but not in the other zokor species. Our findings suggest that the natural underground habitat and behavioral differences between sexes can generate selection pressures on male traits and contribute to the evolution of SSD in plateau zokors.

Development of rat female genital cortex and control of female puberty by sexual touch

PubMed Central

Lenschow, Constanze; Sigl-Glöckner, Johanna

2017-01-01

Rat somatosensory cortex contains a large sexually monomorphic genital representation. Genital cortex undergoes an unusual 2-fold expansion during puberty. Here, we investigate genital cortex development and female rat sexual maturation. Ovariectomies and estradiol injections suggested sex hormones cause the pubertal genital cortex expansion but not its maintenance at adult size. Genital cortex expanded by thalamic afferents invading surrounding dysgranular cortex. Genital touch was a dominant factor driving female sexual maturation. Raising female rats in contact with adult males promoted genital cortex expansion, whereas contact to adult females or nontactile (audio-visual-olfactory) male cues did not. Genital touch imposed by human experimenters powerfully advanced female genital cortex development and sexual maturation. Long-term blocking of genital cortex by tetrodotoxin in pubescent females housed with males prevented genital cortex expansion and decelerated vaginal opening. Sex hormones, sexual experience, and neural activity shape genital cortex, which contributes to the puberty promoting effects of sexual touch. PMID:28934203

Development of rat female genital cortex and control of female puberty by sexual touch.

PubMed

Lenschow, Constanze; Sigl-Glöckner, Johanna; Brecht, Michael

2017-09-01

Rat somatosensory cortex contains a large sexually monomorphic genital representation. Genital cortex undergoes an unusual 2-fold expansion during puberty. Here, we investigate genital cortex development and female rat sexual maturation. Ovariectomies and estradiol injections suggested sex hormones cause the pubertal genital cortex expansion but not its maintenance at adult size. Genital cortex expanded by thalamic afferents invading surrounding dysgranular cortex. Genital touch was a dominant factor driving female sexual maturation. Raising female rats in contact with adult males promoted genital cortex expansion, whereas contact to adult females or nontactile (audio-visual-olfactory) male cues did not. Genital touch imposed by human experimenters powerfully advanced female genital cortex development and sexual maturation. Long-term blocking of genital cortex by tetrodotoxin in pubescent females housed with males prevented genital cortex expansion and decelerated vaginal opening. Sex hormones, sexual experience, and neural activity shape genital cortex, which contributes to the puberty promoting effects of sexual touch.

Tracking the attenuation and nonbreaking dissipation of swells using altimeters

NASA Astrophysics Data System (ADS)

Jiang, Haoyu; Stopa, Justin E.; Wang, He; Husson, Romain; Mouche, Alexis; Chapron, Bertrand; Chen, Ge

2016-02-01

A method for systematically tracking swells across oceanic basins is developed by taking advantage of high-quality data from space-borne altimeters and wave model output. The evolution of swells is observed over large distances based on 202 swell events with periods ranging from 12 to 18 s. An empirical attenuation rate of swell energy of about 4 × 10-7 m-1 is estimated using these observations, and the nonbreaking energy dissipation rates of swells far away from their generating areas are also estimated using a point source model. The resulting acceptance range of nonbreaking dissipation rates is -2.5 to 5.0 × 10-7 m-1, which corresponds to a dissipation e-folding scales of at least 2000 km for steep swells, to almost infinite for small-amplitude swells. These resulting rates are consistent with previous studies using in-situ and synthetic aperture radar (SAR) observations. The frequency dispersion and angular spreading effects during swell propagation are discussed by comparing the results with other studies, demonstrating that they are the two dominant processes for swell height attenuation, especially in the near field. The resulting dissipation rates from these observations can be used as a reference for ocean engineering and wave modeling, and for related studies such as air-sea and wind-wave-turbulence interactions.

Pattern of sexually transmitted infections in males in interior Sindh: a 10-year-study.

PubMed

Bhutto, Abdul Manan; Shah, Aftab Hussain; Ahuja, Dileep Kumar; Solangi, Aijaz Hussain; Shah, Sharaf Ali

2011-01-01

Sexually transmitted infections (STIs) are widespread in Pakistan and have not been fully documented particularly in Sindh Province. The aim of this study is to determine the number and clinical pattern of various types of STIs in general population of Larkana division and its surrounding cities. A hospital based prospective study was carried out at Male-STD-Clinic in the Department of Dermatology, Shaheed Muhtarma Benazir Bhutto Medical University Hospital Larkana from January 2000 to December 2009. Among 4,288 patients, 3,947 (92.04%) had the history of extra marital sexual contact and simultaneously had developed the clinical signs of STIs; 341 (7.95%) had history of extra marital sexual contact but did not have the manifestation of STIs. Majority of the patients (3,860, 90.01%) had the history of heterosexual contact with different partners, but only few 171 (3.98%) of them had the history of homosexual contact. According the syndromic diagnosis 1930 (45.00%) patients had genital ulcer (including herpes genitals) with or without skin manifestations, 690 (16.09%) had urethral discharge, 431 (10.05%) had genital warts, 349 (8.14%) had lesions other than STIs related, 304 (7.08%) had more than one syndrome, 193 (4.50%) had scrotal swelling, 46 (1.07%) had inguinal bubo, 3 (0.06%) were human immunodeficiency virus (HIV) positive, and 1 (0.02%) had ophthalmia neonatorum. Based on the clinical and etiological grounds: 2560 (59.70%) had syphilis, 640 (14. 92%) had gonorrhoea, 399 (9.30%) had mixed infections, 40 (0.93%) had chancroid, 431 (10.05%) had genital warts, 40 (0.93%) had lymphogranuloma venerum (LGV) and granuloma inguinale (GI), 3 (0.06%) were HIV positive, 208 (4.85%) had genital herpes, 120 (2.79%) had orchitis, 56 (1.30%) had non gonococcal urethritis (chlamydia were 19), and 1 (0.02%) had ophthalmia neonatorum. Mode of transmission of STIs in this region is mainly by heterosexual contact and syphilis is the commonest followed by gonorrhoea.

Why are reproductively parasitic fish males so small?—influence of tactic-specific selection

NASA Astrophysics Data System (ADS)

Ota, Kazutaka; Kohda, Masanori; Sato, Tetsu

2010-12-01

Despite the wide prevalence of alternative reproductive tactics, little attention has been paid to why reproductively parasitic males are so small. In this study, we tackled this issue in a shell-brooding fish Lamprologus callipterus. Sneaky `dwarf males' of this fish remain much smaller than bourgeois conspecifics throughout their life and employ a unique parasitic tactic, i.e. entering into a gastropod shell where a female is spawning, passing through the space between the female and shell wall and staying behind her to ejaculate throughout the spawning event. Here, we tested the prediction that they remain small to get past her through the shell spaces by interpopulation comparison. We showed, across populations, a negative allometry for sexual size dimorphism, an exponential increase of female size with an increase in shell size and a negative correlation between the magnitude of sexual size dimorphism and shell size. These results suggest that the inner spaces strongly regulate dwarf male size. We conclude that the small bodies of dwarf males arise from adaptation to their unique reproductive behaviour.

Sexual dysfunction in women with ESRD requiring hemodialysis.

PubMed

Strippoli, Giovanni F M; Vecchio, Mariacristina; Palmer, Suetonia; De Berardis, Giorgia; Craig, Jonathan; Lucisano, Giuseppe; Johnson, David; Pellegrini, Fabio; Nicolucci, Antonio; Sciancalepore, Michela; Saglimbene, Valeria; Gargano, Letizia; Bonifati, Carmen; Ruospo, Marinella; Navaneethan, Sankar D; Montinaro, Vincenzo; Stroumza, Paul; Zsom, Marianna; Torok, Mariatta; Celia, Eduardo; Gelfman, Ruben; Bednarek-Skublewska, Anna; Dulawa, Jan; Graziano, Giusi; Gentile, Giorgio; Ferrari, Juan Nin; Santoro, Antonio; Zucchelli, Annalisa; Triolo, Giorgio; Maffei, Stefano; Hegbrant, Jörgen; Wollheim, Charlotta; De Cosmo, Salvatore; Manfreda, Valeria M

2012-06-01

The few existing studies of sexual dysfunction in women on hemodialysis are limited by small sample size. This large, cross-sectional study evaluated the prevalence and correlates of female sexual dysfunction in advanced kidney disease. DESIGN, SETTING, PARTICIPANTS, METHODS: A total of 1472 women with ESRD undergoing hemodialysis were recruited to a multinational, cross-sectional study conducted within a collaborative dialysis network in Europe and South America. Sexual dysfunction was identified by the Female Sexual Function Index. Correlates of self-reported sexual dysfunction were identified by regression analyses. Of the 1472 women, 659 completed questionnaires (45%). More than half (362 of 659 [55%]) lived with a partner, and 232 of 659 (35%) reported being sexually active. Of these 659 respondents, 555 (84%) reported sexual dysfunction. Women with a partner (282 of 362 [78%]) were less likely to report sexual dysfunction than those without a partner (273 of 297 [92%]) (P<0.001). Sexual dysfunction was independently associated with age, depressive symptoms, less education, menopause, diabetes, and diuretic therapy. Nearly all women who were not wait-listed for a kidney transplant and were living without a partner (249 of 260 [96%]) reported sexual dysfunction. More than half (128 of 232 [55%]) of sexually active women reported sexual dysfunction, associated with age, depressive symptoms, menopause, low serum albumin, and diuretic therapy. This descriptive study suggests most women on hemodialysis experience sexual problems. Additional research on the relevance of sexual dysfunction to symptom burden and quality of life in these women is needed.

Developmental temperature affects the expression of ejaculatory traits and the outcome of sperm competition in Callosobruchus maculatus.

