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1.
Foods ; 13(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38731754

RESUMO

Despite the excellent oxygen barrier and biodegradability of polyvinyl alcohol (PVA), its poor physical properties owing to its inherent hydrophilicity limit its application. In this paper, we report a novel surface modification technique for PVA films, involving the control of the predrying conditions (i.e., amount of residual solvent) of the coated PVA film and adjusting the electrospinning process of hydrophobic polycaprolactone (PCL) nanofibers onto the PVA films. The residual solvent of the coated PVA film was varied by changing the predrying time. A shorter predrying time increased the residual solvent content significantly (p < 0.05) and the flexibility of the coated PVA film. Moreover, scanning electron microscopy depicted the improved physical binding of hydrophobic PCL nanofibers to the hydrophilic PVA surface with increased penetration depth to the PVA film with shorter drying times. The PVA/PCL composite films with different predrying times and electrospun PCL nanofibers exhibited an apparent increase in the contact angle from 8.3° to 95.1°. The tensile strength of the pure PVA film increased significantly (p < 0.05) from 7.5 MPa to 77.4 MPa and its oxygen permeability decreased from 5.5 to 1.9 cc/m2·day. Therefore, our newly developed technique is cost-effective for modifying the surface and physical properties of hydrophilic polymers, broadening their industrial applications.

2.
Int J Biol Macromol ; : 132495, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38763256

RESUMO

Incorporating starch, which is a potential biodegradable substitute for petroleum-based polymers, into conventional polymers is challenging owing to limitations in processability and weak-performing resulting materials. Herein, corn starch/polyvinyl alcohol (PVA) blend films (starch: PVA ratio of 50:50) were prepared via the solvent casting method using glycerol as a plasticizer and with varying concentrations of maleic acid as the crosslinking agent. Fourier transform infrared spectroscopy revealed the molecular interactions of the maleic acid crosslinker with the polymeric network of starch and PVA through an ester linkage. The properties of the films were strongly dependent on the maleic acid concentration. An increasing maleic acid concentration imparted hydrophobicity to the film; therefore, water swelling was significantly reduced, and water resistance was enhanced. The film containing 20 wt% maleic acid exhibited excellent barrier properties, with the lowest oxygen and water vapor transmission rates of 0.5 ±â€¯0.2 cc/m2⋅day and 232.3 ±â€¯5.4 g/m2⋅day, respectively. Moreover, the mechanical properties of the film improved with increasing crosslinking. This study demonstrates that the addition of maleic acid leads to an improvement in the overall performance of starch/PVA blend films. Therefore, maleic acid-crosslinked films can be used as barrier materials in food packaging applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38739419

RESUMO

Forming-free, low-voltage, and high-speed resistive switching is demonstrated in an Ag/oxygen-deficient vanadium oxide (VOx)/Pt device via the facilitated formation and rupture of Ag filaments. Direct current (DC) voltage sweep measurements exhibit forming-free switching from a high-resistance state (HRS) to a low-resistance state (LRS), called SET, at an average VSET of +0.23 V. The reverse RESET transition occurs at an average VRESET of -0.07 V with a low RESET current of <1 mA. Reversible switching operations are stable with an HRS/LRS resistance ratio >103 during repeated measurements for thousands of cycles. In pulse measurements, switching occurs within 100 ns at an amplitude of +1.5 V. Notably, a two-step resistance change is observed in the SET operation, where the resistance first partially decreases due to Ag+ ion accumulation in VOx and then further decreases to the LRS after hundreds of nanoseconds upon complete filament formation. The VOx layer deposited to be mostly amorphous with oxygen deficiency from V2O5 has abundant vacancies and expedites Ag+ ion migration, thus realizing forming-free, high-speed, and low-voltage switching. These characteristics of the facilitated Ag filament formation using the substoichiometric VOx layer are highly beneficial for use as stand-alone nonvolatile memory and in-memory computing elements.

