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This study analyzed the possibility of using plant-originated waste materials (black and green tea dust) as functional polyethylene fillers. The dependence between the size of the filler particles and their antioxidant potential is discussed. Six fractions were selected: below 50 µm, 50-100 µm, 100-200 µm, 200-400 µm, 400-630 µm and 630-800 µm. Significant differences between the effect of particle size and the antioxidant properties of black and green tea were found using the extraction method to analyze antioxidant activity (DPPH method) and total phenolic content (Folin-Ciocalteu method), suggesting a higher potential for using green tea as a filler with antioxidant properties, as well as the benefits of finer active filler distribution. Biomass waste fillers were mixed with low-density polyethylene LDPE SEB 853 I'm Green ® , Braskem. Those samples were oxidized at 100 °C for 5 and 15 days to investigate the radical scavenging properties of fillers in composites. Fourier transform infrared spectroscopic studies show that the addition of both types of filler prevents the thermo-oxidation of polyethylene for 5 days. After 15 days, all samples except the BTW 400-630 and 630-800 µm exhibited oxidation. The mechanical properties of the LDPE and its' composites were tested, and we noted an increased brittleness of neat LDPE after thermal oxidation. The addition of black tea particles above 100 µm in size prevents this behavior.

The widespread use of poly(lactic acid) (PLA) from packaging to engineering applications seems to follow the current global trend. The development of high-performance PLA-based blends has led to the commercial introduction of various PLA-based resins with excellent thermomechanical properties. The reason for this is the progress in the field of major PLA limitations such as low thermal resistance and poor impact strength. The main purpose of using biobased polymers in polymer blends is to increase the share of renewable raw materials in the final product rather than its possible biodegradation. However, in the case of engineering applications, the focus is on achieving the required properties rather than maximizing the percentage of biopolymer. The presented review article discusses the current strategies to optimize the balance of the key features such as stiffness, toughness, and heat resistance of PLA-based blends. Improving of these properties requires molecular structural changes, which together with morphology, crystallinity, and the influence of the processing conditions are the main subjects of this article. The latest research in this field clearly indicates the high potential of using PLA-based materials in highly demanding applications. In the case of impact strength modification, it is possible to obtain values close to 800 J/m, which is a value comparable to polycarbonate. Significant improvement can also be confirmed for thermal resistance results, where heat deflection temperatures for selected types of PLA blends can reach even 130 °C after modification. The modification strategies discussed in this article confirm that a properly conducted process of selecting the blend components and the conditions of the processing technique allows for revealing the potential of PLA as an engineering plastic.

Interesting alternatives to expensive biodegradable polymers are their composites with natural fillers. The addition of biochar to a blend of poly(lactic acid) (PLA) and poly(3-hydroxybutyrate- co -4-hydroxybutyrate) was studied, and the resulting materials were evaluated for their properties and changes during degradation. Introducing biochar as a filler brought a noticeable improvement in electrostatic properties. Surface resistivity decreased from 3.80 × 10 12 for the sample without biochar to 1.32 × 10 12 for the sample with 30% filler content. Degradation tests revealed distinct differences in the degradation profile for composites due to the presence of filler. Composites with a lower biochar content displayed curling crack edges during hydrolytic degradation, and when the filler content reached 20 wt%, PLA loss accelerated. This study suggests that biochar-based composites have potential to be used as sustainable materials with improved properties.

Transgender and gender diverse (TGD) young adults experience elevated risk for eating disorders (ED), partially due to cissexist discrimination and victimization; less is understood about how socioeconomic determinants contribute to their ED risk. Qualitative data collected from 66 TGD young adults (18-30 years old; 29% self-identified as transgender women, 29% as transgender men, 39% as nonbinary people, and 3% as another gender identity (e.g., māhū)) in eight asynchronous online focus groups explored how socioeconomic determinants in conjunction with other dimensions of identity and lived experience shape disordered eating behavior (DEB) and ED risk. Participants described how economic barriers-including poverty and dependency on others (e.g. parents for health insurance)-and challenges produced by insurance and healthcare systems impeded healthcare access to the detriment of their overall mental health and risk for ED. In addition, participants shared different ways they leveraged financial resources to cope with stress, sometimes in ways that impelled disordered eating behaviors. Finally, participants described how poverty, socioeconomic advantage and disadvantage, and classism compound other systems of oppression (e.g. racism, ableism, weight bias) to adversely impact their general health and ED risk.

Asymptotic giant branch stars are responsible for the production of most of the heavy isotopes beyond Sr observed in the solar system. Among them, isotopes shielded from the r-process contribution by their stable isobars are defined as s-only nuclei. For a long time the abundance of ^{204}Pb, the heaviest s-only isotope, has been a topic of debate because state-of-the-art stellar models appeared to systematically underestimate its solar abundance. Besides the impact of uncertainties from stellar models and galactic chemical evolution simulations, this discrepancy was further obscured by rather divergent theoretical estimates for the neutron capture cross section of its radioactive precursor in the neutron-capture flow, ^{204}Tl (t_{1/2}=3.78  yr), and by the lack of experimental data on this reaction. We present the first ever neutron capture measurement on ^{204}Tl, conducted at the CERN neutron time-of-flight facility n_TOF, employing a sample of only 9 mg of ^{204}Tl produced at the Institute Laue Langevin high flux reactor. By complementing our new results with semiempirical calculations we obtained, at the s-process temperatures of kT≈8  keV and kT≈30  keV, Maxwellian-averaged cross sections (MACS) of 580(168) mb and 260(90) mb, respectively. These figures are about 3% lower and 20% higher than the corresponding values widely used in astrophysical calculations, which were based only on theoretical calculations. By using the new ^{204}Tl MACS, the uncertainty arising from the ^{204}Tl(n,γ) cross section on the s-process abundance of ^{204}Pb has been reduced from ∼30% down to +8%/-6%, and the s-process calculations are in agreement with the latest solar system abundance of ^{204}Pb reported by K. Lodders in 2021.

The growing requirements regarding the safety of using polymers and their composites are related to the emergence of more effective, sustainable, and hazardous-limited fire retardants (FRs). Significant amounts of FRs are usually required to effectively affect a polymer's burning behavior, while the knowledge of their recycling potential is still insufficient. At the same time, concerns are related not only to the reduced effectiveness of flame retardancy but also, above all, to the potential deterioration of mechanical properties caused by the degradation of temperature-affected additives under processing conditions. This study describes the impact of the four-time reprocessing of bio-based polyamide 11 (PA11) modified with an intumescent flame-retardant (IFR) system composed of ammonium polyphosphate (APP), melamine cyanurate (MC), and pentaerythritol (PER) and its composites containing additional short basalt fibers (BFs). Composites manufactured via twin-screw extrusion were subjected to four reprocessing cycles using injection molding. A comprehensive analysis of their structural, mechanical, and fire behavior changes in each cycle was conducted. The obtained results confirmed the safety of using the proposed fire-retarded polyamide and its composites while reprocessing under the recommended process parameters without the risk of significant changes in the structure. The partial increase in flammability of reprocessed PA-based materials caused mainly by polymer degradation has been described.