PubMed

Vasudeva, R; Deeming, D C; Eady, P E

2014-09-01

The outcome of post-copulatory sexual selection is determined by a complex set of interactions between the primary reproductive traits of two or more males and their interactions with the reproductive traits of the female. Recently, a number of studies have shown the primary reproductive traits of both males and females express phenotypic plasticity in response to the thermal environment experienced during ontogeny. However, how plasticity in these traits affects the dynamics of sperm competition remains largely unknown. Here, we demonstrate plasticity in testes size, sperm size and sperm number in response to developmental temperature in the bruchid beetle Callosobruchus maculatus. Males reared at the highest temperature eclosed at the smallest body size and had the smallest absolute and relative testes size. Males reared at both the high- and low-temperature extremes produced both fewer and smaller sperm than males reared at intermediate temperatures. In the absence of sperm competition, developmental temperature had no effect on male fertility. However, under conditions of sperm competition, males reared at either temperature extreme were less competitive in terms of sperm offence (P(2)), whereas those reared at the lowest temperature were less competitive in terms of sperm defence (P(1)). This suggests the developmental pathways that regulate the phenotypic expression of these ejaculatory traits are subject to both natural and sexual selection: natural selection in the pre-ejaculatory environment and sexual selection in the post-ejaculatory environment. In nature, thermal heterogeneity during development is commonplace. Therefore, we suggest the interplay between ecology and development represents an important, yet hitherto underestimated component of male fitness via post-copulatory sexual selection. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

An upscaling method and a numerical analysis of swelling/shrinking processes in a compacted bentonite/sand mixture

NASA Astrophysics Data System (ADS)

Xie, M.; Agus, S. S.; Schanz, T.; Kolditz, O.

2004-12-01

This paper presents an upscaling concept of swelling/shrinking processes of a compacted bentonite/sand mixture, which also applies to swelling of porous media in general. A constitutive approach for highly compacted bentonite/sand mixture is developed accordingly. The concept is based on the diffuse double layer theory and connects microstructural properties of the bentonite as well as chemical properties of the pore fluid with swelling potential. Main factors influencing the swelling potential of bentonite, i.e. variation of water content, dry density, chemical composition of pore fluid, as well as the microstructures and the amount of swelling minerals are taken into account. According to the proposed model, porosity is divided into interparticle and interlayer porosity. Swelling is the potential of interlayer porosity increase, which reveals itself as volume change in the case of free expansion, or turns to be swelling pressure in the case of constrained swelling. The constitutive equations for swelling/shrinking are implemented in the software GeoSys/RockFlow as a new chemo-hydro-mechanical model, which is able to simulate isothermal multiphase flow in bentonite. Details of the mathematical and numerical multiphase flow formulations, as well as the code implementation are described. The proposed model is verified using experimental data of tests on a highly compacted bentonite/sand mixture. Comparison of the 1D modelling results with the experimental data evidences the capability of the proposed model to satisfactorily predict free swelling of the material under investigation. Copyright

Rethinking police training policies: large class sizes increase risk of police sexual misconduct.

PubMed

Reingle Gonzalez, Jennifer M; Bishopp, Stephen A; Jetelina, Katelyn K

2016-09-01

The limited research on police sexual misconduct (PSM), a common form of police misconduct, suggests that no evidence-based strategies for prevention are available for use by police departments. To identify new avenues for prevention, we critically evaluated 'front-end' police recruiting, screening, hiring and training procedures. Internal Affairs records were linked with administrative reports and police academy graduation data for officers accused of sexual assault or misconduct between 1994 and 2014. Logistic and proportional hazards regression methods were used to identify predictors of discharge for sustained allegations of PSM and time to discharge, respectively. Officer's graduating class size was positively associated with odds of discharge for PSM. For every one-officer increase in class size, the rate of discharge for PSM increased by 9% [hazard ratio (HR) = 1.09, P < 0.01]. For particularly large classes (>35 graduates), discharge rates were at least four times greater than smaller classes (HR = 4.43, P < 0.05). Large class sizes and more annual graduates increase rates of PSM. Officer recruitment strategies or training quality may be compromised during periods of intensive hiring. Trainee to instructor ratios or maximum class sizes may be instituted by academies to ensure that all police trainees receive the required supervision, one-on-one training, feedback and attention necessary to maximize public safety. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Controlling morphology in swelling-induced wrinkled surfaces

NASA Astrophysics Data System (ADS)

Breid, Derek Ronald

Wrinkles represent a pathway towards the spontaneous generation of ordered surface microstructure for applications in numerous fields. Examples of highly complex ordered wrinkle structures abound in Nature, but the ability to harness this potential for advanced material applications remains limited. This work focuses on understanding the relationship between the patterns on a wrinkled surface and the experimental conditions under which they form. Because wrinkles form in response to applied stresses, particular attention is given to the nature of the stresses in a wrinkling surface. The fundamental insight gained was then utilized to account for observed wrinkle formation phenomena within more complex geometric and kinetic settings. In order to carefully control and measure the applied stresses on a wrinkling film, a swelling-based system was developed using poly(dimethylsiloxane) (PDMS), surface-oxidized with a UV-ozone treatment. The swelling of the oxidized surface upon exposure to an ethanol vapor atmosphere was characterized using beam-bending experiments, allowing quantitative measurements of the applied stress. The wrinkle morphologies were characterized as a function of the overstress, defined as the ratio of the applied swelling stress to the critical buckling stress of the material. A transition in the dominant morphology of the wrinkled surfaces from dimple patterns to ridge patterns was observed at an overstress value of ˜2. The pattern dependence of wrinkles on the ratio of the principal stresses was examined by fabricating samples with a gradient prestress. When swollen, these samples exhibited a smooth morphological transition from non-equibiaxial to equibiaxial patterns, with prestrains as low as 2.5% exhibiting non-equibiaxial characteristics. This transition was seen both in samples with low and high overstresses. To explore the impact of these stress states in more complex geometries, wrinkling hemispherical surfaces with radii of curvature ranging from 50--1000 μm were fabricated using the same material system. Upon wrinkling, the hemispheres formed complex hierarchical assemblies reminiscent of naturally occurring structures. The curvature of a surface exhibited a correlation with its critical buckling stress, independent of other factors. This enables the surface curvature to be used as an independent control over the dimple-to-ridge transition which occurs as a function of overstress. As in the flat buckling surfaces, this transition was shown to occur at an overstress value of ˜2. Surface curvature was also shown to improve the observed hexagonal ordering of the dimple arrays, resulting in the formation of regular "golf ball" structures. Geometric effects in finite flat plates were also examined. Using circular masks during the oxidation process, plates with radii ranging from 0.4--8.6 mm were created. Upon wrinkling, a dimple-to-ridge transition was observed with increasing plate size, with the morphological switch occurring at a radius of ˜2 mm. This observed transition was not found to be due to the inherent mechanics of plates of different sizes, but instead to a reduction in the oxide conversion due to shadowing or stagnation caused by the masking process, which lowered the applied overstress. The shape of the finite plate was found to have little impact on the resulting wrinkle morphologies. Kinetic aspects of wrinkling were qualitatively characterized by observing the wrinkling process over the course of swelling. Wrinkling was observed to frontally propagate across the surface, and the ordering of the patterns which developed showed a qualitative correlation with the degree of uniformity in the advancing wrinkle front. Swelling with different solvents was found to lead to the formation of different patterns, based on the swelling kinetics of the UVO-treated PDMS upon exposure to each solvent.

The association between in-service sexual harassment and post-traumatic stress disorder among Department of Veterans Affairs disability applicants.

PubMed

Murdoch, Maureen; Polusny, Melissa A; Hodges, James; Cowper, Diane

2006-02-01

The goal was to describe the association between post-traumatic stress disorder (PTSD) and in-service sexual harassment in a nationally representative sample of Department of Veterans Affairs PTSD disability applicants. The study was a cross-sectional survey. Of 4,918 eligible veterans, 3,337 (68%) returned surveys. Nonresponse bias appeared to be minimal. After adjustment for other reported traumas, women's reported in-service sexual harassment severity was significantly associated with PTSD symptom severity (p < 0.0001). The effect seen was about the same size as that seen for combat exposure among the men and for in-service sexual assault among the women. Men showed no association between in-service sexual harassment and PTSD (p = 0.33), although power was low for this test. Sexual harassment significantly contributed to female veterans' PTSD symptoms; its contribution to men's symptoms was unclear. We discuss mechanisms through which sexual harassment might affect PTSD symptom severity, including the possibility that sexual harassment sometimes meets the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, definition of a criterion A stressor.

In vitro measurement of nucleus pulposus swelling pressure: A new technique for studies of spinal adaptation to gravity

NASA Technical Reports Server (NTRS)

Hargens, A. R.; Glover, M. G.; Mahmood, M. M.; Gott, S.; Garfin, S. R.; Ballard, R.; Murthy, G.; Brown, M. D.

1992-01-01

Swelling of the intervertebral disc nucleus pulposus is altered by posture and gravity. We have designed and tested a new osmometer for in vitro determination of nucleus pulposus swelling pressure. The functional principle of the osmometer involves compressing a sample of nucleus pulposus with nitrogen gas until saline pressure gradients across a 0.45 microns Millipore filter are eliminated. Swelling pressure of both pooled dog and pooled pig lumbar disc nucleus pulposus were measured on the new osmometer and compared to swelling pressures determined using the equilibrium dialysis technique. The osmometer measured swelling pressures comparable to those obtained by the dialysis technique. This osmometer provides a rapid, direct, and accurate measurement of swelling pressure of the nucleus pulposus.

Objectification in Virtual Romantic Contexts: Perceived Discrepancies between Self and Partner Ideals Differentially affect Body Consciousness in Women and Men

PubMed Central

Overstreet, Nicole M.; Quinn, Diane M.; Marsh, Kerry L.