4.
FEMS Microbiol Ecol ; 100(5)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38621717

RESUMO

The hydrographic variability in the fjords of Svalbard significantly influences water mass properties, causing distinct patterns of microbial diversity and community composition between surface and subsurface layers. However, surveys on the phytoplankton-associated bacterial communities, pivotal to ecosystem functioning in Arctic fjords, are limited. This study investigated the interactions between phytoplankton and heterotrophic bacterial communities in Svalbard fjord waters through comprehensive eDNA metabarcoding with 16S and 18S rRNA genes. The 16S rRNA sequencing results revealed a homogenous community composition including a few dominant heterotrophic bacteria across fjord waters, whereas 18S rRNA results suggested a spatially diverse eukaryotic plankton distribution. The relative abundances of heterotrophic bacteria showed a depth-wise distribution. By contrast, the dominant phytoplankton populations exhibited variable distributions in surface waters. In the network model, the linkage of phytoplankton (Prasinophytae and Dinophyceae) to heterotrophic bacteria, particularly Actinobacteria, suggested the direct or indirect influence of bacterial contributions on the fate of phytoplankton-derived organic matter. Our prediction of the metabolic pathways for bacterial activity related to phytoplankton-derived organic matter suggested competitive advantages and symbiotic relationships between phytoplankton and heterotrophic bacteria. Our findings provide valuable insights into the response of phytoplankton-bacterial interactions to environmental changes in Arctic fjords.


Assuntos
Bactérias , Processos Heterotróficos , Fitoplâncton , RNA Ribossômico 16S , RNA Ribossômico 18S , Estações do Ano , Fitoplâncton/genética , Fitoplâncton/metabolismo , Regiões Árticas , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Código de Barras de DNA Taxonômico , Estuários , Svalbard , Camada de Gelo/microbiologia , Ecossistema , DNA Bacteriano/genética , Biodiversidade , Microbiota/genética
5.
Arch Plast Surg ; 51(1): 42-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38425846

RESUMO

Background Increasing concerns regarding the safety of textured surface implants have resulted in surgeons transitioning from textured tissue expanders (TEs) to smooth TEs. Given this change has only recently occurred, this study evaluated outcomes between smooth and textured TEs. Methods Women who underwent two-stage breast reconstruction using TEs from 2013 to 2022 were included. TE-specific variables, perioperative information, pain scores, and complications were collected. Chi-squared, t -test, and linear regression analyses were performed. Results A total of 320 patients received a total of 384 textured and 152 smooth TEs. Note that 216 patients received bilateral reconstruction. TEs were removed in 9 cases. No significant differences existed between groups regarding comorbidities. Smooth TEs had a higher proportion of prepectoral placement ( p < 0.001). Smooth TEs had less fills (3 ± 1 vs. 4 ± 2, p < 0.001), shorter expansion periods (60 ± 44 vs. 90 ± 77 days, p < 0.001), smaller expander fill volumes (390 ± 168 vs. 478 ± 177 mL, p < 0.001), and shorter time to exchange (80 ± 43 vs. 104 ± 39 days, p < 0.001). Complication rates between textured and smooth TEs were comparable. Smooth TE had a greater proportion of TE replacements ( p = 0.030). On regression analysis, pain scores were more closely associated with age ( p = 0.018) and TE texture ( p = 0.046). Additional procedures at time of TE exchange ( p < 0.001) and textured TE ( p = 0.017) led to longer operative times. Conclusion As many surgeons have transitioned away from textured implants, our study shows that smooth TEs have similar outcomes to the textured alternatives.

6.
Environ Pollut ; 346: 123620, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387547

RESUMO

Highways, while vital for transportation, often lead to heightened air and noise pollution, adversely affecting nearby communities. This study delves into the effectiveness of highway capping, a sustainable urban development strategy, in addressing these environmental challenges, with a specific focus on the Bundang-Suseo Highway in South Korea. This study employed a multifaceted approach, incorporating on-road monitoring, in situ measurements, and vertical assessments using UAVs. Following the cap's installation, the area experienced more stable pollutant levels, marking a notable shift from the previously fluctuating conditions heavily influenced by the highway. In-depth in situ monitoring near the cap revealed significant reductions in noise and pollutants like UFP and BC. Furthermore, UAV monitoring captured these changes in pollutant levels at different altitudes. Notably, the installation of the highway cap led to increased PM2.5, PM10, and NO2 levels at ground level, but a decrease above the cap, emphasizing the critical importance of intentional highway cap design in enhancing urban air quality and reducing exposure to harmful pollutants. This research yields invaluable insights for urban planners, health authorities, and policymakers, aiding the precise identification of pollution-prone areas and advocating for improved highway cap design to enhance urban environments.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Ruído/prevenção & controle , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , Material Particulado/análise
7.
Food Chem ; 445: 138772, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38394908

RESUMO

The fabrication of coated papers using hydrophilic and biodegradable polymers is important for developing sustainable packaging materials with high barrier and superior mechanical properties. However, water, which is used as the solvent in the paper coating process using hydrophilic polymers, deforms the shape of the paper and deteriorates performance. Therefore, we propose a new coating process that treats Kraft paper (KP) with epichlorohydrin (ECH) as a binder before the coating process. Crosslinked polyvinyl alcohol is coated on the ECH-treated KP using a solution casting method. ECH maintains the shape of the paper and improves coating uniformity; significantly enhances interfacial interactions, which increases barrier properties and sealing strength; and extends the shelf life of biscuits by reducing oxygen and moisture permeability. An ecotoxicity test using Lolium multiflorum demonstrates an insignificant phytotoxicity level for the as-prepared coated papers. Thus, ECH-treated KP is a potential candidate for high-barrier food packaging.