This study details the design, fabrication, clinical trials' evaluation, and analysis after the clinical application of 3D-printed bone reconstruction implants made of nHAp@PLDLLA [nanohydroxyapatite@poly(L-lactide- co -D,L-lactide)] biomaterial. The 3D-printed formulations have been tested as bone reconstruction Cranioimplants in 3 different medical cases, including frontal lobe, mandibular bone, and cleft palate reconstructions. Replacing one of the implants after 6 months provided a unique opportunity to evaluate the post-surgical implant obtained from a human patient. This allowed us to quantify physicochemical changes and develop a spatial map of osseointegration and material degradation kinetics as a function of specific locations. To the best of our knowledge, hydrolytic degradation and variability in the physicochemical and mechanical properties of the biomimetic, 3D-printed implants have not been quantified in the literature after permanent placement in the human body. Such analysis has revealed the constantly changing properties of the implant, which should be considered to optimize the design of patient-specific bone substitutes. Moreover, it has been proven that the obtained composition can produce biomimetic, bioresorbable and bone-forming alloplastic substitutes tailored to each patient, allowing for shorter surgery times and faster patient recovery than currently available methods.

The use of biodegradable polymers as matrices in composites gives a wide range of applications, especially in niche areas. The assessment of the effect of the filler content on the change of mechanical properties makes it possible to optimize the composition for specific needs. Biochar was used as a filler in the studied composites with two different biodegradable blends as a matrix. Poly(1,4-butylene adipate- co -1,4-butylene terephthalate)/polylactide/biochar (PBAT/PLA/BC) and polylactide/poly[( R )-3-hydroxybutyrate- co -4-hydroxybutyrate]/biochar (PLA/P(3HB- co -4HB)/BC) composites with 0, 10, 15, 20 and 30 wt% of biochar underwent mechanical tests. The test results revealed a change in the properties of the composites related to the filler content. The results of the tensile test showed that increasing the biochar content increased the tensile modulus values by up to 100% for composites with 30 wt% of biochar, compared to unfilled matrices, and decreased the elongation associated with the breaking of PBAT/PLA and PLA/P(3HB- co -4HB) matrix composites. The elongation values at break of PBAT/PLA and PLA/(3HB- co -4HB) composites with 30 wt% biochar were reduced by 50% and 65%, respectively, compared to the unfilled matrices. PLA/P(3HB- co -4HB) matrix composites, in contrast to PBAT/PLA/BC, showed a decrease in tensile strength with the increases in filler content from 35.6 MPa for unfilled matrix to 27.1 MPa for PLA/P(3HB- co -4HB)/BC30 composites. An increase in filler content increased the brittleness of the composites regardless of the matrix used, as determined under the Charpy impact-test. This phenomenon was observed for all tested PLA/P(3HB- co -4HB) composites, for which the impact strength decreased from 4.47 kJ/m 2 for the matrix to 1.61 kJ/m 2 for the composite containing 30 wt% biochar. PBAT/PLA-based composites with 10 wt% of biochar showed slightly lower impact strength compared to the unfilled matrix, but composites with 30 wt% biochar showed 30% lower impact strength than PBAT/PLA. The complex viscosity value increased with increased filler content. For all composites tested on both polyester matrices, the viscosity decreased with increasing angular frequency.

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

The polymer foil industry is one of the leading producers of plastic waste. The development of new recycling methods for packaging products is one of the biggest demands in today's engineering. The subject of this research was the melt processing of multilayered PET-based foil waste with PETG copolymer. The resulting blends were intended for additive manufacturing processing using the fused deposition modeling (FDM) method. In order to improve the properties of the developed materials, the blends compounding procedure was conducted with the addition of a reactive chain extender (CE) and elastomeric copolymer used as an impact modifier (IM). The samples were manufactured using the 3D printing technique and, for comparison, using the traditional injection molding method. The obtained samples were subjected to a detailed characterization procedure, including mechanical performance evaluation, thermal analysis, and rheological measurements. This research confirms that PET-based film waste can be successfully used for the production of filament, and for most samples, the FDM printing process can be conducted without any difficulties. Unfortunately, the unmodified blends are characterized by brittleness, which makes it necessary to use an elastomer additive (IM). The presence of a semicrystalline PET phase improves the thermal resistance of the prepared blends; however, an annealing procedure is required for this purpose.

Transgender women (TW) face inequities in HIV and unique barriers to PrEP, an effective biomedical intervention to prevent HIV acquisition. To improve PrEP retention among TW, we examined factors related to retention using a two-phase, sequential explanatory mixed methods approach. In Phase I, we used data from a trial of 170 TW who were provided oral PrEP to examine predictors of 24-week retention. In Phase II, we conducted 15 in-depth interviews with PrEP-experienced TW and used thematic analysis to explain Phase I findings. In Phase I, more participants who were not retained at 24 weeks reported sex work engagement (18% versus 7%) and substantial/severe drug use (18% versus 8%). In Phase II, participants reported drug use as a barrier to PrEP, often in the context of sex work, and we identified two subcategories of sex work. TW engaged in "non-survival sex work" had little difficulty staying on PrEP, while those engaged in "survival sex work" struggled to stay on PrEP. In Phase I, fewer participants not retained at 24 weeks reported gender-affirming hormone therapy (GAHT) use (56% versus 71%). In Phase II, participants prioritized medical gender affirmation services over PrEP but also described the bidirectional benefits of accessing GAHT and PrEP. TW who engaged in "survival sex work" experience barriers to PrEP retention (e.g., unstable housing, drug use) and may require additional support to stay in PrEP care.

The surface modification of poly(lactic acid) (PLA) using hydroxyapatite (HAP) particles via Langmuir-Blodgett (LB) and Langmuir-Schaefer (LS) approaches has been reported. The HAP monolayer was characterized at the air/water interface and deposited on three-dimensional (3D) printed poly(lactic acid). The deposition of HAP particles using the LS approach led to a larger surface coverage in comparison to the LB method, which produces a less uniform coating because of the aggregation of the particles. After the transfer of HAP on the PLA surface, the wettability values remained within the desired range. The presence of HAP on the surface of the polymer altered the topography and roughness in the nanoscale, as evidenced by the atomic force microscopy (AFM) images. This effect can be beneficial for the osteointegration of polymeric implants at an early stage, as well as for the reduction of the adherence of the microbial biofilm. Overall, the results suggest that the LS technique could be a promising approach for surface modification of PLA by hydroxyapatite with respective advantages in the biomedical field.

Biodegradable craniofacial and cranial implants are a new aspect in terms of reducing potential complications, especially in the long term after surgery. They are also an important contribution in the field of surgical reconstructions for children, for whom it is important to restore natural bone in a relatively short time, due to the continuous growth of bones. The aim of this study was to verify the impact of the technology on biodegradability and to estimate the risk of inappropriate implant resorption time, which is an important aspect necessary to select prototypes of implants for in vivo testing. Prototypes of implants were made using two technologies: 3D printing using a PLDLA: poly(L-co-D,L lactide) (PLDLA) filament containing hydroxyapatite nanoparticles, and injection using PLDLA. After the radiation sterilization process, they were subjected to in vitro degradation under accelerated conditions. As part of this study, the in vitro degradation of newly developed biodegradable implant technologies was assessed in accordance with the guidelines of European standards. It was found that the implant manufacturing process had a significant impact on the degradation time under simulated conditions in various media. Implants made using the injection technique were characterized by lower susceptibility to degradation media compared to the 3D-printed implant under accelerated conditions.