2015-01-01

The current study examined whether exposure to sexually objectifying images in a potential romantic partner's virtual apartment affects discrepancies between people's perception of their own appearance (i.e., self-perceptions) and their perception of the body ideal that is considered desirable to a romantic partner (i.e., partner-ideals). Participants were 114 heterosexual undergraduate students (57 women and 57 men) from a northeastern U.S. university. The study used a 2 (Participant Gender) x 2 (Virtual Environment: Sexualized vs. Non-Sexualized) between-subjects design. We predicted that women exposed to sexually objectifying images in a virtual environment would report greater discrepancies between their self-perceptions and partner-ideals than men, which in turn would contribute to women's body consciousness. Findings support this hypothesis and show that perceived discrepancies account for the relationship between exposure to sexually objectifying images and body consciousness for women but not men. We also found gender asymmetries in objectification responses when each component of perceived discrepancies, i.e., self-perceptions versus perceptions of a romantic partner's body ideal, were examined separately. For men, exposure to muscular sexualized images was significantly associated with their self-perceptions but not their perceptions of the body size that is considered desirable to a romantic partner. For women, exposure to thin sexualized images was significantly associated with their perceptions that a romantic partner preferred a woman with a smaller body size. However, exposure to these images did not affect women's self-perceptions. Implications for gender asymmetries in objectification responses and perceived discrepancies that include a romantic partner's perceptions are discussed. PMID:26594085

Self-Esteem, Confidence, and Relationships in Men Treated with Sildenafil Citrate for Erectile Dysfunction

PubMed Central

Althof, Stanley E; O' Leary, Michael P; Cappelleri, Joseph C; Glina, Sidney; King, Rosie; Tseng, Li-Jung; Bowler, Jessica L

2006-01-01

BACKGROUND Men with erectile dysfunction (ED) often have low self-esteem, confidence, and sexual relationship satisfaction. OBJECTIVE We evaluated the impact of sildenafil citrate and its generalizability across cultures on self-esteem, confidence, and sexual relationship satisfaction in men with ED using the Self-Esteem And Relationship (SEAR) questionnaire. DESIGN Pooled analysis of 2 double-blind, placebo-controlled, flexible-dose trials of sildenafil with identical protocols: 1 was conducted in the United States and the other in Mexico, Brazil, Australia, and Japan. PATIENTS Men ≥18 years old with ED. MEASUREMENTS The impact of treatment on psychosocial factors associated with ED was determined by patient responses to the SEAR questionnaire. Erectile function was determined using the International Index of Erectile Function (IIEF) and a global efficacy question. Successful sexual intercourse attempts were derived from event logs of sexual activity. Treatment effect sizes were calculated for all study outcomes. RESULTS Compared with patients who received placebo (n = 274), patients who received sildenafil (n = 279) reported significantly greater improvements (P<.0001) in self-esteem, confidence, sexual relationship satisfaction, and in all sexual function domains of the IIEF. Treatment effect sizes were large (range, 0.7 to 1.2) for all SEAR components, and improvement in psychosocial measures showed moderate to high correlations (range, 0.50 to 0.83, P<.0001) with improvement in erectile function, percentage of successful intercourse attempts, and global efficacy. CONCLUSIONS In men with ED from 5 different nations, sildenafil produced substantial improvements in self-esteem, confidence, and sexual relationship satisfaction. Improvements in these psychosocial factors were observed crossculturally and correlated significantly and tangibly with improvements in erectile function. PMID:16836626

Superabsorbent nanocomposite synthesis of cellulose from rice husk grafted poly(acrylate acid-co-acrylamide)/bentonite

NASA Astrophysics Data System (ADS)

Helmiyati; Abbas, G. H.; Kurniawan, S.

2017-04-01

Superabsorbent nanocomposite synthesis of cellulose rice husk as the backbone with free radical polymerization method in copolymerization grafted with acrylic acid and acrylamide monomer. The cellulose was isolated from rice husk with mixture of toluene and ethanol and then hemicellulose and lignin were removed by using potassium hydroxide 4% and hydrogen peroxide 2%. The obtained cellulose rendement was 37.85%. The functional group of lignin analyzed by FTIR spectra was disappeared at wavenumber 1724 cm-1. Crystal size of the obtained isolated cellulose analyzed by XRD diffraction pattern was 34.6 nm, indicated the nanocrystal structure. Copolymerization was performed at temperature of 70°C with flow nitrogen gas. Initiator and crosslinking agent used were potassium persulfate and N‧N-methylene-bis-acrylamide. The swelling capacity of water and urea showed the results was quite satisfactory, the maximum swelling capacity in urea and water were 611.700 g/g and 451.303 g/g, respectively, and can be applied in agriculture to absorb water and urea fertilizer.

Why do gelatinized starch granules not dissolve completely? Roles for amylose, protein, and lipid in granule "ghost" integrity.

PubMed

Debet, Martine R; Gidley, Michael J

2007-06-13

After gelatinization in water, starch granules persist in swollen hydrated forms known as ghosts. Three potential mechanisms for ghost formation are tested. Proteins and lipids on the granule surface are found to be a determinant of ghost robustness, but not ghost formation. Proteins inside pre-made maize or wheat starch ghosts are degraded extensively by proteases without any apparent change in ghost properties, making an internal protein cross-linking mechanism unlikely. Waxy maize mutants with a range of amylose contents have ghost integrities that correlate with (low) apparent amylose levels. It is hypothesized that ghost formation is due to cross-linking of polysaccharide chains within swollen granules, most likely involving double helices formed from polymer chains that become free to move following heat-induced granule swelling. The size and robustness of granule ghosts is proposed to be determined by the relative rates of swelling and cross-linking, modulated by surface non-polysaccharide components.

Strain in shore fast ice due to incoming ocean waves and swell

NASA Astrophysics Data System (ADS)

Fox, Colin; Squire, Vernon A.

1991-03-01

Using a development from the theoretical model presented by Fox and Squire (1990), this paper investigates the strain field generated in shore fast ice by normally incident ocean waves and swell. After a brief description of the model and its convergence, normalized absolute strain (relative to a 1-m incident wave) is found as a function of distance from the ice edge for various wave periods, ice thicknesses, and water depths. The squared transfer function, giving the relative ability of incident waves of different periods to generate strain in the ice, is calculated, and its consequences are discussed. The ice is then forced with a Pierson-Moskowitz spectrum, and the consequent strain spectra are plotted as a function of penetration into the ice sheet. Finally, rms strain, computed as the incoherent sum of the strains resulting from energy in the open water spectrum, is found. The results have implications to the breakup of shore fast ice and hence to the floe size distribution of the marginal ice zone.

Enhanced structural stability of nanoporous zirconia under irradiation of He

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Tengfei; Huang, Xuejun; Wang, Chenxu

2012-01-01

This work reports a greatly enhanced tolerance for He irradiation-induced swelling in nanocrystalline zirconia film with interconnected nanoporous structure (hereinafter referred as to NC-C). Compared to bulk yttria-stabilized zirconia (YSZ) and another nanocrystalline zirconia film only with discrete nano voids (hereinafter referred as to NC-V), the NC-C film reveals good tolerance for irradiation of high-fluence He. No appreciable surface blistering can be found even at the highest fluence of 6 1017 cm2 in NCC film. From TEM analysis of as-irradiated samples, the enhanced tolerance for volume swelling in NCC film is attributed to the enhanced diffusion mechanism of deposited Hemore » via widely distributed nano channels. Furthermore, the growth of grain size is quite small for both nanocrystalline zirconia films after irradiation, which is ascribed to the decreasing of area of grain boundary due to loose structure and low energy of primary knock-on atoms for He ions.« less

Internal structure and swelling behaviour of in silico microgel particles

NASA Astrophysics Data System (ADS)

Rovigatti, Lorenzo; Gnan, Nicoletta; Zaccarelli, Emanuela

2018-01-01

Microgels are soft colloids that, by virtue of their polymeric nature, can react to external stimuli such as temperature or pH by changing their size. The resulting swelling/deswelling transition can be exploited in fundamental research as well as for many diverse practical applications, ranging from art restoration to medicine. Such an extraordinary versatility stems from the complex internal structure of the individual microgels, each of which is a crosslinked polymer network. Here we employ a recently-introduced computational method to generate realistic microgel configurations and look at their structural properties, both in real and Fourier space, for several temperatures across the volume phase transition as a function of the crosslinker concentration and of the confining radius employed during the ‘in-silico’ synthesis. We find that the chain-length distribution of the resulting networks can be analytically predicted by a simple theoretical argument. In addition, we find that our results are well-fitted to the fuzzy-sphere model, which correctly reproduces the density profile of the microgels under study.

Effect of freeze-thawing conditions for preparation of chitosan-poly (vinyl alcohol) hydrogels and drug release studies.

PubMed

Figueroa-Pizano, M D; Vélaz, I; Peñas, F J; Zavala-Rivera, P; Rosas-Durazo, A J; Maldonado-Arce, A D; Martínez-Barbosa, M E

2018-09-01

The freezing-thawing is an advantageous method to produce hydrogels without crosslinking agents. In this study chitosan-poly(vinyl alcohol) (CS-PVA) hydrogels were prepared by varying the freezing conditions and composition, which affect the final characteristics of the products. The swelling degree, morphology, porosity, and diflunisal drug loading, as well as the drug release profiles were evaluated. The hydrogel swelling ratio was found to be mainly affected by the CS content, the number of freezing cycles and the temperature. SEM micrographs and porosity data confirm that pore size increases with the chitosan content. However, the use of either lower temperatures or longer freezing times, results in higher porosity and smaller pores. The drug release times of the CS-PVA hydrogels were as long as 30 h, and according to the mathematical fitting, a simple diffusion mechanism dominates the process. Moreover, a mathematical model predicting the hydrogels physical and structural behavior is proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chitosan-hyaluronan/nano chondroitin sulfate ternary composite sponges for medical use.

PubMed

Anisha, B S; Sankar, Deepthi; Mohandas, Annapoorna; Chennazhi, K P; Nair, Shantikumar V; Jayakumar, R

2013-02-15

In this work chitosan-hyaluronan composite sponge incorporated with chondroitin sulfate nanoparticle (nCS) was developed. The fabrication of hydrogel was based on simple ionic cross-linking using EDC, followed by lyophilization to obtain the composite sponge. nCS suspension was characterized using DLS and SEM and showed a size range of 100-150 nm. The composite sponges were characterized using SEM, FT-IR and TG-DTA. Porosity, swelling, biodegradation, blood clotting and platelet activation of the prepared sponges were also evaluated. Nanocomposites showed a porosity of 67% and showed enhanced swelling and blood clotting ability. Cytocompatibility and cell adhesion studies of the sponges were done using human dermal fibroblast (HDF) cells and the nanocomposite sponges showed more than 90% viability. Nanocomposite sponges also showed enhanced proliferation of HDF cells within two days of study. These results indicated that this nanocomposite sponges would be a potential candidate for wound dressing. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tibioperoneal Trunk Aneurysm Resulting in Compartment Syndrome with Associated Aneurysms of the Popliteal and Dorsalis Pedis Arteries.