Assuntos
Epicloroidrina , Água , Embalagem de Alimentos , Polímeros , Solventes
8.
Mar Pollut Bull ; 201: 116149, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38364527

RESUMO

The Arctic is severely affected by climate change and various forms of environmental pollution. Enriched with nutrients and light-absorbing compounds, the wildfire plume has the potential to affect biological carbon fixation and sequestration within the Arctic Ocean. In this study, we utilized satellite-derived oceanic data (phytoplankton and sea ice) and atmospheric reanalysis products (black carbon, BC, indicative of wildfire impact) to evaluate the effect of the pronounced increase in wildfires from 2019 to 2021 on the East Siberian Sea. During these years, chlorophyll-a levels rose by ∼213 % compared to the previous decadal average, which had notably lower wildfire activities. This increase in chlorophyll-a is attributable to the deposition of nitrogen from the wildfire plume. Concurrently, the period required for sea ice concentration to decrease by 25 % was on average âˆ¼ 10 days shorter than usual. This suggests that BC-induced acceleration of sea ice melting might extend the growing season for phytoplankton.


Assuntos
Incêndios Florestais , Oceanos e Mares , Regiões Árticas , Clorofila , Fitoplâncton , Clorofila A , Carbono , Nutrientes , Camada de Gelo
9.
ACS Appl Mater Interfaces ; 16(5): 6274-6283, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38282293

RESUMO

A novel approach to producing high-color-purity blue-light-emitting diodes based on single-crystalline Ruddlesden-Popper perovskites (RPPs) is reported. The utilization of a pure bromide composition eliminates any possibility of halide segregation, which can otherwise lead to undesired shifts in the emission wavelength or irreversible degradation of the spectral line width. Phase-pure PEA2MAPb2Br7 single crystals with a lateral size exceeding 1 cm2 can be synthesized using the inverse temperature crystallization method. To prepare RPP layers with a thickness of less than 50 nm, we employ a thinning process of the initially thick bulk crystals, followed by a dry-transfer process to place them onto a hole transport layer and an indium-tin-oxide-coated glass substrate. By utilizing polydimethylsiloxane as a handling layer, deformations of the bulk RPP crystal and exfoliated RPP layer, as well as the formation of defects such as pinholes, can be effectively suppressed. Subsequent depositions of an electron transport layer and a metal contact complete the fabrication of electroluminescence (EL) devices. The EL devices utilizing the single-crystalline RPP demonstrate excellent spectral stability across a broad range of the applied bias voltage spanning from 4.5 to 10 V, exhibiting a significantly narrow line width of 14 nm at an emission wavelength of 440 nm that can potentially cover 99.3% of the Rec. 2020 color gamut. The sharp EL emission spectrum can be effectively preserved, avoiding any broadening of the line width, by suppressing Joule heating throughout the device operation, in addition to the intrinsic stability of single-crystalline RPPs.

10.
Nano Lett ; 23(24): 11578-11585, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38051017

RESUMO

We report the growth of high-quality GaN epitaxial thin films on graphene-coated c-sapphire substrates using pulsed-mode metalorganic vapor-phase epitaxy, together with the fabrication of freestanding GaN films by simple mechanical exfoliation for transferable light-emitting diodes (LEDs). High-quality GaN films grown on the graphene-coated sapphire substrates were easily lifted off by using thermal release tape and transferred onto foreign substrates. Furthermore, we revealed that the pulsed operation of ammonia flow during GaN growth was a critical factor for the fabrication of high-quality freestanding GaN films. These films, exhibiting excellent single crystallinity, were utilized to fabricate transferable GaN LEDs by heteroepitaxially growing InxGa1-xN/GaN multiple quantum wells and a p-GaN layer on the GaN films, showing their potential application in advanced optoelectronic devices.