Transgender and gender diverse (TGD) youth experience significant risk for negative health outcomes, yet few studies exist that address TGD youth's experiences of health care. This paper explores the equitable access and utilization of health care in a sample of TGD youth of diverse gender and racial/ethnic identities. Data for this analysis are from the TGD subsample (n = 1415) of the 2018 Survey of Today's Adolescent Relationships and Transitions (START) Project. We assessed five health care experiences: being insured, having a current health care provider, being out to one's provider, believing your provider was knowledgeable about transgender issues, and barriers to accessing care due to gender identity/expression. We examined the proportion of TGD youth who reported each of these outcomes and within-group differences by gender identity and race/ethnicity using descriptive statistics, logistic regression, and predicted probabilities. When differences were examined by gender identity, barriers to equitable care were consistently more present among transgender females than youth of other gender identities. There were few significant differences by race/ethnicity; however, dual referent models demonstrated barriers to equitable care were particularly evident among Black and Hispanic transgender women. We discuss these findings through the lens of intersectionality and highlight the importance of research and intervention work focused on reducing barriers to equitable care for TGD youth., (© 2023. Society for Prevention Research.)

Nucleosides are essential cornerstones of life, and nucleoside derivatives and synthetic analogues have important biomedical applications. Correspondingly, production of non-canonical nucleoside derivatives in animal model systems is of particular interest. Here, we report the discovery of diverse glucose-based nucleosides in Caenorhabditis elegans and related nematodes. Using a mass spectrometric screen based on all-ion fragmentation in combination with total synthesis, we show that C. elegans selectively glucosylates a series of modified purines but not the canonical purine and pyrimidine bases. Analogous to ribonucleosides, the resulting gluconucleosides exist as phosphorylated and non-phosphorylated forms. The phosphorylated gluconucleosides can be additionally decorated with diverse acyl moieties from amino acid catabolism. Syntheses of representative variants, facilitated by a novel 2'- O- to 3'- O -dibenzyl phosphoryl transesterification reaction, demonstrated selective incorporation of different nucleobases and acyl moieties. Using stable-isotope labeling, we further show that gluconucleosides incorporate modified nucleobases derived from RNA and possibly DNA breakdown, revealing extensive recycling of oligonucleotide catabolites. Gluconucleosides are conserved in other nematodes, and biosynthesis of specific subsets is increased in germline mutants and during aging. Bioassays indicate that gluconucleosides may function in stress response pathways.

Germanium monosulfide with an anisotropic puckered crystalline structure has recently attracted much attention due to its unique optical and electronic properties; however, exciton-phonon interactions were only superficially elucidated. We study the resonant Raman scattering and the photoluminescence of the optically active Γ-exciton in layered GeS flakes and evaluate the exciton and phonon responses on variations in the excitation energy, laser-light and emission polarizations, temperature, and laser power. A double-resonance mechanism allows for observing Raman forbidden (dark) first- and second-order longitudinal-optical phonon modes whose symmetries and energies are moreover calculated by density functional perturbation theory. For (quasi)-resonant exciton excitation, the selection rules become relaxed so that a fourth-order Fröhlich intraband process is mediated by the scattering of the electron with a longitudinal-optical and an acoustic phonon. Our results demonstrate considerable coupling between phonons and photogenerated carriers in GeS flakes and the high efficiency of multiorder scattering in optical processes.

Purpose: Our purpose was to assess the association between Gender-Sexuality Alliances (GSAs) advisors' self-efficacy to address transgender issues and their students' depressive symptoms, by students' gender identity (i.e., transgender vs. cisgender). We predict that higher advisor self-efficacy will be associated with decreases in student depressive symptoms for transgender students, though not necessarily for cisgender students. Methods: Data come from surveys of student members ( n  = 366) and advisors ( n  = 58) of 38 purposively sampled GSAs in Massachusetts high schools, in 2016-2017 and 2017-2018. We used a linear mixed-effects model to assess the association between advisor self-efficacy to address transgender issues and student change in Center for Epidemiological Studies Depression-10 scores between the beginning and end of the school year by gender identity, adjusting for student covariates. Results: Students were 10-20 years old (mean = 15, standard deviation [SD] = 1.4); 28% were transgender, 28% were students of color, and 86% were lesbian, gay, bisexual, or queer/questioning or other non-heterosexual identity. The GSA advisor self-efficacy scores ranged from 13 to 25 with a mean of 20.4 (SD = 3.0). Greater advisor self-efficacy to address transgender issues was associated with a decrease in depressive symptoms for transgender students (estimate = -0.47, p  = 0.01), but not for cisgender students. Conclusions: GSA advisor self-efficacy to address transgender issues could be protective for transgender student depressive symptoms. Thus, increasing advisor self-efficacy to address transgender issues may help decrease depressive symptomatology for transgender youth, and intervention work in this area is needed to bolster this claim.

The review article presents the technology of producing polyolefin-based films by extrusion casting. Due to the wide use of this type of film as packaging for food and other goods, obtaining films with favorable properties is still a challenge for many groups of producers in the plastics market. The feedblock process and multimanifold process are the main methods of producing multi-layer film. In the case of food films, appropriate barrier properties are required, as well as durability and puncture resistance also at low temperatures. On the other hand, in order to properly pack and present products, an appropriate degree of transparency must be maintained. Therefore, processing aids such as anti-slip, anti-block and release agents are commonly used. Other popular modifiers, such as waxes, fatty acid amides and mineral fillers-silica, talc or calcium carbonate-and their use in film extrusion are discussed. The article also presents common production problems and their prevention.

Our objective was to estimate disparities in binge drinking among secondary school students in California at the intersection of gender identity, race, and ethnicity, without aggregating racial and ethnic categories. We combined two years of the Statewide middle and high school California Healthy Kids Survey (n=951,995) and regressed past month binge drinking on gender identity (i.e., cisgender, transgender, or not sure of their gender identity), race (i.e., white, American Indian or Alaskan Native, Asian, Black or African American, Native Hawaiian or Pacific Islander, or multiracial), and ethnicity (i.e., Hispanic/Latinx or non-Hispanic/Latinx), and their interaction. Transgender students had greater odds of reporting past month binge drinking than cisgender students, with greater magnitudes among students with minoritized racial or ethnic identities compared to non-Hispanic/Latinx white students. For example, among non-Hispanic/Latinx white students, transgender students had 1.3 times greater odds (AOR=1.30, 95% CI=1.17-1.55), whereas among Hispanic/Latinx Black or African American students, transgender students had 5.3 times greater odds (AOR=5.33, 95% CI=3.84-7.39) of reporting past month binge drinking than cisgender students. Transgender adolescents, particularly those with minoritized racial or ethnic identities, may be at disproportionate risk of binge drinking. Interventions that address systemic racism and cisgenderism from an intersectional perspective are needed., Competing Interests: Conflicts of interest: “The authors have no conflicts of interest relevant to this article to disclose.”

