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1.
Mil Med ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38966901

ABSTRACT

INTRODUCTION: Barriers to seeking infertility care for lesbian, gay, bisexual, transgender, intersex, queer/questioning, and asexual (LGBTIQA+) individuals are well documented in the literature. However, little is known about military LGBTIQA+ service members seeking infertility care within the Military Health System. Approximately 6.1% of active duty U.S. service members across all branches identify as LGBTIQA+, which underscores the need for a deeper understanding of the needs of this community to support and retain service members. We therefore sought to describe the lived experiences of lesbian and gay cisgender service members in building their families in order to understand their family-building desires and potential barriers to seeking infertility care. MATERIALS AND METHODS: We developed a survey to investigate the impact of military service on family planning. After Institutional Review Board approval, we distributed the survey throughout Walter Reed National Military Medical Center's obstetrics and gynecology clinic and posted the survey on multiple open and closed social media pages for LGBTIQA+ service members. We reported descriptive statistics of our survey and compared binary variables using the Fisher exact test. Following completion of this survey, participants could self-select to participate in semi-structured interviews. RESULTS: Sixty-eight respondents completed our survey and self-identified as either cis-male (n = 28) or cis-female (n = 40). Most respondents (67.9% cis-males, 92.5% cis-females) plan to build their families during their military commitment; however, approximately half (50.0% cis-male, 42.5% cis-female) reported a lack of support in this endeavor. Many respondents were unaware of resources that would assist in the pursuit of donor egg, donor sperm, or surrogacy (78.6% cis-males, 50.0% cis-females). Thirty-six participants elected to complete a follow-up interview. After coding the interviews, 5 themes emerged: (1) barriers to initiating care; (2) institutional barriers within the military; (3) political barriers; (4) knowledge sharing; and (5) implicit and explicit bias. CONCLUSIONS: Our results suggest significant barriers to LGBTIQA+ service members seeking infertility care. Overall, LGBTIQA+ service members did not feel supported by the military in building their families. Although the military has expanded access to infertility services, efforts to raise awareness and build support for LGBTIQA+ service members are warranted.

3.
Clin Obstet Gynecol ; 64(1): 48-54, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33337740

ABSTRACT

Polycystic ovarian syndrome (PCOS) presents as a constellation of clinical manifestations that can be varied among patients; however, the hormonal derangement associated with PCOS is uniformly characterized by excess androgens and abnormal insulin activity. The alteration in the normal hormonal milieu in these patients and subsequently during their pregnancies is theorized to alter the normal development of the fetus. This in utero exposure and its relationship with behavioral development, metabolic disease, and reproductive outcomes in male and female offspring of mothers with PCOS are under investigation and remains controversial.


Subject(s)
Polycystic Ovary Syndrome , Androgens , Female , Humans , Male , Pregnancy
4.
Obstet Gynecol ; 136(5): 1059-1060, 2020 11.
Article in English | MEDLINE | ID: mdl-33030864
5.
Econ Lett ; 195: 109416, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32834238

ABSTRACT

The recent spread of COVID-19 has led to the worst economic crisis since the 1930s. To boost demand after the crisis, direct monetary transfers to households are being discussed. Using novel microdata from the Eurosystem Household Finance and Consumption Survey (HFCS), we study how much of such a transfer households would actually spend. We do so by exploiting the unique opportunity that the new wave of the survey included an experimental question to calculate the marginal propensity to consume from hypothetical windfall gains. Our results show that households on average spend between about 33% (the Netherlands) and 57% (Lithuania) of such a transfer. In all countries, answers are clustered at spending nothing, spending 50% and spending everything. Marginal propensities to consume decrease with income but are not as clearly related to wealth.