11.
Environ Res ; 239(Pt 1): 117217, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37775002

RESUMO

Marine organic aerosols play crucial roles in global climatic systems. However, their chemical properties and relationships with various potential organic sources still need clarification. This study employed high-resolution mass spectrometry to investigate the identity, origin, and transportation of organic aerosols in pristine Antarctic environments (King Sejong Station; 62.2°S, 58.8°W), where complex ocean-cryosphere-atmosphere interactions occur. First, we classified the aerosol samples into three clusters based on their air mass transport history. Next, we investigated the relationship between organic aerosols and their potential sources, including organic matter dissolved in the open ocean, coastal waters, and runoff waters. Cluster 1 (C1), in which the aerosols mainly originated from the open ocean area (i.e., pelagic zone-influenced), exhibited a higher abundance of lipid-like and protein-like organic aerosols than cluster 3 (C3), with ratios 1.8- and 1.6-times higher, respectively. In contrast, C3, characterized by longer air mass retention over sea ice and land areas (i.e., inshore-influenced), had higher lignin- and condensed aromatic structures (CAS)-like organic aerosols by 2.2- and 3.4-times compared to C1. Cluster 2 (C2) has intermediate characteristics between C1 and C3 concerning the chemical properties of the aerosols and air mass travel history. Notably, the chemical properties of the aerosols assigned to C1 are closely related to those of phytoplankton-derived organics enriched in the open ocean. In contrast, those of C3 are comparable to those of terrestrial plant-derived organics enriched in coastal and runoff waters. These findings help evaluate the source-dependent properties of organic aerosols in changing Antarctic environment.


Assuntos
Atmosfera , Camada de Gelo , Regiões Antárticas , Aerossóis , Lignina
12.
Sci Rep ; 13(1): 9592, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37311855

RESUMO

Memristive devices have been explored as electronic synaptic devices to mimic biological synapses for developing hardware-based neuromorphic computing systems. However, typical oxide memristive devices suffered from abrupt switching between high and low resistance states, which limits access to achieve various conductance states for analog synaptic devices. Here, we proposed an oxide/suboxide hafnium oxide bilayer memristive device by altering oxygen stoichiometry to demonstrate analog filamentary switching behavior. The bilayer device with Ti/HfO2/HfO2-x(oxygen-deficient)/Pt structure exhibited analog conductance states under a low voltage operation through controlling filament geometry as well as superior retention and endurance characteristics thanks to the robust nature of filament. A narrow cycle-to-cycle and device-to-device distribution were also demonstrated by the filament confinement in a limited region. The different concentrations of oxygen vacancies at each layer played a significant role in switching phenomena, as confirmed through X-ray photoelectron spectroscopy analysis. The analog weight update characteristics were found to strongly depend on the various conditions of voltage pulse parameters including its amplitude, width, and interval time. In particular, linear and symmetric weight updates for accurate learning and pattern recognition could be achieved by adopting incremental step pulse programming (ISPP) operation scheme which rendered a high-resolution dynamic range with linear and symmetry weight updates as a consequence of precisely controlled filament geometry. A two-layer perceptron neural network simulation with HfO2/HfO2-x synapses provided an 80% recognition accuracy for handwritten digits. The development of oxide/suboxide hafnium oxide memristive devices has the capacity to drive forward the development of efficient neuromorphic computing systems.

13.
Sci Total Environ ; 879: 163020, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36965732

RESUMO

In two Icelandic Sea spring blooms (May 2018 and 2019) in the North Atlantic Ocean (62.9-68.0°N, 9.0-28.0°W), chlorophyll-a and dimethylsulfoniopropionate (DMSP) concentrations and DMSP lyase activity (the DMSP-to-dimethyl sulfide (DMS) conversion efficiency) were measured at 67 stations, and the hourly atmospheric DMS mixing ratios were concurrently measured only in May 2019 at Storhofdi on Heimaey Island, located south of Iceland (63.4°N, 20.3°W). The ocean parameters for biology (i.e., chlorophyll-a, DMSP, and DMSP lyase activity) were broadly associated in distribution; however, the statistical significance of the association differed among four ocean domains and also between 2018 and 2019. Specifically, the widespread dominance of Phaeocystis, coccolithophores, and dinoflagellates (all rich in DMSP and high in DMSP lyase activity) across the study area is a compelling indication that variations in DMSP-rich phytoplankton were likely a main cause of the variations in statistical significance. For all the ocean domains defined here, we found that the DMS production capacity (calculated using the exposures of air masses to ocean biology prior to their arrivals at Heimaey and the atmospheric DMS mixing ratios of those air masses at Heimaey) was surprisingly consistent with in situ ocean S data (i.e., DMSP and DMSP lyase activity). Our study shows that the proposed computational approach enabled the detection of changes in DMS production and emission in association with changes in ocean primary producers.