A new type of partially biobased reinforcing filler system was developed in order to be used as a flame retardant for polylactic acid (PLA) and polypropylene (PP)-based composites. The prepared materials intended for injection technique processing were melt blended using the novel system containing ammonium polyphosphate (EX), biocarbon (BC), and basalt fibers (BF). All of the prepared samples were subjected to a detailed analysis. The main criterion was the flammability of composites. For PLA-based composites, the flammability was significantly reduced, up to V-0 class. The properties of PLA/EX/BC and PLA/EX/(BC-BF) composites were characterized by their improved mechanical properties. The conducted analysis indicates that the key factor supporting the effectiveness of EX flame retardants is the addition of BC, while the use of BF alone increases the flammability of the samples to the reference level. The results indicate that the developed materials can be easily applied in industrial practice as effective and sustainable flame retardants.

The presented research was focused on the development of a new method of sandwich structure manufacturing involving FDM-printing (fused deposition modeling) techniques and compression molding. The presented concept allows for the preparation of thermoplastic-based composites with enhanced mechanical properties. The sample preparation process consists of 3D printing the sandwich's core structure using the FDM method. For comparison purposes, we used two types of GPET (copolymer of polyethylene terephthalate)-based filaments, pure resin, and carbon fiber (CF)-reinforced filaments. The outer reinforcing layer "skins" of the sandwich structure were prepared from the compression molded prepregs made from the LCP (liquid-crystal polymer)-fiber fabric with the GPET-based matrix. The final product consisting of an FDM-printed core and LCP-based prepreg was prepared using the compression molding method. The prepared samples were subjected to detailed materials analyses, including thermal analyses (thermogravimetry-TGA, differencial scanning calorimetry-DSC, and dynamic thermal-mechanical analysis-DMTA) and mechanical tests (tensile, flexural, and impact). As indicated by the static test results, the modulus and strength of the prepared composites were slightly improved; however, the stiffness of the prepared materials was more related to the presence of the CF-reinforced filament than the presence of the composite prepreg. The main advantage of using the developed method is revealed during impact tests. Due to the presence of long LCP fibers, the prepared sandwich samples are characterized by very high impact resistance. The impact strength increased from 1.7 kJ/m 2 for pure GPET samples to 50.4 kJ/m 2 for sandwich composites. For GPET/CF samples, the increase is even greater. The advantages of the developed solution were illustrated during puncture tests in which none of the sandwich samples were pierced.

The subject of the presented research focuses on a comparative assessment of three types of polymer fillers used to modify highly crystalline poly(lactic acid) PLA intended for the FDM technique. The aim of the presented work was to determine the performance of the developed materials. The key aspect of the work was the use of polymer fillers of three different types. Nano-sized montmorillonite (MMT), biobased biocarbon (BC) and mineral talc. The several types of composites were prepared using extrusion technique. The maximum content for BC and talc filler was limited to 20 wt%, while for MMT it was 5 wt%. Prepared samples were subjected to detailed material analysis including mechanical tests (tensile, flexural, Charpy), thermal analysis (DSC, DMTA), HDT/Vicat tests and structure analysis. The results of the test confirmed that even relatively small amount of nano-type filler can be more efficient than micrometric particles. The used type of matrix was highly crystalline PLA, which resulted in a significant nucleation effect of the crystalline structure. However, thermomechanical tests revealed no improvement in thermal resistance. Microscopic survey confirmed that for MMT and talc filler the structure anisotropy was leading to more favorable properties, especially when compared to structures based on spherical BC particles.

The development of new polymer compositions characterized by a reduced environmental impact while lowering the price for applications in large-scale production requires the search for solutions based on the reduction in the polymer content in composites' structure, as well as the use of fillers from sustainable sources. The study aimed to comprehensively evaluate introducing low-cost inorganic fillers, such as copper slag (CS), basalt powder (BP), and expanded vermiculite (VM), into the flame-retarded ammonium polyphosphate polyethylene composition (PE/APP). The addition of fillers (5-20 wt%) increased the stiffness and hardness of PE/APP, both at room and at elevated temperatures, which may increase the applicability range of the flame retardant polyethylene. The deterioration of composites' tensile strength and impact strength induced by the presence of inorganic fillers compared to the unmodified polymer is described in detail. The addition of BP, CS, and VM with the simultaneous participation of APP with a total share of 40 wt% caused only a 3.1, 4.6, and 3 MPa decrease in the tensile strength compared to the reference value of 23 MPa found for PE. In turn, the cone calorimeter measurements allowed for the observation of a synergistic effect between APP and VM, reducing the peak heat rate release (pHRR) by 60% compared to unmodified PE. Incorporating fillers with a similar thermal stability but differing particle size distribution and shape led to additional information on their effectiveness in changing the properties of polyethylene. Critical examinations of changes in the mechanical and thermomechanical properties related to the structure analysis enabled the definition of the potential application perspectives analyzed in terms of burning behavior in a cone calorimetry test. Adding inorganic fillers derived from waste significantly reduces the flammability of composites with a matrix of thermoplastic polymers while increasing their sustainability and lowering their price without considerably reducing their mechanical properties, which allows for assigning developed materials as a replacement for flame-retarded polyethylene in large-scale non-loaded parts.

Purpose: Surveys suggest that the general public (i.e., adults or parents) supports sexual health education in schools. However, the number of schools providing sex education continues to decline in the United States. The purpose of this study is to conduct a meta-analysis of U.S.-based representative surveys to provide a pooled estimate of public support for sexual health education delivered in schools., Methods: A systematic search of three databases (Medline, PsycInfo, and ERIC) was conducted to identify survey measuring adult and parent attitudes toward sexual health education in school between 2000 and 2016. Meta-analyses were conducted in OpenMetaAnalyst via the metaphor package in R using a DerSimonian-Laird random effect models to account for heterogeneity between surveys., Results: A total of 23 citations met study inclusion and exclusion criteria, representing 15 unique probability surveys conducted with the public. Among the included surveys, 14 were nationwide and 11 included parents or an overrepresentation of parents. Across all survey findings, 88.7% (95% confidence interval = 86.2-91.2) of respondents supported sexual health education. Among surveys that only included parents or oversampled for parents, 90.0% (95% confidence interval = 86.5-93.4) supported sexual health education, and among nationally representative surveys, 87.7% (95% confidence interval = 85.1-90.6) of respondents supported sexual health education., Conclusion: These findings demonstrate overwhelming support for sexual health education delivered in schools. Additional research is needed to determine individual differences in support for specific sexual health education topics and skills delivered through classroom-based instruction., (Published by Elsevier Inc.)