6.
Animals (Basel) ; 10(2)2020 Feb 21.
Article in English | MEDLINE | ID: mdl-32098237

ABSTRACT

Castration of male pigs without anesthesia is a significant welfare issue. Improvac®, a GnRH vaccine induces an endogenous immune response leading to a decrease in testicular steroids. Consequences of different vaccination schemes on testicular function and carcass quality were evaluated in immunocastrated boars (IC), surgical castrates (SC), and entire males (EM). Therefore, 128 male piglets were assigned to five treatment-groups and a long term follow-up group. IC groups received two vaccinations (V1, V2) with Improvac® at 8 and 12, 12 and 16, or 12 and 18 weeks. Testosterone-concentrations decreased significantly two weeks after V2 in feces and dropped in serum from V2 to slaughter (S) except IC-8/12 without differing significantly. GnRH-binding results indicated the highest values for IC-12/18 animals. While IC-12/16 and IC-12/18 animals showed boar taint compounds below the threshold levels, two IC-8/12 animals had concentrations above the threshold level. Feed-efficiency was higher in EM than in SC with IC in between. In IC compared to EM, a decreasing amount of polyunsaturated-fatty-acids was obvious and GnRH-vaccination reduced penile injuries. The examined vaccination protocols reduce penile injuries, improve feed efficiency and carcass quality, and reliably prevents boar taint, if manufacturer's recommendations concerning vaccination schedules are applied. Therefore immunocastration offers a reliable, animal friendly alternative to surgical castration.

7.
Fertil Steril ; 113(2): 417-425.e1, 2020 02.
Article in English | MEDLINE | ID: mdl-31973903

ABSTRACT

OBJECTIVE: To compare live birth and multiple gestation in patients diagnosed with unexplained infertility undergoing intrauterine insemination after ovarian stimulation (OS-IUI) with oral medications versus gonadotropins. DESIGN: Systemic review and meta-analysis. SETTING: Not applicable. PATIENT(S): Patients undergoing OS-IUI for treatment of unexplained infertility. INTERVENTION(S): Clomiphene, letrozole, or gonadotropins for OS-IUI. MAIN OUTCOME MEASURE(S): Live birth and multiple gestation. RESULT(S): Eight total trials were identified that met the inclusion criteria and comprised 2,989 patients undergoing 6,590 cycles. One study reported a significant increase in both live births and multiple gestations with the use of gonadotropins, two studies found an increased likelihood of live birth with the use of gonadotropins, and two studies found an increased risk of twins with gonadotropins. The relative risk of live birth in subjects receiving gonadotropins was 1.09. The relative risk of multiple gestation in subjects receiving gonadotropins was 1.06. Clinical pregnancy was higher in protocols with lax cancellation policies or higher gonadotropin doses, with subsequent increased relative risks of multiple gestations of 1.20 and 1.15, respectively. Singleton births per subject were similar between the two groups. The results did not change in per-protocol, per cycle, or fixed-effect model sensitivity analyses. CONCLUSION(S): For every birth gained with the use of gonadotropins, a similar increased risk of multiple gestation occurs. The randomized data do not support the use of gonadotropin for OS-IUI in women with unexplained infertility. CLINICAL TRIAL REGISTRATION NUMBER: Prospero CRD4201911998.


Subject(s)
Clomiphene/administration & dosage , Fertility Agents, Female/administration & dosage , Gonadotropins/administration & dosage , Infertility/therapy , Letrozole/administration & dosage , Ovary/drug effects , Ovulation Induction , Ovulation/drug effects , Administration, Oral , Adolescent , Adult , Clomiphene/adverse effects , Female , Fertility/drug effects , Fertility Agents, Female/adverse effects , Gonadotropins/adverse effects , Humans , Infertility/diagnosis , Infertility/etiology , Infertility/physiopathology , Insemination, Artificial , Letrozole/adverse effects , Live Birth , Male , Ovary/physiopathology , Ovulation Induction/adverse effects , Pregnancy , Pregnancy Rate , Randomized Controlled Trials as Topic , Risk Factors , Treatment Outcome , Young Adult
8.
J Am Chem Soc ; 141(39): 15586-15596, 2019 Oct 02.
Article in English | MEDLINE | ID: mdl-31438682