PubMed

Ventarola, Daniel J; Labropoulos, Nicos N; Landau, David S; Tassiopoulos, Apostolos K; Loh, Shang A

2016-08-01

True aneurysms of the tibioperoneal trunk are rare. Given the scarcity of reports, the clinical presentation and treatment is not well defined. This is a case report of a 50-year-old male patient presenting with severe lower extremity swelling and compartment syndrome with neurological compromise secondary to a tibioperoneal trunk aneurysm. He was also noted to have discrete ipsilateral popliteal and dorsalis pedis artery aneurysms. Given the location and size of the aneurysm, the severe leg swelling, and venous hypertension, aneurysmorrhaphy or aneurysm sac excision with arterial reconstruction was prohibitively dangerous. Thus, following fasciotomies, a hybrid repair utilizing a saphenous vein superficial femoral to anterior tibial artery bypass along with coil embolization of the aneurysm sac was performed. The patient recovered full function of his leg and follow-up computed tomography angiogram demonstrated thrombosis and regression of the aneurysm sac with a patent bypass. Copyright © 2016 Elsevier Inc. All rights reserved.

Laparoscopic management of urachal cyst associated with umbilical hernia.

PubMed

Gregory, G C; Vijay, R; Ligaj, M; Shiwani, M H

2011-02-01

The urachal cyst is a rare clinical entity of a urachal remnant. It is usually asymptomatic but can present with haematuria, tumour, urachal stone and infection. We present a case of a 63-year-old lady with a body mass index (BMI) of 49 who presented with a painful swelling in the umbilical region associated with an umbilical hernia. An ultrasound and computed tomography (CT) scan showed a suspected herniation of an umbilical remnant cyst through a paraumbilical defect. Laparoscopy confirmed the urachal cyst of 3 cm in size with a band connected with the cyst down to the urinary bladder associated with a 3-cm paraumbilical hernia. We removed the cyst and repaired the hernia laparoscopically uneventfully, after which her recovery was perfect. Radiological and laparoscopic pictures have not been reported in the English literature before. Although this condition is very rare, we suggest that it should be considered in the differential diagnosis of painful paraumbilical swelling. CT scanning and laparoscopy seems to be valuable, especially in obese patients.

Dissecting anode swelling in commercial lithium-ion batteries

NASA Astrophysics Data System (ADS)

Zhang, Ningxin; Tang, Huaqiong

2012-11-01

An innovative method is applied to investigate anode swelling during electrochemical processes in commercial lithium-ion batteries. Cathode surface is partially covered with a piece of paste to block the transportation of lithium ion from active material during charging/discharging, and the corresponding part on the anode film shows no formation of Li-graphite compounds during different electrochemical processes, which is confirmed by XRD analysis. The increases of anode thickness within and outside lithiated zone are measured, and defined as electrochemical swelling and physical swelling respectively. The microscopic lattice expansion of graphite due to lithiation process correlates to mesoscopic electrochemical swelling synchronically, while physical swelling tends to decrease steadily with time. The relationship among the microscopic stress due to lithium-ion intercalation, the mesoscopic stress resulting in anode swelling, and the macroscopic rippling of pouch cell after a large number of cycle test, is analyzed and correlated in terms of stress evolution across different scales, and suggestions for solving anode swelling are provided.

Effect of synthesis parameters on polymethacrylic acid xerogel structures and equilibrium swelling

NASA Astrophysics Data System (ADS)

Panić, V.; Jovanović, J.; Adnadjević, B.; Velicković, S.

2009-09-01

Hydrogels based on crosslinked polymethacrylic acid were synthesized via free-radical polymerization in aqueous solution, using N,N'-methylene bisacrylamide as a crosslinking agent and 2,2'-azobis-[2-(2-imidazolin-2-yl)propane] dihydrochloride as an initiator. The influence of the reaction parameters (the neutralization degree of methacrylic acid and the initial monomer concentration) on the equilibrium swelling degree, the swelling kinetic parameters and the basic structural properties of xerogels was investigated. The change of synthesis parameters leads to the change of the basic structural parameters of xerogel, as well as the equilibrium swelling degree and the initial swelling rate of the hydrogels. It is found that there are power form relationships between the equilibrium swelling degree, the initial swelling rate and the structural xerogel’s properties and the change of the neutralization degree of monomer, i.e. the monomer concentration. The examined correlations proved that the crosslinking density is the crucial parameter which determines all the other investigated structural and swelling parameters.

Dimensional stability and anisotropy of SiC and SiC-based composites in transition swelling regime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katoh, Yutai; Koyanagi, Takaaki; McDuffee, Joel L.

Swelling, or volumetric expansion, is an inevitable consequence of the atomic displacement damage in crystalline silicon carbide (SiC) caused by energetic neutron irradiation. Because of its steep temperature and dose dependence, understanding swelling is essential for designing SiC-based components for nuclear applications. Here in this study, swelling behaviors of monolithic CVD SiC and nuclear grade SiC fiber – SiC matrix (SiC/SiC) composites were accurately determined, supported by the irradiation temperature determination for individual samples, following neutron irradiation within the lower transition swelling temperature regime. Slightly anisotropic swelling behaviors were found for the SiC/SiC samples and attributed primarily to the combinedmore » effects of the pre-existing microcracking, fiber architecture, and specimen dimension. A semi-empirical model of SiC swelling was calibrated and presented. Finally, implications of the refined model to selected swelling-related issues for SiC-based nuclar reactor components are discussed.« less

Dimensional stability and anisotropy of SiC and SiC-based composites in transition swelling regime

DOE PAGES

Katoh, Yutai; Koyanagi, Takaaki; McDuffee, Joel L.; ...

2017-12-08

Swelling, or volumetric expansion, is an inevitable consequence of the atomic displacement damage in crystalline silicon carbide (SiC) caused by energetic neutron irradiation. Because of its steep temperature and dose dependence, understanding swelling is essential for designing SiC-based components for nuclear applications. Here in this study, swelling behaviors of monolithic CVD SiC and nuclear grade SiC fiber – SiC matrix (SiC/SiC) composites were accurately determined, supported by the irradiation temperature determination for individual samples, following neutron irradiation within the lower transition swelling temperature regime. Slightly anisotropic swelling behaviors were found for the SiC/SiC samples and attributed primarily to the combinedmore » effects of the pre-existing microcracking, fiber architecture, and specimen dimension. A semi-empirical model of SiC swelling was calibrated and presented. Finally, implications of the refined model to selected swelling-related issues for SiC-based nuclar reactor components are discussed.« less

Protein kinase C enhances the swelling-induced chloride current in human atrial myocytes.

PubMed

Li, Ye-Tao; Du, Xin-Ling

2016-06-01

Swelling-activated chloride currents (ICl.swell) are thought to play a role in several physiologic and pathophysiologic processes and thus represent a target for therapeutic approaches. However, the mechanism of ICl.swell regulation remains unclear. In this study, we used the whole-cell patch-clamp technique to examine the role of protein kinase C (PKC) in the regulation of ICl.swell in human atrial myocytes. Atrial myocytes were isolated from the right atrial appendages of patients undergoing coronary artery bypass and enzymatically dissociated. ICl.swell was evoked in hypotonic solution and recorded using the whole-cell patch-clamp technique. The PKC agonist phorbol dibutyrate (PDBu) enhanced ICl.swell in a concentration-dependent manner, which was reversed in isotonic solution and by a chloride current inhibitor, 9-anthracenecarboxylicacid. Furthermore, the PKC inhibitor bis-indolylmaleimide attenuated the effect and 4α-PDBu, an inactive PDBu analog, had no effect on ICl.swell. These results, obtained using the whole-cell patch-clamp technique, demonstrate the ability of PKC to activate ICl,swell in human atrial myocytes. This observation was consistent with a previous study using a single-channel patch-clamp technique, but differed from some findings in other species.

No evidence that sex and transposable elements drive genome size variation in evening primroses.

PubMed

Ågren, J Arvid; Greiner, Stephan; Johnson, Marc T J; Wright, Stephen I

2015-04-01

Genome size varies dramatically across species, but despite an abundance of attention there is little agreement on the relative contributions of selective and neutral processes in governing this variation. The rate of sex can potentially play an important role in genome size evolution because of its effect on the efficacy of selection and transmission of transposable elements (TEs). Here, we used a phylogenetic comparative approach and whole genome sequencing to investigate the contribution of sex and TE content to genome size variation in the evening primrose (Oenothera) genus. We determined genome size using flow cytometry for 30 species that vary in genetic system and find that variation in sexual/asexual reproduction cannot explain the almost twofold variation in genome size. Moreover, using whole genome sequences of three species of varying genome sizes and reproductive system, we found that genome size was not associated with TE abundance; instead the larger genomes had a higher abundance of simple sequence repeats. Although it has long been clear that sexual reproduction may affect various aspects of genome evolution in general and TE evolution in particular, it does not appear to have played a major role in genome size evolution in the evening primroses. © 2015 The Author(s).

Brain anti-cytoxic edema agents.

PubMed

Kimelberg, H K; Barron, K D; Bourke, R S; Nelson, L R; Cragoe, E J

1990-01-01

The work described in this chapter has indicated that improved outcome from an experimental head injury model can be achieved by drugs which are non-diuretic derivatives of loop diuretics, namely indanyl and fluorenyl compounds which are derivatives of ethacrynic acid. These drugs were originally identified by us on the basis of their efficacy in inhibiting [K+]-stimulated, HCO3(-)-dependent swelling of brain cerebrocortical slices. Swelling of glial cells (astrocytes) has long been known to be associated with such slice swelling and astrocyte swelling is a major locus of cytotoxic or cellular brain edema. Qualitative and quantitative electron microscope studies have shown that L644,711, a particularly effective member of the fluorenyl class of drugs, inhibits astrocytic swelling associated with an experimental animal head injury model. We have suggested that astrocytic swelling in pathological states may be partly due to activation of Cl-/HCO3- and Na+/H+ exchange systems driven by increased astrocytic intracellular hydration of CO2, and recent work has indeed shown that the ability of the indanyl and fluorenyl drugs to inhibit brain slice swelling and protect against head injury correlates closely with their ability to inhibit Cl-/HCO3- exchange. All these data suggest that astrocytic swelling, which seems to precede neuronal degeneration and breakdown of the blood-brain barrier, is deleterious and that prevention of such swelling can lead to effective therapy. We have used primary astrocytic cultures to explore reasons why astrocytic swelling could be harmful. Exposing such astrocytes to hypotonic medium causes rapid swelling with a slower return to normal volume in the continued presence of hypotonic medium, a process known as regulatory volume decrease or RVD. Such RVD is associated with marked release of several amino acids, including L-glutamate. L644,711 and other Cl-/HCO3- transport inhibitors such as SITS and furosemide, but not the selective Na+ + K+ + 2Cl- co-transport inhibitor bumetanide, inhibit such swelling-induced release of L-glutamate. Thus, L644,711 and other drugs may be effective in promoting recovery from head injury and other pathological states in which astrocytic swelling occurs either by initially preventing the swelling or inhibiting the release of excitotoxic excitatory amino acids if swelling does occur, perhaps depending at what time the drug is given.