Background: Transgender adolescents use vape products (eg, e-cigarettes) at higher rates than cisgender adolescents. Little is known about how these disparities differ from the intersectional perspective of both gender identity and race/ethnicity., Methods: We examined disparities in past 30-day vaping frequency at the intersection of gender identity and race/ethnicity among adolescents participating in two pooled waves of the population-based California Healthy Kids Survey (N = 953 445; 2017-2019). Generalized linear mixed models included gender identity-by-race/ethnicity interactions and adjusted for potential confounders. Stratified models quantified relationships between gender identity and vaping within race/ethnicity strata and between race/ethnicity and vaping within gender identity strata., Results: Transgender adolescents of color were more likely to report a higher frequency of vaping than cisgender white adolescents. In models stratified by race/ethnicity, transgender adolescents evidenced greater odds of more frequent vaping than cisgender adolescents of the same race/ethnicity; disparities were greatest between transgender and cisgender Black adolescents (adjusted odds ratio [AOR]: 6.05, 95% CI: 4.76-7.68) and smallest between transgender and cisgender white adolescents (AOR: 1.20, 95% CI: 1.06-1.35). In models stratified by gender identity, disparities were greatest between transgender Black and transgender white adolescents (AOR: 2.85, 95% CI: 2.20-3.70) and smallest between transgender multiracial and transgender white adolescents (AOR: 1.28, 95% CI: 1.05-1.58). Similar, though less consistent, patterns emerged for adolescents of color unsure of their gender identity relative to cisgender white adolescents., Conclusion: Transgender adolescents of color may be especially vulnerable to vaping disparities. Future research should identify and intervene on causal mechanisms undergirding disparities., Implications: Research finds that transgender adolescents use vape products at higher rates than their cisgender peers, however, little is known about how patterns of adolescent vaping may differ by both gender identity and race/ethnicity, information needed to inform culturally tailored prevention and control initiatives to decrease adolescent vaping disparities. Our analysis of data from a population-based adolescent health survey finds evidence of magnified disparities in vaping frequency among transgender adolescents of color., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment., (© The Author(s) 2022.)

In this study, we propose designs of an interband cascade laser (ICL) active region able to emit in the application-relevant mid infrared (MIR) spectral range and to be grown on an InP substrate. This is a long-sought solution as it promises a combination of ICL advantages with mature and cost-effective epitaxial technology of fabricating materials and devices with high structural and optical quality, when compared to standard approaches of growing ICLs on GaSb or InAs substrates. Therefore, we theoretically investigate a family of type II, "W"-shaped quantum wells made of InGaAs/InAs/GaAsSb with different barriers, for a range of compositions assuring the strain levels acceptable from the growth point of view. The calculated band structure within the 8-band k·p approximation showed that the inclusion of a thin InAs layer into such a type II system brings a useful additional tuning knob to tailor the electronic confined states, optical transitions' energy and their intensity. Eventually, it allows achieving the emission wavelengths from below 3 to at least 4.6 μm, while still keeping reasonably high gain when compared to the state-of-the-art ICLs. We demonstrate a good tunability of both the emission wavelength and the optical transitions' oscillator strength, which are competitive with other approaches in the MIR. This is an original solution which has not been demonstrated so far experimentally. Such InP-based interband cascade lasers are of crucial application importance, particularly for the optical gas sensing.

In this paper, the photoluminescence spectra of excitons in ZnO/ZnMgO/ZnO double asymmetric quantum wells grown on a-plane Al2O3 substrates with internal electric-field bands structures were studied. In these structures, the electron and the hole in the exciton are spatially separated between neighbouring quantum wells, by a ZnMgO barrier with different thickness. The existence of an internal electric field generates a linear potential and, as a result, lowers the energy of quantum states in the well. For the wide wells, the electrons are spatially separated from the holes and can create indirect exciton. To help the understanding of the photoluminescence spectra, for single particle states the 8 k·p for wurtzite structure is employed. Using these states, the exciton in the self-consistent model with 2D hydrogenic 1s-like wave function is calculated.

Background: Transgender youth report high rates of negative experiences in schools. Using a lens of minority stress, this study sought to examine in-school experiences of transgender youth to understand youth coping and to identify key opportunities for improving school environments for transgender youth., Methods: Participants included 41 youth across 33 in-depth interviews (M age  = 21.7) and two focus groups (N = 8; M age  = 17.3). Thematic analysis was used to analyze data. Themes related to stress, coping, and facilitators/barriers to stress/coping were derived and coded., Results: Distal stressors, such as structural discrimination and prejudice events, were found to contribute to the exclusion of transgender youth from school life, while proximal stressors, such as concealment and expectations of rejection, reinforced transgender youth's feelings of personal isolation. Participants expressed coping with both challenges by advocating for inclusion through direct action with teachers and administrators and seeking/finding connection with trusted staff and peers., Conclusions: Findings suggest that creating safe and supportive environments at school for transgender youth is an attainable goal, as all identified barriers to inclusivity and connection were modifiable. By considering the needs of transgender youth in policies and programming, schools may improve climate for and wellbeing of transgender students., (© 2021 American School Health Association. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Background: Multiple protective factors at the individual and environmental levels have been associated with prescription opioid misuse (POM) among adolescents. The literature may benefit by extending this research to consider the association between cumulative protective factors and current (ie, within the past 30 days) POM., Methods: The 2017 Virginia Youth Survey (part of the Youth Risk Behaviour Surveillance System) (N=3697) was used to investigate recent POM and the presence of individual and cumulative protective factors among high school students. Youth were asked to indicate whether they had engaged POM within the past 30 days. A set of protective factors representing youths' internal assets (eg, aspirational plans for education) and external resources (eg, family meals, safe school environment) were investigated as predictors of current POM, followed by testing of a cumulative protective factor score. Logistic regression models estimated ORs and 95% CIs., Results: When including demographics and risk factors in the model, none of the individual protective factors were significantly associated with current POM. Alternatively, the cumulative protective factor score was significantly associated with a decrease in the odds of current POM., Conclusions: The cumulative protective factor score was significantly associated with a decrease in the odds of current POM among high school students in Virginia. Programmes designed to provide multiple forms of support may be effective strategies for preventing current POM., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

This paper presents results of research on the preparation of biochar-modified rigid polyurethane foams that could be successfully used as thermal insulation materials. The biochar was introduced into polyurethane systems in an amount of up to 20 wt.%. As a result, foam cells became elongated in the direction of foam growth and their cross-sectional areas decreased. The filler-containing systems exhibited a reduction in their apparent densities of up to 20% compared to the unfilled system while maintaining a thermal conductivity of 25 mW/m·K. Biochar in rigid polyurethane foams improved their dimensional and thermal stability.

Needle visualization in the ultrasound image is essential to successfully perform the ultrasound-guided core needle biopsy. Automatic needle detection can significantly reduce the procedure time, false-negative rate, and highly improve the diagnosis. In this paper, we present a CNN-based, fully automatic method for detection of core needle in 2D ultrasound images. Adaptive moment estimation optimizer is proposed as CNN architecture. Radon transform is applied to locate the needle. The network's model was trained and tested on the total of 619 2D images from 91 cases of breast cancer. The model has achieved an average weighted intersection over union (the weighted Jaccard Index) of 0.986, F1 Score of 0.768, and angle RMSE of 3.73°. The obtained results exceed the other solutions by at least 0.27 and 7° in case of F1 score and angle RMSE, respectively. Finally, the needle is detected in a single frame averagely in 21.6 ms on a modern PC.