ABSTRACT

Recently developed chain walking (CW) catalysis is an elegant approach to produce materials with controllable structure and properties. However, there is still a lack in understanding of how the reaction mechanism influences the macromolecular structures. In this study, a series of dendritic polyethylenes (PE) synthesized by Pd-α-diimine-complex through CW catalysis (CWPE) is investigated by means of theory and experiment. Thereby, the exceptional ability of in situ tailoring polymer structure by varying synthesis parameters was exploited to tune the branching architecture, which allowed us to establish a precise relationship between synthesis, structure, and solution properties. The systematically produced polymers were characterized by state-of-the-art multidetector separation and neutron scattering experiments as well as atomic force microscopy to access molecular properties of CWPE. On a global scale, the CWPE appear in a worm-like conformation independently on the synthesis conditions. However, severe differences in their contraction factors suggested that CWPE differ substantially in topology. These observations were verified by NMR studies that showed that CWPE possess a constant total number of branches but varying branching distribution. Small angle neutron scattering experiments gave access to structural characteristics from global to segmental scale and revealed the unique heterogeneity of CWPE, which is predominantly based on differences in their dendritic side chains. The experimental data were compared to theoretical CW structures modeled with different reaction-to-walking probabilities. Simple theoretical arguments predict a crossover from dendritic to linear topologies yielding a structural range from purely linear to dendritic chain growth. Yet, comparison of theoretical and empirical scattering curves gave the first evidence that a transition state to worm-like topologies is actually experimentally accessible. This crossover regime is characterized by linear global features and dendritic local substructures contrary to randomly hyperbranched systems. Instead, the obtained CWPE systems have characteristics of disordered dendritic bottle brushes and can be adjusted by the walking rate/reaction probability of the catalyst.

9.
J Phys Condens Matter ; 30(49): 495001, 2018 Dec 12.
Article in English | MEDLINE | ID: mdl-30426969

ABSTRACT

Cetyltrimethylammonium bromide (CTAB) is one of the most commonly used surfactants in nanoparticle synthesis and stabilization. Usually, CTAB is used in high concentrations besides co-surfactants leading to well defined products but the complex mesoscopic CTAB structures stay mostly unknown. N-alcohols for instance are widely used co-surfactants which modify the properties of native CTAB dispersions. In this paper we report about a detailed structure analysis of n-alcohol modified CTAB micelles. In particular, n-pentanol and n-hexanol exhibit a significantly different influence on the size, shape and composition of CTAB micelles. Using a combination of small-angle x-ray spectroscopy (SAXS) and neutron scattering spectroscopy (SANS), we applied a method for a complete structural characterization of such micelles. The incorporation of n-pentanol into CTAB micelles generally does not influence the morphology but enhances the number of micelles due to the volume of the added alcohol. N-hexanol, however, leads to an elongation of the micelles as a function of its concentration. It was found by extended contrast variation measurements that this difference is caused by a different distribution of the alcohols between the micellar core and shell. N-pentanol molecules are generally located at the core-shell interface of the CTAB micelles with not only the head group but also two additional methylene bridging groups located in the micellar shell. This leads to an increase of its effective head group volume. In comparison, in n-hexanol modified micelles the whole alkyl chain is located within the micellar core. The detailed structure for n-alcohol modified CTAB micelles is described herein for the first time. The knowledge of the structural details found is indispensable for an in-depth understanding of CTAB-n-alcohol-water interfaces in general which is relevant for the synthesis of many functional nanostructures like mesoporous silica and gold or silver nanoparticles.