Male vulnerability explains the occurrence of sexual cannibalism in a moderately sexually dimorphic wolf spider.

PubMed

Fernández-Montraveta, Carmen; González, José Miguel; Cuadrado, Mariano

2014-06-01

Sexual cannibalism is a widespread phenomenon among a few animal taxa. Its occurrence is interpreted as female and/or male optimal reproductive decisions or as a non-adaptive side effect of selection for efficiently foraging females. In spite of the amount of research addressed at understanding its evolutionary origins, we lack accurate information about the proximate causes of sexual cannibalism. In a moderately sexually dimorphic wolf spider (Hogna radiata, Araneae, Lycosidae) we assessed the factors mediating the occurrence of sexual cannibalism and its fitness benefits to females. Sexual cannibalism was a rather common outcome of laboratory mating interactions, occurring in more than a quarter percent of courtship interactions involving virgin females. Sexual cannibalism mostly followed mating. Occurrence of sexual cannibalism depended on male vulnerability to female attacks: relatively smaller males were at higher risk of being attacked and older males were less likely to avoid female attacks. Sexual cannibalism had direct and positive effects on female fitness, as sexually cannibalistic females exhibited increased fecundity irrespective of their size, condition and foraging rate. Male consumption was almost complete and represented a relevant food intake to females. We interpret sexual cannibalism as a strategic foraging decision for H. radiata females that adjust their aggressive behaviour towards males so as to limit its potential costs. Copyright © 2014 Elsevier B.V. All rights reserved.

Detecting self-ion irradiation-induced void swelling in pure copper using transient grating spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dennett, C. A.; So, K. P.; Kushima, A.

Irradiation-induced void swelling remains a major challenge to nuclear reactor operation. Swelling may take years to initiate and often results in rapid material property degradation once started. Alloy development for advanced nuclear systems will require rapid characterization of the swelling breakaway dose in new alloys, yet this capability does not yet exist. In this paper, we demonstrate that transient grating spectroscopy (TGS) can detect void swelling in single crystal copper via changes in surface acoustic wave (SAW) velocity. Scanning transmission electron microscopy (STEM) links the TGS-observed changes with void swelling-induced microstructural evolution. Finally, these results are considered in the contextmore » of previous work to suggest that in situ TGS will be able to rapidly determine when new bulk materials begin void swelling, shortening alloy development and testing times.« less

Detecting self-ion irradiation-induced void swelling in pure copper using transient grating spectroscopy

DOE PAGES

Dennett, C. A.; So, K. P.; Kushima, A.; ...

2017-12-20

Irradiation-induced void swelling remains a major challenge to nuclear reactor operation. Swelling may take years to initiate and often results in rapid material property degradation once started. Alloy development for advanced nuclear systems will require rapid characterization of the swelling breakaway dose in new alloys, yet this capability does not yet exist. In this paper, we demonstrate that transient grating spectroscopy (TGS) can detect void swelling in single crystal copper via changes in surface acoustic wave (SAW) velocity. Scanning transmission electron microscopy (STEM) links the TGS-observed changes with void swelling-induced microstructural evolution. Finally, these results are considered in the contextmore » of previous work to suggest that in situ TGS will be able to rapidly determine when new bulk materials begin void swelling, shortening alloy development and testing times.« less

RERTR-6 Irradiation Summary Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

D. M. Perez; M. A. Lillo; G. S. Chang

2011-12-01

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-6 was designed to evaluate several modified fuel designs that were proposed to address the possibility of breakaway swelling due to porosity within the (U. Mo) Al interaction product observed in the full-size plate tests performed in Russia and France1. The following report summarizes the life of the RERTR-6 experiment through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

Mucoadhesive Microparticles for Gastroretentive Delivery: Preparation, Biodistribution and Targeting Evaluation

PubMed Central

Hou, Jing-Yi; Gao, Li-Na; Meng, Fan-Yun; Cui, Yuan-Lu

2014-01-01

The aim of this research was to prepare and characterize alginate-chitosan mucoadhesive microparticles containing puerarin. The microparticles were prepared by an emulsification-internal gelatin method using a combination of chitosan and Ca2+ as cationic components and alginate as anions. Surface morphology, particle size, drug loading, encapsulation efficiency and swelling ratio, in vitro drug released, in vitro evaluation of mucoadhesiveness and Fluorescence imaging of the gastrointestinal tract were determined. After optimization of the formulation, the encapsulation efficiency was dramatically increased from 70.3% to 99.2%, and a highly swelling ratio was achieved with a change in particle size from 50.3 ± 11.2 μm to 124.7 ± 25.6 μm. In ethanol induced gastric ulcers, administration of puerarin mucoadhesive microparticles at doses of 150 mg/kg, 300 mg/kg, 450 mg/kg and 600 mg/kg body weight prior to ethanol ingestion significantly protected the stomach ulceration. Consequently, significant changes were observed in inflammatory cytokines, such as prostaglandin E2 (PGE2), tumor necrosis factor (TNF-α), interleukin 6 (IL-6), and interleukin1β (IL-1β), in stomach tissues compared with the ethanol control group. In conclusion, core-shell type pH-sensitive mucoadhesive microparticles loaded with puerarin could enhance puerarin bioavailability and have the potential to alleviate ethanol-mediated gastric ulcers. PMID:25470180

Incorporation of zinc oxide nanoparticles into chitosan-collagen 3D porous scaffolds: Effect on morphology, mechanical properties and cytocompatibility of 3D porous scaffolds.

PubMed

Ullah, Saleem; Zainol, Ismail; Idrus, Ruszymah Hj

2017-11-01

The zinc oxide nanoparticles (particles size <50nm) incorporated into chitosan-collagen 3D porous scaffolds and investigated the effect of zinc oxide nanoparticles incorporation on microstructure, mechanical properties, biodegradation and cytocompatibility of 3D porous scaffolds. The 0.5%, 1.0%, 2.0% and 4.0% zinc oxide nanoparticles chitosan-collagen 3D porous scaffolds were fabricated via freeze-drying technique. The zinc oxide nanoparticles incorporation effects consisting in chitosan-collagen 3D porous scaffolds were investigated by mechanical and swelling tests, and effect on the morphology of scaffolds examined microscopically. The biodegradation and cytocompatibility tests were used to investigate the effects of zinc oxide nanoparticles incorporation on the ability of scaffolds to use for tissue engineering application. The mean pore size and swelling ratio of scaffolds were decreased upon incorporation of zinc oxide nanoparticles however, the porosity, tensile modulus and biodegradation rate were increased upon incorporation of zinc oxide nanoparticles. In vitro culture of human fibroblasts and keratinocytes showed that the zinc oxide nanoparticles facilitated cell adhesion, proliferation and infiltration of chitosan-collagen 3D porous scaffolds. It was found that the zinc oxide nanoparticles incorporation enhanced porosity, tensile modulus and cytocompatibility of chitosan-collagen 3D porous scaffolds. Copyright © 2017 Elsevier B.V. All rights reserved.

Investigation of ITER candidate beryllium grades irradiated at high temperature

NASA Astrophysics Data System (ADS)

Kupriyanov, I. B.; Gorokhov, V. A.; Melder, R. R.; Ostrovsky, Z. E.; Gervash, A. A.

1998-10-01

Beryllium is one of the main candidate materials both for the neutron multiplier in a solid breeding blanket and for the plasma facing components. That is why the investigation of beryllium behaviour under the typical for fusion reactor loading, in particular under the neutron irradiation, is of a great importance. This paper presents some results of investigation of five beryllium grades (DshG-200, TR-30, TshG-56, TRR, TE-30, TIP-30) fabricated by VNIINM, Russia, and one (S-65) fabricated by Brush Wellman, USA. The average grain size of the investigated beryllium grades varied from 8 to 40 μm, beryllium oxide content was 0.7-3.2 wt.%, initial tensile strength 250-680 MPa. All the samples were irradiated in active zone of SM-3 reactor of 650-700°C up to the fast neutron fluence (5.5-6.2) × 10 21 cm -2 (2.7-3.0 dpa, helium content up to 1150 appm), E > 0.1 MeV. Irradiation swelling of the materials was revealed to be in the range of 0.3-1.7%. Beryllium grades TR-30 and TRR having the smallest grain size and highest beryllium oxide content, demonstrated minimal swelling, which did not exceed 0.3% at 700°C and fluence 5.5 × 10 21 cm -2. Mechanical properties and microstructure parameters measured before and after irradiation are also presented.

Development of repaglinide microspheres using novel acetylated starches of bitter and Chinese yams as polymers.

PubMed

Okunlola, Adenike; Adebayo, Amusa Sarafadeen; Adeyeye, Moji Christianah

2017-01-01

Tropical starches from Dioscorea dumetorum (bitter) and Dioscorea oppositifolia (Chinese) yams were acetylated with acetic anhydride in pyridine medium and utilized as polymers for the delivery of repaglinide in microsphere formulations in comparison to ethyl cellulose. Acetylated starches of bitter and Chinese yams with degrees of substitution of 2.56 and 2.70 respectively were obtained. Acetylation was confirmed by FTIR, 1 H NMR spectroscopy. A 3 2 factorial experimental design was performed using polymer type and drug-polymer ratio as independent variables. Particle size, swelling, entrapment and time for 50% drug release (t 50 ) were dependent variables. Contour plots showed the relationship between the independent factors and the response variables. All variables except swelling increased with drug: polymer ratio. Entrapment efficiency was generally in the rank of Bitter yam>Ethyl cellulose>Chinese yam. Repaglinide microspheres had size 50±4.00 to 350±18.10μm, entrapment efficiency 75.30±3.03 to 93.10±2.75% and t 50 3.20±0.42 to 7.20±0.55h. Bitter yam starch gave longer dissolution times than Chinese yam starch at all drug-polymer ratios. Drug release fitted Korsmeyer-Peppas and Hopfenberg models. Acetylated bitter and Chinese yam starches were found suitable as polymers to prolong release of repaglinide in microsphere formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Kinetic model for the mechanical response of suspensions of sponge-like particles.