Purpose: We assessed the association of receipt of medical gender affirmation services (e.g., hormones, surgery) with HIV and other sexually transmitted disease (STD) prevention and knowledge indicators among transgender youth. Methods: A United States online sample of sexually experienced transgender youth ages 13-24 years ( N  = 1029) in 2018 completed a cross-sectional survey, including questions about sociodemographics, medical gender affirmation, and HIV and STD prevention outcomes (HIV testing, STD testing, pre-exposure prophylaxis [PrEP] awareness, and nonoccupational postexposure prophylaxis [nPEP] awareness). Logistic regression models were fit to assess the association of medical gender affirmation with HIV and STD prevention outcomes. Interaction terms and stratified models assessed differences in the association between medical gender affirmation and outcomes by gender identity. Results: Participants' mean age was 19.1 (standard deviation = 2.7), 45% were transgender female, 29% transgender male, 26% nonbinary, 53% were youth of color, and 19% accessed medical gender affirmation services. Medical gender affirmation was associated with increased odds of STD testing (adjusted odds ratio [aOR] = 1.90; 95% confidence interval [CI] = 1.33-2.73) with no significant interactions by gender identity. Associations between medical gender affirmation and awareness of PrEP and nPEP varied by gender identity. Among transgender male youth, medical gender affirmation was associated with awareness of PrEP (aOR = 2.65; 95% CI = 1.50-4.71) and nPEP (aOR = 2.03; 95% CI = 1.12-3.71). Among nonbinary youth, medical gender affirmation was associated with awareness of PrEP (aOR = 3.47; 95% CI = 1.26-11.27). Conclusion: Medical gender affirmation was associated with uptake and awareness of sexual health services. Bolstering medical gender affirmation for transgender youth may also bolster preventive health services broadly.

The presented study focuses on the development of flax fiber (FF) reinforced composites prepared with the use of poly(lactic acid)/poly(butylene adipate-co-terephthalate)-PLA/PBAT blend system. This type of modification was aimed to increase impact properties of PLA-based composites, which are usually characterized by high brittleness. The PLA/PBAT blends preparation was carried out using melt blending technique, while part of the samples was prepared by reactive extrusion process with the addition of chain extender (CE) in the form of epoxy-functionalized oligomer. The properties of unreinforced blends was evaluated using injection molded samples. The composite samples were prepared by compression molding technique, while flax fibers reinforcement was in the form of plain fabric. The properties of the laminated sheets were investigated during mechanical test measurements (tensile, flexural, impact). Differential scanning calorimetry (DSC) analysis was used to determine the thermal properties, while dynamic mechanical thermal analysis (DMTA) and heat deflection temperature (HDT) measurements were conducted in order to measure the thermomechanical properties. Research procedure was supplemented with structure evaluation using scanning electron microscopy (SEM) analysis. The comparative study reveals that the properties of PLA/PBAT-based composites were more favorable, especially in the context of impact resistance improvement. However, for CE modified samples also the modulus and strength was improved. Structural observations after the impact tests confirmed the presence of the plastic deformation of PLA/PBAT matrix, which confirmed the favorable properties of the developed materials. The use of PBAT phase as the impact modifier strongly reduced the PLA brittleness, while the reactive extrusion process improves the fiber-matrix interactions leading to higher stiffness and strength.

Transgender youth are more likely than cisgender youth to report health risks related to violence victimization, substance use, mental health, and sexual health. Parental support may help foster resilience and better health outcomes among this population. However, limited research has characterized parental support among transgender youth. To address this gap, we conducted a thematic analysis of 33 in-depth interviews with transgender youth. We coded interviews using the dimensions of the social support framework (i.e., emotional, instrumental, appraisal, and informational) as well as inductive codes to identify emergent themes. Almost all participants described some form of general parental support (e.g., expressions of love, housing, advice, and affirmation). Parental support specific to gender identity was also noted (e.g., emotional support for coming out as transgender and chosen name and pronoun use) but was more limited. Parents may benefit from resources and programming to promote acceptance and gender-affirming behaviors.

An automated vendor-independent system for dose monitoring in computed tomography (CT) medical examinations involving ionizing radiation is presented in this paper. The system provides precise size-specific dose estimates (SSDE) following the American Association of Physicists in Medicine regulations. Our dose management can operate on incomplete DICOM header metadata by retrieving necessary information from the dose report image by using optical character recognition. For the determination of the patient's effective diameter and water equivalent diameter, a convolutional neural network is employed for the semantic segmentation of the body area in axial CT slices. Validation experiments for the assessment of the SSDE determination and subsequent stages of our methodology involved a total of 335 CT series (60 352 images) from both public databases and our clinical data. We obtained the mean body area segmentation accuracy of 0.9955 and Jaccard index of 0.9752, yielding a slice-wise mean absolute error of effective diameter below 2 mm and water equivalent diameter at 1 mm, both below 1%. Three modes of the SSDE determination approach were investigated and compared to the results provided by the commercial system GE DoseWatch in three different body region categories: head, chest, and abdomen. Statistical analysis was employed to point out some significant remarks, especially in the head category., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reporeted in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: Transgender populations experience health inequities that underscore the importance of ensuring access to high quality care. We thematically summarize the health care experiences of transgender youth living in the southeast United States to identify potential barriers and facilitators to health care., Design and Methods: Transgender youth recruited from community settings in an urban area of the southeast United States participated in individual interviews (n = 33) and focus groups (n = 9) about protective factors. We conducted a thematic analysis of data from 42 participants who described their experiences seeking and receiving health care., Results: Participants reported a wide range of gender identities. The individual interview sample was majority Black (54.5%) and the mean age was 21.7 years and focus group participants were all white and the mean age was 16.8 years. Participants described numerous barriers to health care, including limited availability of gender affirming care, logistical challenges, such as gatekeeping and cost, concerns about confidentiality in relation to sexual behavior and gender identity, and inadequate cultural competency among providers regarding gender-affirming care. Facilitators included intake procedures collecting chosen pronouns and names and consistent use of them by providers, and open communication, including active listening., Conclusions: Findings underscore the need for a multi-component approach to ensure both transgender- and youth-friendly care., Practice Implications: Providers and office staff may benefit from transgender cultural competency trainings. In addition, clinic protocols relating to confidentiality and chosen name and pronoun use may help facilitate access to and receipt of quality care., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Legislative restrictions and the needs of consumers have created a demand for sustainable materials. Polylactide (PLA) is a biodegradable polyester with advantageous mechanical properties, however, due to its low crystallization rate, it also has low thermomechanical stability. Its range of application temperatures can be widened using nucleating agents and fillers including basalt powder (BP), a waste product from the mining industry. This study analyzed the possibility of enhancing the properties of a PLA-BP composite by chemically treating the filler. Basalt powder was subjected to silanization with 3-aminopropyltriethoxysilane or γ-glycidoxypropyltrimethoxysilane and mixed with PLA at 5-20 wt%. The nucleating effect of a potassium salt of 3,5-bis(methoxycarbonyl) (LAK-301) in the silanized composite was also evaluated. The properties of the materials with silanized BP were compared with the unmodified basalt powder. The miscibility of the filler and the polymer was assessed by oscillatory rheometry. The structure of the composites was studied using scanning electron microscopy and their thermomechanical properties were analyzed using dynamic mechanical thermal analysis. Mechanical properties such as tensile strength, hardness and impact strength, and heat deflection temperature of the materials were also determined. It was concluded that BP-filled nucleated PLA composites presented satisfactory thermomechanical stability without silanization, but chemical treatment could improve the matrix-filler interactions.