10.
Appl Microbiol Biotechnol ; 102(19): 8429-8436, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30073397

ABSTRACT

In industrial-scale microalgal cultures, non-target microalgae compete with the desired species for nutrients and CO2, thus reducing the growth rate of the target species and the quality of the produced biomass. Microalgae identification is generally considered a complicated issue; although, in the last few years, new molecular methods have helped to rectify this problem. Among the different techniques available, DNA barcoding has proven very useful in providing rapid, accurate, and automatable species identification; in this work, it is used to assess the genomic identity of the microalga species Scenedesmus sp. 'almeriensis', a common strain in industrial-scale cultures. Barcode markers rbcL and ITS1-5.8S-ITS2 were sequenced and the obtained genomic information was used to design a quantitative PCR assay to precisely quantify the S. almeriensis concentration in microalgal cultures of industrial interest. TaqMan chemistry was used to quantify down to 1 µg/L dry weight of S. almeriensis cells, including in the presence of concentrated mixed cultures of other microalgae. A simple direct qPCR approach was also investigated to avoid classic DNA extraction and to reduce total assay time to approximately 2 h. The objective was to design strain-specific tools able to confirm and quantify the presence of different strains in whatever microalgae culture so as to achieve maximal productivity and quality of the produced biomass.


Subject(s)
Microalgae/growth & development , Biomass , DNA Barcoding, Taxonomic/methods , Industry/methods , Microalgae/genetics , Scenedesmus/genetics , Scenedesmus/growth & development
11.
J Colloid Interface Sci ; 531: 672-680, 2018 Dec 01.
Article in English | MEDLINE | ID: mdl-30075319

ABSTRACT

HYPOTHESIS: An effective way for fixating vesicle structures is the insertion of monomers and cross-linking agents into their bilayer, and their subsequent polymerization can lead to the formation of polymeric nanocapsules. Particularly attractive here are vesicle systems that form spontaneously well-defined small vesicles, as obtaining such small nanocapsules with sizes below 100 nm is still challenging. EXPERIMENTS: A spontaneously forming well-defined vesicle system composed of the surfactants TDMAO (tetradecyldimethylamine oxide), Pluronic L35, and LiPFOS (lithium perfluorooctylsulfonate) mixture was used as template for fixation by polymerization. Therefore, styrene monomer was incorporated into the vesicle bilayer and ultimately these structures were fixated by UV induced radical polymerization. Structural alteration of the vesicles upon loading with monomer and the cross-linker as well as the effect of subsequent polymerization in the membrane were investigated in detail by turbidity measurements, dynamic and static light scattering, (DLS, SLS), and small angle neutron scattering (SANS). FINDINGS: The analysis showed the changes on vesicle structures due to the monomer loading, and that these structures can become permanently fixed by the polymerization process. The potential of this approach to produce well-defined nanocapsules starting from a self-assembled system and following polymerization is critically evaluated.

12.
J Chem Phys ; 146(20): 203309, 2017 May 28.
Article in English | MEDLINE | ID: mdl-28571384

ABSTRACT

A recent model for unentangled polymer chains in confinement [M. Dolgushev and M. Krutyeva, Macromol. Theory Simul. 21, 565 (2012)] is scrutinized by small-angle neutron scattering (SANS) with respect to its static prediction, the single-chain structure factor. We find a remarkable agreement although the model simplifies the effect of the confinement to a harmonic potential. The effective confinement size from fits of SANS data with the model agrees well with the actual pore size. Starting from this result we discuss the possibility of an experiment on the dynamic structure factor predicted by the model. It turns out that such an experiment would need a large ratio polymer dimension/pore size which is difficult but not impossible to achieve.

13.
Angew Chem Int Ed Engl ; 55(26): 7398-402, 2016 06 20.
Article in English | MEDLINE | ID: mdl-27140654

ABSTRACT

Ordered heterostructures of layered materials where interlayers with different reactivities strictly alternate in stacks offer predetermined slippage planes that provide a precise route for the preparation of bilayer materials. We use this route for the synthesis of a novel type of reinforced layered silicate bilayer that is 15 % stiffer than the corresponding monolayer. Furthermore, we will demonstrate that triggering cleavage of bilayers by osmotic swelling gives access to a generic toolbox for an asymmetrical modification of the two vis-à-vis standing basal planes of monolayers. Only two simple steps applying arbitrary commercial polycations are needed to obtain such Janus-type monolayers. The generic synthesis route will be applicable to many other layered compounds capable of osmotic swelling, rendering this approach interesting for a variety of materials and applications.