PubMed

Hütter, Markus; Faber, Timo J; Wyss, Hans M

2012-01-01

A dynamic two-scale model is developed that describes the stationary and transient mechanical behavior of concentrated suspensions made of highly porous particles. Particularly, we are interested in particles that not only deform elastically, but also can swell or shrink by taking up or expelling the viscous solvent from their interior, leading to rate-dependent deformability of the particles. The fine level of the model describes the evolution of particle centers and their current sizes, while the shapes are at present not taken into account. The versatility of the model permits inclusion of density- and temperature-dependent particle interactions, and hydrodynamic interactions, as well as to implement insight into the mechanism of swelling and shrinking. The coarse level of the model is given in terms of macroscopic hydrodynamics. The two levels are mutually coupled, since the flow changes the particle configuration, while in turn the configuration gives rise to stress contributions, that eventually determine the macroscopic mechanical properties of the suspension. Using a thermodynamic procedure for the model development, it is demonstrated that the driving forces for position change and for size change are derived from the same potential energy. The model is translated into a form that is suitable for particle-based Brownian dynamics simulations for performing rheological tests. Various possibilities for connection with experiments, e.g. rheological and structural, are discussed.

The impact of health education transmitted via social media or text messaging on adolescent and young adult risky sexual behavior: a systematic review of the literature.

PubMed

Jones, Krista; Eathington, Patricia; Baldwin, Kathleen; Sipsma, Heather

2014-07-01

Despite the increased use of social media and text messaging among adolescents, it is unclear how effective education transmitted via these mechanisms is for reducing sexual risk behavior. Accordingly, we conducted a systematic review of the literature to examine the effectiveness of social media and text messaging interventions designed to increase sexually transmitted disease (STD) knowledge, increase screening/testing, decrease risky sexual behaviors, and reduce the incidence of STDs among young adults aged 15 through 24 years. Eleven studies met our inclusion criteria. Most of the included studies used a control group to explore intervention effects and included both young men and women. Sample sizes ranged from 32 to 7606 participants, and follow-up periods ranged between 4 weeks and 12 months. These studies provide preliminary evidence indicating that social media and text messaging can increase knowledge regarding the prevention of STDs. These interventions may also affect behavior, such as screening/testing for STDs, sexual risk behaviors, and STD acquisition, but the evidence for effect is weak. Many of these studies had several limitations that future research should address, including a reliance on self-reported data, small sample sizes, poor retention, low generalizability, and low analytic rigor. Additional research is needed to determine the most effective and engaging approaches for young men and women.

Why do female Callosobruchus maculatus kick their mates?

PubMed

van Lieshout, Emile; McNamara, Kathryn B; Simmons, Leigh W

2014-01-01

Sexual conflict is now recognised as an important driver of sexual trait evolution. However, due to their variable outcomes and effects on other fitness components, the detection of sexual conflicts on individual traits can be complicated. This difficulty is exemplified in the beetle Callosobruchus maculatus, where longer matings increase the size of nutritious ejaculates but simultaneously reduce female future receptivity. While previous studies show that females gain direct benefits from extended mating duration, females show conspicuous copulatory kicking behaviour, apparently to dislodge mating males prematurely. We explore the potential for sexual conflict by comparing several fitness components and remating propensity in pairs of full sibling females where each female mated with a male from an unrelated pair of full sibling males. For one female, matings were terminated at the onset of kicking, whereas the other's matings remained uninterrupted. While fecundity (number of eggs) was similar between treatments, uninterrupted matings enhanced adult offspring numbers and fractionally also longevity. However, females whose matings were interrupted at the onset of kicking exhibited an increased propensity to remate. Since polyandry can benefit female fitness in this species, we argue that kicking, rather than being maladaptive, may indicate that females prefer remating over increased ejaculate size. It may thus be difficult to assess the presence of sexual conflict over contested traits such as mating duration when females face a trade off between direct benefits gained from one mating and indirect benefits from additional matings.

Rapid loss of behavioral plasticity and immunocompetence under intense sexual selection.

PubMed

van Lieshout, Emile; McNamara, Kathryn B; Simmons, Leigh W

2014-09-01

Phenotypic plasticity allows animals to maximize fitness by conditionally expressing the phenotype best adapted to their environment. Although evidence for such adjustment in reproductive tactics is common, little is known about how phenotypic plasticity evolves in response to sexual selection. We examined the effect of sexual selection intensity on phenotypic plasticity in mating behavior using the beetle Callosobruchus maculatus. Male genital spines harm females during mating and females exhibit copulatory kicking, an apparent resistance trait aimed to dislodge mating males. After exposing individuals from male- and female-biased experimental evolution lines to male- and female-biased sociosexual environments, we examined behavioral plasticity in matings with standard partners. While females from female-biased lines kicked sooner after exposure to male-biased sociosexual contexts, in male-biased lines this plasticity was lost. Ejaculate size did not diverge in response to selection history, but males from both treatments exhibited plasticity consistent with sperm competition intensity models, reducing size as the number of competitors increased. Analysis of immunocompetence revealed reduced immunity in both sexes in male-biased lines, pointing to increased reproductive costs under high sexual selection. These results highlight how male and female reproductive strategies are shaped by interactions between phenotypically plastic and genetic mechanisms of sexual trait expression. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Does fluctuating asymmetry of antlers in white-tailed deer (Odocoileus virginianus) follow patterns predicted for sexually selected traits?

USGS Publications Warehouse

Ditchkoff, S.S.; Lochmiller, R.L.; Masters, R.E.; Starry, W.R.; Leslie, David M.

2001-01-01

Secondary sexual characters have been hypothesized to signal male quality and should demonstrate a negative relationship between the size of the trait and degree of fluctuating asymmetry because they are costly to produce. We collected morphometric and antler data from 439 white-tailed deer (Odocoileus virginianus) in Oklahoma, USA, in order to determine whether measures of antler asymmetry follow the patterns predicted for sexually selected characters. Relative fluctuating asymmetry was negatively related to antler size for all deer and within age groups up to five and a half years of age. We did not detect an association between asymmetry and antler size among deer that were six and a half years or older. When categorizing deer by antler size, we found that deer with small antlers (???33rd percentile) had greater levels of relative asymmetry than deer with large antlers (???67th percentile). The relative asymmetry of antlers was negatively related to age and was greatest in deer that were one and a half years old. Relative asymmetry was also negatively related to carcass mass, inside spread, skull length and body length. These data suggest that asymmetry in the antlers of white-tailed deer may be a reliable signal of quality and, as such, may be important in maintaining honesty in intrasexual advertisements during the breeding season.

Alternative life histories in the Atlantic salmon: genetic covariances within the sneaker sexual tactic in males.

PubMed

Páez, David James; Bernatchez, Louis; Dodson, Julian J

2011-07-22

Alternative reproductive tactics are ubiquitous in many species. Tactic expression often depends on whether an individual's condition surpasses thresholds that are responsible for activating particular developmental pathways. Two central goals in understanding the evolution of reproductive tactics are quantifying the extent to which thresholds are explained by additive genetic effects, and describing their covariation with condition-related traits. We monitored the development of early sexual maturation that leads to the sneaker reproductive tactic in Atlantic salmon (Salmo salar L.). We found evidence for additive genetic variance in the timing of sexual maturity (which is a measure of the surpassing of threshold values) and body-size traits. This suggests that selection can affect the patterns of sexual development by changing the timing of this event and/or body size. Significant levels of covariation between these traits also occurred, implying a potential for correlated responses to selection. Closer examination of genetic covariances suggests that the detected genetic variation is distributed along at least five directions of phenotypic variation. Our results show that the potential for evolution of the life-history traits constituting this reproductive phenotype is greatly influenced by their patterns of genetic covariance.

Alternative life histories in the Atlantic salmon: genetic covariances within the sneaker sexual tactic in males

PubMed Central

Páez, David James; Bernatchez, Louis; Dodson, Julian J.

2011-01-01

Alternative reproductive tactics are ubiquitous in many species. Tactic expression often depends on whether an individual's condition surpasses thresholds that are responsible for activating particular developmental pathways. Two central goals in understanding the evolution of reproductive tactics are quantifying the extent to which thresholds are explained by additive genetic effects, and describing their covariation with condition-related traits. We monitored the development of early sexual maturation that leads to the sneaker reproductive tactic in Atlantic salmon (Salmo salar L.). We found evidence for additive genetic variance in the timing of sexual maturity (which is a measure of the surpassing of threshold values) and body-size traits. This suggests that selection can affect the patterns of sexual development by changing the timing of this event and/or body size. Significant levels of covariation between these traits also occurred, implying a potential for correlated responses to selection. Closer examination of genetic covariances suggests that the detected genetic variation is distributed along at least five directions of phenotypic variation. Our results show that the potential for evolution of the life-history traits constituting this reproductive phenotype is greatly influenced by their patterns of genetic covariance. PMID:21177685

Does the timing of attainment of maturity influence sexual size dimorphism and adult sex ratio in turtles?

USGS Publications Warehouse

Lovich, Jeffrey E.; Gibbons, J. Whitfield; Agha, Mickey

2014-01-01

The attainment of sexual maturity has been shown to affect measures of sexual size dimorphism (SSD) and adult sex ratios in several groups of vertebrates. Using data for turtles, we tested the model that sex ratios are expected to be male-biased when females are larger than males and female-biased when males are larger than females because of the relationship of each with the attainment of maturity. Our model is based on the premise that the earlier-maturing sex remains smaller, on average throughout life, and predominates numerically unless the sexes are strongly affected by differential mortality, differential emigration, and immigration, or biased primary sex ratios. Based on data for 24 species in seven families, SSD and sex ratios were significantly negatively correlated for most analyses, even after the effect of phylogenetic bias was removed. The analyses provide support for the model that SSD and adult sex ratios are correlated in turtles as a result of simultaneous correlation of each with sexual differences in attainment of maturity (bimaturism). Environmental sex determination provides a possible mechanism for the phenomenon in turtles and some other organisms.