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92  yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

The leakage of any substances at the sea bottom consequently leads to contamination. The polluted area will strongly depend on the type of pollution which can be dissolved, material and the physical state of the bottom layers. Although the systems that monitor the particles or pollution on the sea surface already exists, there is no similar tool for the bottom area. This work aims at developing the High Resolution Dispersion Model (HRDM) that calculates transport of the pollution in case of potential leakage from chemical ammunition dumped into the Baltic Sea. The model has been embedded into existing operational system that covers the whole region of the Baltic Sea. Thus, it consists of the three main elements: operational atmospheric model that makes calculations every day, coupled ice-ocean model covering the whole Baltic Sea area and HRDM. The horizontal resolution of the atmospheric part is about 10 km, the coupled system is driven on 2.3 km grid and HRDM is implemented on 50 m horizontal resolution. The clients are able to make integration since 2014. Access to the system is granted via REpresentational State Transfer (REST) API that separates user interface from the server site. It is possible to make simulations for instantaneous and continuous type of leakage. The results are served in binary form (as a netcdf file) and as a georeferenced tiff picture. The temporal resolution of the output data is 1 h. The HRDM consists of half-life of sulfur mustard and the results for both - with and without half-life calculations are included in the output files. The HRDM has been created as a part of Decision Support System and is not (and will not be) available for public., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The presented work focuses on the assessment of the material performance of polyoxymethylene (POM)-based composites reinforced with the use of a biocarbon/basalt fiber system (BC/BF). The use of BC particles was aimed at eliminating mineral fillers (chalk, talc) by using fully biobased material, while basalt fibers can be considered an alternative to glass fibers (GF). All materials were prepared with the same 20% filler content, the differences concerned the (BC/BF) % ratio. Hybrid samples with (25/75), (50/50), and (75/25) ratios were prepared. Additionally, reference samples were also prepared (POM BC20% and POM BF20%.). Samples prepared by the injection molding technique were subjected to a detailed analysis of mechanical properties (static tensile and Charpy impact tests), thermomechanical characteristics (dynamic mechanical thermal analysis-DMTA, heat deflection temperature - HDT), and thermal and rheological properties (DSC, rotational rheometer tests). In order to assess fiber distribution within the material structure, the samples were scanned by a microtomography method (μCT). The addition of even a significant amount of BC particles did not cause excessive material brittleness, while the elongation and impact strength of all hybrid samples were very similar to the reference POM BF20% sample. The tensile modulus and strength values appear to be strictly dependent on the increasing BF fiber content. Thermomechanical analysis (DMTA, HDT) showed very similar heat resistance for all hybrid samples; the results did not differ from the values for the POM BF20 sample.

This study used self-administered survey data from seven high schools in Florida with a majority Black and/or Hispanic sample to examine transgender students' perceptions and experiences related to school climate in comparison to cisgender students. Using propensity score matching, a matched analytic sample was created of transgender and cisgender students ( n = 542, including 186 transgender youth). Adjusted weighted logistic regression models indicated that transgender students were significantly more likely to report ever being bullied at school, being bullied in the past 3 months, and not going to school ≥3 days during the past 30 days. Transgender students were significantly less likely to report feeling safe at school and having positive perceptions of all five school connectedness items compared to cisgender students. Recent bullying experiences moderated the association between transgender status and past month absences. Findings can inform potential roles for school nurses in improving school climate for transgender youth.

Purpose: Sexual and gender minority (SGM) youth face risks for negative sexual and reproductive health (SRH) outcomes; it is critical to provide these populations with health education that is both inclusive of and specific to their needs. We sought to characterize the strengths and weaknesses of SGM-related messages from web sites that address SRH for young people. We considered who is included, what topics are discussed, and how messages are framed., Methods: A systematic Google search and screening process was used to identify health promotion web sites with SRH content for adolescents and young adults. Using MAXQDA, we thematically coded and analyzed SGM content qualitatively., Results: Of 32 SRH web sites identified, 23 (71.9%) contained SGM content. Collectively, the sites included 318 unique SGM codes flagging this content. Approximately two-thirds of codes included messages that discussed SGM youth in aggregate (eg, lesbian, gay, bisexual, and transgender)-specific content about the diverse subpopulations within this umbrella term (eg, transgender youth) was more limited. In addition to SRH topics, most web sites had messages that addressed a broad array of other health issues including violence, mental health, and substance use (n = 17, 73.9%) and SGM-specific topics, for example coming out (n = 21, 91.3%). The former were often risk-framed, yet affirmational messages were common. Most web sites (n = 16; 69.6%) presented information for SGM youth both in stand-alone sections and integrated into broader content. Yet, integrated information was slightly more common (56.6% of all codes) than stand-alone content., Conclusions: Challenges of developing SRH content related to SGM youth include: (1) aggregate terms, which may not represent the nuances of sexual orientation and gender, (2) balancing risk versus affirmational messages, and (3) balancing stand-alone versus integrated content. However, SGM-related content also offers an opportunity to address diverse topics that can help meet the needs of these populations.

Background: Transgender adolescents are at increased risk for negative sexual health outcomes compared to their cisgender peers., Methods: Using data from 10,231 students from 7 high schools in a large, urban school district, our analysis compared sexual behaviors, referral to sexual health services by school staff, and use of sexual health services between transgender and cisgender students. We used propensity score matching to create a comparable sample of transgender and cisgender students and logistic regression models to examine how gender identity was associated with aforementioned outcomes., Results: Transgender students were more likely to have ever had sex, less likely to have used a condom at last sex, and more likely to have been referred for human immunodeficiency virus (HIV) testing, sexually transmitted disease (STD) testing, and other sexual health services than cisgender students. Transgender students were no more likely than cisgender students to have tested for HIV or STDs., Conclusions: These findings underscore the need for understanding the risk perceptions held by transgender students and for prevention efforts that are inclusive for all gender identities. Research is needed to understand if school-based sexual health interventions such as staff referrals for sexual health services are effective for transgender students., (Published 2020. This article is a U.S. Government work and is in the public domain in the USA.)

The paper discusses the preparation of polymer blends based on the polyethylene terephthalate copolymer/polycarbonate (GPET/PC). Materials have been prepared in order to assess their applicability in the fused deposition modeling (FDM) 3D printing process. The tested key feature was the thermomechanical resistance, measured by head deflection temperature (HDT) and Vicat softening temperature (VST), the mechanical tests and dynamic mechanical thermal analysis (DMTA) were also performed. A clear relationship between the increasing content of PC in the blend properties was observed. DMTA analysis revealed significant changes in the glass transition temperature, which indicates the miscibility of this type of polymer system. The mechanical tests indicate a clear trend of stiffness and strength improvement along with the increasing share of PC phase in the structure. The increase in impact strength is also clear, however, compared to the results for a pure PC, the results obtained for GPET/PC blends are significantly lower. As part of the research, reference samples based on polyethylene terephthalate homopolymer (PET) and composite samples with addition of 10% talc were also prepared. The structure analysis for PET/PC(50/50) samples did not show miscibility. However, due to the formation of the PET crystalline phase, the thermomechanical resistance of these materials was visibly higher. Scanning electron microscopy (SEM) analysis confirmed a high degree of compatibility of the GPET/PC blend structure as indicated by the lack of visible signs of phase separation. This phenomenon is not observed for PET/PC blends, which confirms the different thermomechanical interactions of both tested polymer systems.