14.
Sci Rep ; 6: 22736, 2016 Mar 17.
Article in English | MEDLINE | ID: mdl-26984478

ABSTRACT

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.

15.
Article in English | MEDLINE | ID: mdl-26651699

ABSTRACT

We investigate the nonequilibrium behavior of dense, plastic-crystalline suspensions of mildly anisotropic colloidal hard dumbbells under the action of an oscillatory shear field by employing Brownian dynamics computer simulations. In particular, we extend previous investigations, where we uncovered nonequilibrium phase transitions, to other aspect ratios and to a larger nonequilibrium parameter space, that is, a wider range of strains and shear frequencies. We compare and discuss selected results in the context of scattering and rheological experiments. Both simulations and experiments demonstrate that the previously found transitions from the plastic crystal phase with increasing shear strain also occur at other aspect ratios. We explore the transition behavior in the strain-frequency phase and summarize it in a nonequilibrium phase diagram. Additionally, the experimental rheology results hint at a slowing down of the colloidal dynamics with higher aspect ratio.

16.
J Appl Crystallogr ; 48(Pt 6): 1849-1859, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26664343

ABSTRACT

Following demand from the user community regarding the possibility of improving the experimental resolution, the dedicated high-intensity/extended Q-range SANS diffractometer KWS-2 of the Jülich Centre for Neutron Science at the Heinz Maier-Leibnitz Center in Garching was equipped with a double-disc chopper with a variable opening slit window and time-of-flight (TOF) data acquisition option. The chopper used in concert with a dedicated high-intensity velocity selector enables the tuning at will of the wavelength resolution Δλ/λ within a broad range, from 20% (standard) down to 2%, in a convenient and safe manner following pre-planned or spontaneous decisions during the experiment. The new working mode is described in detail, and its efficiency is demonstrated on several standard samples with known properties and on a completely new crystallizable copolymer system, which were investigated using both the conventional (static) and TOF modes.

17.
Angew Chem Int Ed Engl ; 54(43): 12578-83, 2015 Oct 19.
Article in English | MEDLINE | ID: mdl-26296431

ABSTRACT

Dendronization of a hyperbranched polyester with different generation dendrons leads to pseudo-dendritic structures. The hyperbranched core is modified by the divergent coupling of protected monomer units to the functional groups. Compared to dendrimers, the synthetic effort is significantly less, but the properties are very close to those of high-generation dendrimers. The number of functional groups, molar mass, and rheology behavior even in the early generation (G1-G4) pseudo-dendrimers strongly resembles the behavior of dendrimers in higher generations (G5-G8). Comparison of the segmental and internal structure with perfect dendrimers is performed using SANS, dynamic light scattering and viscosity analysis, microscopy and molecular dynamics simulation. The interpretation of the results reveals unique structural characteristics arising from lower segmental density of the core, which turns into a soft nano-sphere with a smooth surface even in the first generation.

18.
Nanoscale ; 7(33): 13924-34, 2015 Sep 07.
Article in English | MEDLINE | ID: mdl-26219628

ABSTRACT

We present a comprehensive experimental and theoretical study covering micro-, meso- and macroscopic length and time scales, which enables us to establish a generalized view in terms of structure-property relationship and equilibrium dynamics of soft colloids. We introduce a new, tunable block copolymer model system, which allows us to vary the aggregation number, and consequently its softness, by changing the solvophobic-to-solvophilic block ratio (m : n) over two orders of magnitude. Based on a simple and general coarse-grained model of the colloidal interaction potential, we verify the significance of interaction length σint governing both structural and dynamic properties. We put forward a quantitative comparison between theory and experiment without adjustable parameters, covering a broad range of experimental polymer volume fractions (0.001 ≤ϕ≤ 0.5) and regimes from ultra-soft star-like to hard sphere-like particles, that finally results in the dynamic phase diagram of soft colloids. In particular, we find throughout the concentration domain a strong correlation between mesoscopic diffusion and macroscopic viscosity, irrespective of softness, manifested in data collapse on master curves using the interaction length σint as the only relevant parameter. A clear reentrance in the glass transition at high aggregation numbers is found, recovering the predicted hard-sphere (HS) value in the hard-sphere like limit. Finally, the excellent agreement between our new experimental systems with different but already established model systems shows the relevance of block copolymer micelles as a versatile realization of soft colloids and the general validity of a coarse-grained approach for the description of the structure and dynamics of soft colloids.