What puts them at risk? A cross-sectional case-control survey of demographic profile and sexual behavior of patients with sexually transmitted infections at a tertiary care center in North India.

PubMed

Raj, Rama; Gupta, Vishal; Pathak, Mona; Sreenivas, Vishnubhatla; Sood, Seema; Singh, Sarman; Verma, Kaushal K; Khanna, Neena; Das, Bimal K; Gupta, Somesh

2017-01-01

Sexually transmitted infections (STIs) are a major public health problem in developing nations. Identification of risk factors can help in formulating effective strategies against them. The present study was conducted in a tertiary care hospital in North India over 1 year to identify the risk factors associated with STIs. A questionnaire-based cross-sectional case-control survey was conducted where participants answered questions on demographic details, sexual behavior, and awareness of STIs. Cases were patients with STIs whereas controls were randomly selected from healthy individuals accompanying patients with nonvenereal complaints attending our hospital. There were 106 cases and 64 controls. STI patients had sexual debut 2 years before controls. A higher proportion of STI cases had lower education, multiple sexual partners, lived separately from their partner, had nonregular partners, had protected sex in the last month, had sex under influence of alcohol/illicit drugs, sex in unstructured settings, and engaged in transactional sex, in comparison to controls ( P < 0.05). More cases were aware of the symptoms/preventive measures of STIs ( P < 0.001). On multivariate analysis, multiple sexual partners, sex under influence of alcohol/illicit drugs with nonregular partner, protected sex in the last month, and knowledge of preventive measures were found to be statistically associated with STIs ( P < 0.05). Our study identifies risk-behavior patterns in patients with STIs, which should be modified to reduce the burden of these diseases. Increasing the knowledge about STIs in these patients can translate into more common condom usage that lends support for strengthening sexual health programs at grass-root levels. The small size of the study population could have led to decreased power of the study to detect differences between cases and controls. The external validity of our results needs to be tested in different population groups involving larger sample sizes.

The form of sexual selection arising from male-male competition depends on the presence of females in the social environment.

PubMed

Procter, D S; Moore, A J; Miller, C W

2012-05-01

Sexual selection arises from social interactions, and if social environments vary so too should sexual selection. For example, male-male competition often occurs either in the presence or in the absence of females, and such changes in the social environment could affect the form and strength of sexual selection. Here we examine how the presence of a female influences selection arising from male-male competition in a leaf-footed cactus bug, Narnia femorata, which has a resource defence mating system. Males compete for territories on cacti because females lay eggs on the cactus plants. Females are not always present when this competition first occurs; however, the presence or absence of the female matters. We found that both the form and strength of selection on male traits, those traits that influenced success in intrasexual competition, depended on the social context. When a female was not present, male size and the area of the sexually dimorphic hind legs was only marginally important to winning a contest. However, males with larger overall size and leg area were more likely to win in the presence of a female. There was also positive quadratic selection on these traits when a female was present with both the largest and the smallest males winning. The implication is unexpected alternative strategies when females are present. Our results support the notion that sexual selection should be studied under all relevant social contexts. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Psychiatric disorders in single and multiple sexual murderers.

PubMed

Hill, Andreas; Habermann, Niels; Berner, Wolfgang; Briken, Peer

2007-01-01

Sexual homicides - and particularly offenders with multiple victims - receive much attention in the general public as well as among forensic experts. The aim of this study was to assess psychiatric disorders in a large sample of sexual murderers and to identify disorders related to multiple sexual homicides. Psychiatric court reports from 20 German forensic psychiatrists on 166 men who had committed a sexual homicide were evaluated for psychiatric disorders according to DSM-IV, including standardized instruments for personality disorders (criteria from the Structured Clinical Interview) and psychopathy (Psychopathy Checklist-Revised). Offenders with a single sexual homicide victim (n = 130) were compared to those with multiple victims (n = 36). High lifetime prevalence rates were found for substance abuse or dependence, paraphilias (especially sexual sadism), sexual dysfunctions and personality disorders (especially antisocial, borderline, sadistic and schizoid). In the multiple sexual murderer group sexual sadism, voyeurism, sadistic, antisocial and schizoid personality disorders were more frequent than in the single-victim group; none of the multiple offenders was diagnosed with a mood disorder. Multiple sexual murderers are characterized by disorders in three major psychopathological domains: sexual as well as 'character' sadism, antisociality and schizoid personality. A thorough diagnostic evaluation of Axis I as well as Axis II disorders should be part of risk assessments in sexual homicide perpetrators. Although the study was a retrospective investigation on psychiatric court reports, the size of the sample and consistency with results from previous studies give confidence that the identified group differences are unlikely to be due to methodological limitations.

The Time Course of Knee Swelling Post Total Knee Arthroplasty and Its Associations with Quadriceps Strength and Gait Speed.

PubMed

Pua, Yong-Hao

2015-07-01

This study examines the time course of knee swelling post total knee arthroplasty (TKA) and its associations with quadriceps strength and gait speed. Eighty-five patients with unilateral TKA participated. Preoperatively and on post-operative days (PODs) 1, 4, 14, and 90, knee swelling was measured using bioimpedance spectrometry. Preoperatively and on PODs 14 and 90, quadriceps strength was measured using isokinetic dynamometry while fast gait speed was measured using the timed 10-meter walk. On POD1, knee swelling increased ~35% from preoperative levels after which, knee swelling reduced but remained at ~11% above preoperative levels on POD90. In longitudinal, multivariable analyses, knee swelling was associated with quadriceps weakness (P<0.01) and slower gait speed (P=0.03). Interventions to reduce post-TKA knee swelling may be indicated to improve quadriceps strength and gait speed. Copyright © 2015 Elsevier Inc. All rights reserved.

Swelling soils in the road structures

NASA Astrophysics Data System (ADS)

Pruška, Jan; Šedivý, Miroslav

2017-09-01

There are frequent problems with the soil swelling in the road construction in the past time. This phenomenon is known for decades. This situation is notably given by insufficient knowledge of this problem and difficulties with input parameters describing the swelling process. The paper in the first part proposed regression relations to predict swelling pressure, time of swelling and swelling strain for different initial water contents for soils and improvement soils. The relations were developed by using artificial neural network and QCExpert Professional software (on the data from site investigations by GeoTec-GS, a.s. and experimental data from CTU in Prague). The advantage of the relations is based on using the results of the basic soil tests (plasticity index, consistency index and colloidal activity) as input parameters. The authors inform the technical public with their current knowledge of the problems with the soil swelling on the motorway in the second part of the paper.

Extracorporeal shock wave therapy in Peyronie's disease: results of a placebo-controlled, prospective, randomized, single-blind study.

PubMed

Hatzichristodoulou, Georgios; Meisner, Christoph; Gschwend, Jürgen E; Stenzl, Arnulf; Lahme, Sven

2013-11-01

Extracorporeal shock wave therapy (ESWT) for treatment of Peyronie's disease (PD) is controversial. To study the efficacy of ESWT by a placebo-controlled, randomized trial. Patients with PD (n=102) were randomly assigned (n=51) to each group (ESWT or placebo). All patients were given 6 weekly treatments. Patients in the ESWT-group received 2,000 shock waves per session, using the Piezoson 100 lithotripter (Richard Wolf, Knittlingen, Germany). Patients in the placebo-group were treated with interposition of a plastic membrane, which prevented any transmission of shock waves. Primary end point was decrease of pain between baseline and after 4 weeks follow-up. Secondary end points were changes in deviation, plaque size, and sexual function. Pain was assessed by a visual analog scale. Deviation was measured by a goniometer after artificial erection using Alprostadil (Viridal®, Schwarz Pharma, Monheim, Germany). Plaque size was measured with a ruler and sexual function assessed by a scale regarding the ability to perform sexual intercourse. Overall, only 45 patients experienced pain at baseline. In the subgroup analysis of these patients, pain decreased in 17/20 (85.0%) patients in the ESWT group and 12/25 (48.0%) patients in the placebo group (P=0.013, relative risk [RR]=0.29, 95% confidence interval: 0.09-0.87). Penile deviation was not reduced by ESWT (P=0.66) but worsened in 20/50 (40%) and 12/49 (24.5%) patients of the ESWT and placebo-group, respectively (P=0.133). Plaque size reduction was not different between the two groups (P=0.33). Additional, plaque size increased in five patients (10.9%) of the ESWT group only. An improvement in sexual function could not be verified (P=0.126, RR=0.46). Despite some potential benefit of ESWT in regard to pain reduction, it should be emphasized that pain usually resolves spontaneously with time. Given this and the fact that deviation may worsen with ESWT, this treatment cannot be recommended. © 2013 International Society for Sexual Medicine.

Phenotypic integration mediated by hormones: associations among digit ratios, body size and testosterone during tadpole development.

PubMed

Lofeu, Leandro; Brandt, Renata; Kohlsdorf, Tiana

2017-08-02

Developmental associations often explain phenotypic integration. The intersected hormonal regulation of ontogenetic processes fosters predictions of steroid-mediated phenotypic integration among sexually dimorphic traits, a statement defied by associations between classical dimorphism predictors (e.g. body size) and traits that apparently lack sex-specific functions (e.g. ratios between the lengths of Digits II and IV - 2D:4D). Developmental bases of female-biased 2D:4D have been identified, but these remain unclear for taxa presenting male-biased 2D:4D (e.g. anura). Here we propose two alternative hypotheses to investigate evolution of male-biased 2D:4D associated with sexually dimorphic body size using Leptodactylus frogs: I)'hypothesis of sex-specific digit responses' - Digit IV would be reactive to testosterone but exhibit responses in the opposite direction of those observed in female-biased 2D:4D lineages, so that Digit IV turns shorter in males; II) 'hypothesis of identity of the dimorphic digit'- Digit II would be the dimorphic digit. We compiled the following databases using Leptodactylus frogs: 1) adults of two species from natural populations and 2) testosterone-treated L. fuscus at post-metamorphic stage. Studied traits seem monomorphic in L. fuscus; L. podicipinus exhibits male-biased 2D:4D. When present, 2D:4D dimorphism was male-biased and associated with dimorphic body size; sex differences resided on Digit II instead of IV, corroborating our 'hypothesis of identity of the dimorphic digit'. Developmental steroid roles were validated: testosterone-treated L. fuscus frogs were smaller and exhibited masculinized 2D:4D, and Digit II was the digit that responded to testosterone. We propose a model where evolution of sexual dimorphism in 2D:4D first originates from the advent, in a given digit, of increased tissue sensitivity to steroids. Phenotypic integration with other sexually dimorphic traits would then occur through multi-trait hormonal effects during development. Such process of phenotypic integration seems fitness-independent in its origin and might explain several cases of steroid-mediated integration among sexually dimorphic traits.