Application of lignocellulosic fillers in the manufacturing of wood polymer composites (WPCs) is a very popular trend of research, however it is still rarely observed in the case of rotational molding. The present study aimed to analyze the impact of wheat bran content (from 2.5 wt.% to 20 wt.%) on the performance of rotationally-molded composites based on a linear low-density polyethylene (LLDPE) matrix. Microscopic structure (scanning electron microscopy), as well as physico-mechanical (density, porosity, tensile performance, hardness, rebound resilience, dynamic mechanical analysis), rheological (oscillatory rheometry) and thermo-mechanical (Vicat softening temperature) properties of composites were investigated. Incorporation of 2.5 wt.% and 5 wt.% of wheat bran did not cause significant deterioration of the mechanical performance of the material, despite the presence of 'pin-holes' at the surface. Values of tensile strength and rebound resilience were maintained at a very similar level, while hardness was slightly decreased, which was associated with the porosity of the structure. Higher loadings resulted in the deterioration of mechanical performance, which was also expressed by the noticeable rise of the adhesion factor. For lower loadings of filler did not affect the rheological properties. However, composites with 10wt.% and 20 wt.% also showed behavior suitable for rotational molding. The presented results indicate that the manufacturing of thin-walled products based on wood polymer composites via rotational molding should be considered a very interesting direction of research.

The study focuses on the development of polyoxymethylene (POM)/poly(lactic acid) (PLA) blends with increased impact and thermal resistance. The study was conducted in two phases; in the first part, a series of unmodified blends with PLA content of 25, 50, and 75 wt.% was prepared, while the second part focused on the modification of the PLA/POM (50/50) blends. An ethylene/butyl acrylate/glycidyl methacrylate terpolymer (E/BA/GMA) elastomer (EBA) was used to improve the impact strength of the prepared blends, while reactive blending was used to improve interfacial interactions. We used a multifunctional epoxy chain extender (CE) as the compatibilizer. Static tensile tests and notched Izod measurement were used to evaluate the mechanical performance of the prepared samples. The thermomechanical properties were investigated using dynamic mechanical thermal analysis (DMTA) analysis and heat deflection temperature (HDT)/Vicat softening temperature (VST) methods. The crystallinity was measured using differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXS) measurements, while the rheology was evaluated using a rotational rheometer. The paper also includes a structure analysis performed using the SEM method. The structural tests show partial miscibility of the POM/PLA systems, resulting in the perfect compatibility of both phases. The impact properties of the final blends modified by the EBA/CE system were found to be similar to pure POM resin, while the E modulus was visibly improved. Favorable changes were also noticeable in the case of the thermomechanical properties. The results of most of the conducted measurements and microscopic observations confirm the high efficiency of the reaction for PLA as well as for the modified POM/PLA mixtures.

The study presents a comparative analysis for two types of polymer fillers used during the processing of polypropylene by the injection molding technique. The aim of the study was to assess the usefulness of buckwheat husk waste as an alternative to the widely used wood fiber fillers. For this purpose, we prepared composite samples containing 10, 30 and 50 wt % of the filler, which were subjected to mechanical tests, thermal analysis, and structural observations in order to evaluate and compare their properties. Additionally, we evaluated the effectiveness of the composite system's compatibility by using maleic anhydride grafted polypropylene (PP-g-MA). The results of mechanical tests confirmed a more effective reinforcement mechanism for wood fibers; however, with the addition of PP-g-MA compatibilizer, these differences were significantly reduced: we observed a 14% drop for tensile modulus and 5% for strength. This suggests high susceptibility to this type of adhesion promoter, also confirmed by SEM observations. The paper also discusses rheological measurements conducted on a rotational rheometer, which allowed to confirm more favorable flow characteristics for composites based on buckwheat husks.

Objective: Limited information exists on whether associations between substance use behaviors (SUBs) and sexual risk behaviors (SRBs) vary by sexual identity., Methods: Data from the 2015 national Youth Risk Behavior Survey (n = 15,624), were analyzed to assess associations between SUBs (cigarette smoking, alcohol use, binge drinking, marijuana use, prescription drug misuse, injection drug use, illicit drug use) and SRBs (sexual activity, number of partners, condom use). Logistic regression models calculated adjusted prevalence ratios (aPR), stratified by sexual identity, and interaction effects for sexual identity were introduced to models to determine if associations varied by sexual identity., Results: All SUBs had significant associations with current sexual activity and 4+ sexual partners for both heterosexual and LGB students. No condom use during last sexual intercourse was significantly associated with all SUBs except alcohol use among heterosexual students, while no condom use was only significantly associated with injection drug use among LGB students. Associations between current sexual activity and SUBs were significantly stronger among heterosexual compared to LGB students for smoking (aPR = 2.39;95% CI:2.15,2.65 vs aPR = 1.49;95% CI:1.14,1.95), marijuana use (2.41;2.15,2.71 vs 1.86;1.58,2.19) and prescription drug misuse (2.10;1.93,2.28 vs 1.60;1.28,2.00). Associations between no condom use and SUBs were significantly stronger for heterosexual compared to LGB students only for smoking (1.32;1.16,1.50 vs 0.96;0.73,1.25) and marijuana use (1.22;1.07,1.38 vs 0.90;0.72,1.12)., Conclusions: The relationship between most SUBs and SRBs did not vary significantly by sexual identity. These findings underscore the importance coordinating school-based programs to prevent substance use and promote sexual health., (Published by Elsevier Ltd.)

Objective: This review synthesizes findings from the peer-reviewed evaluation literature on condom availability programs (CAPs) in secondary schools., Data Source: Peer-reviewed evaluation literature indexed in MEDLINE, EMBASE, PsychINFO, ERIC, CINAHL, Sociological Abstracts, SCOPUS, and POPLINE., Study Inclusion and Exclusion Criteria: Manuscripts had to be, written in English, and report evaluation data from a US school-based CAP., Data Extraction: Articles were coded independently by 2 authors. Discrepancies were resolved through open discussion., Data Synthesis: We grouped findings into outcome evaluation and process evaluation findings. Outcome evaluation findings included sexually transmitted infections (STIs), pregnancy rates, condom use, contraception use, sexual risk, and substance use. Process evaluation findings included awareness of CAPs, attitudes toward CAPs, attitudes toward condoms, and receipt of education and instruction., Results: Of the 138 citations reviewed, 12 articles published between 1995 and 2012 met the inclusion criteria, representing 8 programs. Evaluations indicate CAPs yield condom acquisition rates between 23% and 48%, have mixed results related to condom use, and are not associated with increases in sexual and other risk behaviors. One program found CAPs were associated with a decrease in a combined rate of chlamydia and gonorrhea. One program found no association between CAPs and unintended pregnancy. Students' attitudes toward CAPs were favorable and awareness was high., Conclusions: Condom availability programs are accepted by students and can be an appropriate and relevant school-based intervention for teens. Condom availability programs can increase condom use, but more evaluations are needed on CAP impact on rates of HIV, STIs, and unintended pregnancy.