19.
Phys Chem Chem Phys ; 17(27): 17939-56, 2015 Jul 21.
Article in English | MEDLINE | ID: mdl-26095113

ABSTRACT

DNA-complexes with platelet-like, cationically modified lipid nanoparticles (cLNPs) are studied with regard to the formation of nanocomposite structures with a sandwich-like arrangement of the DNA and platelets. For this purpose suspensions of platelet-like triglyceride nanocrystals, stabilized by a mixture of two nonionic (lecithin plus polysorbate 80 or poloxamer 188) and one cationic stabilizer dimethyldioctadecylammonium (DODAB), are used. The structure of the platelets in the native suspensions and their DNA-complexes, ranging from the sub-nano to the micron scale, is investigated with small- and wide-angle scattering (SAXS, SANS, WAXS), calorimetry, photon correlation spectroscopy, transmission electron microscopy and computer simulations. The appearance of strong, lamellarly ordered peaks in the SAXS patterns of the DNA-complexes suggests a stacked arrangement of the nanocrystals, with the DNA being partially condensed between the platelets. This finding is supported with computer simulated small-angle scattering patterns of nanocrystal stacks, which can reproduce the measured small-angle scattering patterns on an absolute scale. The influence of the choice of the nonionic stabilizers and the amount of the cationic stabilizer DODAB on the structure of the native suspensions and the inner structure of their DNA-complexes is studied, too. Using high amounts of DODAB, lecithins with saturated acyl chains and polysorbate 80 instead of poloxamer 188 produces thinner nanocrystals, and thus decreases their repeat distances in the nanocomposites. Such nanocomposites could be of interest as DNA carriers, where the triglyceride platelets protect the sandwiched DNA from degradation.


Subject(s)
DNA/chemistry , Nanocomposites/chemistry , Triglycerides/chemistry , Lecithins/chemistry , Nanocomposites/ultrastructure , Neutron Diffraction , Poloxamer/chemistry , Polysorbates/chemistry , Quaternary Ammonium Compounds , Scattering, Small Angle , X-Ray Diffraction
20.
Langmuir ; 31(22): 5992-6000, 2015 Jun 09.
Article in English | MEDLINE | ID: mdl-25635343

ABSTRACT

We study the structure and viscoelastic behavior of 3D plastic crystals of colloidal dumbbells in an oscillatory shear field based on a combination of small-angle neutron scattering experiments under shear (rheo-SANS) and Brownian dynamics computer simulations. Sterically stabilized dumbbell-shaped microgels are used as hard dumbbell model systems which consist of dumbbell-shaped polystyrene (PS) cores and thermosensitive poly(N-isopropylacrylamide) (PNIPAM) shells. Under increasing shear strain, a discontinuous transition is found from a twinned-fcc-like crystal to a partially oriented sliding-layer phase with a shear-molten state in between. In the novel partially oriented sliding-layer phase, the hard dumbbells exhibit a small but finite orientational order in the shear direction. We find that this weak correlation is sufficient to perturb the nature of the nonequilibrium phase transition as known for hard sphere systems. The discontinuous transition for hard dumbbells is observed to be accompanied by a novel yielding process with two yielding events in its viscoelastic shear response, while only a single yielding event is observed for sheared hard spheres. Our findings will be useful in interpreting the shear response of anisotropic colloidal systems and in generating novel colloidal crystals from anisotropic systems with applications in colloidal photonics.

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