Molecular Dynamics Study of Crystalline Swelling of Montmorillonite as Affected by Interlayer Cation Hydration

NASA Astrophysics Data System (ADS)

Li, Hongliang; Song, Shaoxian; Dong, Xianshu; Min, Fanfei; Zhao, Yunliang; Peng, Chenliang; Nahmad, Yuri

2018-04-01

Swelling of montmorillonite (Mt) is an important factor for many industrial applications. In this study, crystalline swelling of alkali-metal- and alkaline-earth-metal-Mt has been studied through energy optimization and molecular dynamics simulations using the clay force field by Materials Studio 8.0. The delamination and exfoliation of Mt are primarily realized by crystalline swelling caused by the enhanced interlayer cation hydration. The initial position of the interlayer cations and water molecules is the dominated factor for the accuracy of the Mt simulations. Crystalline swelling can be carried out in alkali-metal-Mt and Mg-Mt but with difficulty in Ca-Mt, Sr-Mt and Ba-Mt. The crystalline swelling capacity values are in the order Na-Mt > K-Mt > Cs-Mt > Mg-Mt. This order of crystalline swelling of Mt in the same group can be attributed to the differences between the interlayer cation hydration strengths. In addition, the differences in the crystalline swelling between the alkali-metal-Mt and alkaline-earth-metal-Mt can be primarily attributed to the valence of the interlayer cations.

Propagation Route and Speed of Swell in the Indian Ocean

NASA Astrophysics Data System (ADS)

Zheng, C. W.; Li, C. Y.; Pan, J.

2018-01-01

The characteristics of swell propagation play an important role in the forecasting of ocean waves as well as on research on global climate change, wave energy development, and disaster prevention and reduction. To reveal the propagation routes, terminal targets and speeds of swells that originate from the southern Indian Ocean westerly (SIOW), an intraseasonal swell index (SI) was defined based on the 45 year (September 1957 to August 2002) ERA-40 wave reanalysis data product from the European Center for Medium-Range Weather Forecasts (ECMWF). The results show that the main body of the SIOW-related swells typically spread to the waters off Sri Lanka and Christmas Island, while the branches spread to the Arabian Sea and other waters. The propagation speeds of swells originated in the SIOW were fastest in May and August, followed by November, and were slowest in February. Swells usually required 4-6 days to propagate from the western part of the SIOW to the waters off Sri Lanka and Christmas Island, whereas swells usually required 2-4 days to propagate from the eastern part of the SIOW to the waters off Christmas Island.

Differential investment in pre- vs. post-copulatory sexual selection reinforces a cross-continental reversal of sexual size dimorphism in Sepsis punctum (Diptera: Sepsidae).

PubMed

Puniamoorthy, Nalini; Blanckenhorn, W U; Schäfer, M A

2012-11-01

Theory predicts that males have a limited amount of resources to invest in reproduction, suggesting a trade-off between traits that enhance mate acquisition and those that enhance fertilization success. Here, we investigate the relationship between pre- and post-copulatory investment by comparing the mating behaviour and reproductive morphology of four European and five North American populations of the dung fly Sepsis punctum (Diptera) that display a reversal of sexual size dimorphism (SSD). We show that the geographic reversal in SSD between the continents (male biased in Europe, female biased in North America) is accompanied by differential investment in pre- vs. post-copulatory traits. We find higher remating rates in European populations, where larger males acquire more matings and consequently have evolved relatively larger testes and steeper hyper-allometry with body size. American populations, in sharp contrast, display much reduced, if any, effect of body size on those traits. Instead, North American males demonstrate an increased investment in mate acquisition prior to copulation, with more mounting attempts and a distinctive abdominal courtship display that is completely absent in Europe. When controlling for body size, relative female spermathecal size is similar on both continents, so we find no direct evidence for the co-evolution of male and female internal reproductive morphology. By comparing allopatric populations of the same species that apparently have evolved different mating systems and consequently SSD, we thus indirectly demonstrate differential investment in pre- vs. post-copulatory mechanisms increasing reproductive success. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Discovery of the Largest Orbweaving Spider Species: The Evolution of Gigantism in Nephila

PubMed Central

Kuntner, Matjaž; Coddington, Jonathan A.

2009-01-01

Background More than 41,000 spider species are known with about 400–500 added each year, but for some well-known groups, such as the giant golden orbweavers, Nephila, the last valid described species dates from the 19th century. Nephila are renowned for being the largest web-spinning spiders, making the largest orb webs, and are model organisms for the study of extreme sexual size dimorphism (SSD) and sexual biology. Here, we report on the discovery of a new, giant Nephila species from Africa and Madagascar, and review size evolution and SSD in Nephilidae. Methodology We formally describe N. komaci sp. nov., the largest web spinning species known, and place the species in phylogenetic context to reconstruct the evolution of mean size (via squared change parsimony). We then test female and male mean size correlation using phylogenetically independent contrasts, and simulate nephilid body size evolution using Monte Carlo statistics. Conclusions Nephila females increased in size almost monotonically to establish a mostly African clade of true giants. In contrast, Nephila male size is effectively decoupled and hovers around values roughly one fifth of female size. Although N. komaci females are the largest Nephila yet discovered, the males are also large and thus their SSD is not exceptional. PMID:19844575

Discovery of the largest orbweaving spider species: the evolution of gigantism in Nephila.

PubMed

Kuntner, Matjaz; Coddington, Jonathan A

2009-10-21

More than 41,000 spider species are known with about 400-500 added each year, but for some well-known groups, such as the giant golden orbweavers, Nephila, the last valid described species dates from the 19(th) century. Nephila are renowned for being the largest web-spinning spiders, making the largest orb webs, and are model organisms for the study of extreme sexual size dimorphism (SSD) and sexual biology. Here, we report on the discovery of a new, giant Nephila species from Africa and Madagascar, and review size evolution and SSD in Nephilidae. We formally describe N. komaci sp. nov., the largest web spinning species known, and place the species in phylogenetic context to reconstruct the evolution of mean size (via squared change parsimony). We then test female and male mean size correlation using phylogenetically independent contrasts, and simulate nephilid body size evolution using Monte Carlo statistics. Nephila females increased in size almost monotonically to establish a mostly African clade of true giants. In contrast, Nephila male size is effectively decoupled and hovers around values roughly one fifth of female size. Although N. komaci females are the largest Nephila yet discovered, the males are also large and thus their SSD is not exceptional.

Antisense oligodeoxynucleotide inhibition of a swelling-activated cation channel in osteoblast-like osteosarcoma cells

NASA Technical Reports Server (NTRS)

Duncan, R. L.; Kizer, N.; Barry, E. L.; Friedman, P. A.; Hruska, K. A.

1996-01-01

By patch-clamp analysis, we have shown that chronic, intermittent mechanical strain (CMS) increases the activity of stretch-activated cation channels of osteoblast-like UMR-106.01 cells. CMS also produces a swelling-activated whole-cell conductance (Gm) regulated by varying strain levels. We questioned whether the swelling-activated conductance was produced by stretch-activated cation channel activity. We have identified a gene involved in the increase in conductance by using antisense oligodeoxynucleotides (ODN) derived from the alpha 1-subunit genes of calcium channels found in UMR-106.01 cells (alpha1S, alpha1C, and alpha1D). We demonstrate that alpha 1C antisense ODNs abolish the increase in Gm in response to hypotonic swelling following CMS. Antisense ODNs to alpha1S and alpha1D, sense ODNs to alpha1C, and sham permeabilization had no effect on the conductance increase. In addition, during cell-attached patch-clamp studies, antisense ODNs to alpha1c completely blocked the swelling-activated and stretch-activated nonselective cation channel response to strain. Antisense ODNs to alpha1S treatment produced no effect on either swelling-activated or stretch-activated cation channel activity. There were differences in the stretch-activated and swelling-activated cation channel activity, but whether they represent different channels could not be determined from our data. Our data indicate that the alpha1C gene product is involved in the Gm and the activation of the swelling-activated cation channels induced by CMS. The possibility that swelling-activated cation channel genes are members of the calcium channel superfamily exists, but if alpha1c is not the swelling-activated cation channel itself, then its expression is required for induction of swelling-activated cation channel activity by CMS.

Monitoring austral and cyclonic swells in the "Iles Eparses" (Mozambique channel) from microseismic noise

NASA Astrophysics Data System (ADS)

Barruol, Guilhem; Davy, Céline; Fontaine, Fabrice R.; Schlindwein, V.; Sigloch, K.

2016-04-01

We deployed five broadband three-components seismic stations in the Iles Eparses in the south-west Indian Ocean and on Mayotte Island, between April 2011 and January 2014. These small and remote oceanic islands suffer the effects of strong ocean swells that affect their coastal environments but most islands are not instrumented by wave gauges to characterize the swells. However, wave action on the coast causes high levels of ground vibrations in the solid earth, so-called microseismic noise. We use this link between the solid earth and ocean wave activity to quantify the swells locally. Spectral analyses of the continuous seismic data show clear peaks in the 0.05-0.10 Hz frequency band (periods between 10 and 20 s), corresponding to the ocean wave periods of the local swells. We analyze an example of austral swell occurring in August 2013 and a cyclonic event (Felleng) that developed in January 2013, and quantify the ground motion at each station induced by these events. In both cases, we find a linear polarization in the horizontal plane with microseismic amplitude directly correlated to the swell height (as predicted by the global swell model WaveWatchIII), and a direction of polarization close to the predicted swell propagation direction. Although this analysis has not been performed in real time, it demonstrates that terrestrial seismic stations can be efficiently used as wave gauges, and are particularly well suited for quantifying extreme swell events. This approach may therefore provide useful and cheaper alternatives to wave buoys for monitoring swells and the related environmental processes such as beach erosion or coral reef damages.