Assuntos
Fitoplâncton , Compostos de Enxofre , Oceano Atlântico , Clorofila , Clorofila A , Islândia , Água do Mar , Sulfetos/análise
14.
Sci Total Environ ; 879: 163070, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36990237

RESUMO

The study of airborne chemical markers is crucial for identifying sources of aerosols, and their atmospheric processes of transport and transformation. The investigation of free amino acids and their differentiation between the L- and D- enantiomers are even more important to understand their sources and atmospheric fate. Aerosol samples were collected with a high-volume sampler with cascade impactor at Mario Zucchelli Station (MZS) on the coast of the Ross Sea (Antarctica) for two summer campaigns (2018/19 and 2019/20). The total mean concentration of free amino acids in PM10 was 4 ± 2 pmol m-3 for both campaigns and most of free amino acids were distributed in fine particles. The coarse mode of airborne D-Alanine and dimethylsufoniopropionate in seawater showed a similar trend during both Antarctic campaigns. Thus, the study of D/L Ala ratio in fine, coarse and PM10 fractions indicated the microlayer as the local source. This paper demonstrated that free amino acids follow the trend of DMS and MSA release occurred in the Ross Sea, confirming their applicability as markers for phytoplankton bloom also in paleoclimatic studies.

15.
Sci Total Environ ; 878: 162969, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36958547

RESUMO

Sea spray aerosol (SSA) particles strongly influence clouds and climate but the potential impact of ocean microbiota on SSA fluxes is still a matter of active research. Here-by means of in situ ship-borne measurements-we explore simultaneously molecular-level chemical properties of organic matter (OM) in oceans, sea ice, and the ambient PM2.5 aerosols along a transect of 15,000 km from the western Pacific Ocean (36°13'N) to the Southern Ocean (75°15'S). By means of orbitrap mass spectrometry and optical characteristics, lignin-like material (24 ± 5 %) and humic material (57 ± 8 %) were found to dominate the pelagic Pacific Ocean surface, while intermediate conditions were observed in the Pacific-Southern Ocean waters. In the marine atmosphere, we found a gradient of features in the aerosol: lignin-like material (31 ± 9 %) dominating coastal areas and the pelagic Pacific Ocean, whereas lipid-like (23 ± 16 %) and protein-like (11 ± 10 %) OM controlled the sympagic Southern Ocean (sea ice-influence). The results of this study showed that the OM composition in the ocean, which changes with latitude, affects the OM in aerosol compositions in the atmosphere. This study highlights the importance of the global-scale OM monitoring of the close interaction between the ocean, sea ice, and the atmosphere. Sympagic primary marine aerosols in polar regions must be treated differently from other pelagic-type oceans.

16.
Plast Reconstr Surg ; 152(3): 488e-498e, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36847664

RESUMO

BACKGROUND: The neurodevelopmental effects of skull asymmetry and orthotic helmet therapy for deformational plagiocephaly (DP) have had limited investigation. This study assessed the long-term neurocognitive outcomes in patients with DP and their association with orthotic helmet therapy and head shape abnormality. METHODS: A total of 138 school-age children with a history of DP, 108 of whom received helmet therapy, were tested with a neurocognitive battery assessing academic achievement, intelligence quotient, and visual-motor function. Severity of presenting plagiocephaly was calculated using anthropometric and photometric measurements. Analysis of covariance was used to compare outcomes between helmeted and nonhelmeted cohorts, unilateral plagiocephaly and concomitant brachycephaly, and left-sided and right-sided plagiocephaly. The association between severity of plagiocephaly and neurocognitive outcome was assessed through a residualized change approach. RESULTS: There were no significant differences in neurocognitive outcomes between the helmeted and nonhelmeted DP cohorts or the unilateral plagiocephaly and brachycephaly cohorts. Participants with left-sided DP had significantly lower motor coordination scores than participants with right-sided DP (84.8 versus 92.7; effect size = -0.50; P = 0.03). There was a significant laterality by cephalic index interaction, with a negative association between cephalic index and reading comprehension and spelling for participants with left-sided DP. No significant associations were found between severity of presenting or posttreatment deformity and neurocognitive outcome. CONCLUSIONS: Pretreatment and posttreatment severity of plagiocephaly were not correlated with neurocognitive function at school age. Helmet therapy was not associated with better or worse long-term neurocognitive function. However, participants with left-sided DP demonstrated worse neurocognitive outcomes than participants with right-sided DP in the domains of motor coordination and some types of academic achievement. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.


Assuntos
Craniossinostoses , Plagiocefalia não Sinostótica , Plagiocefalia , Criança , Humanos , Lactente , Plagiocefalia não Sinostótica/complicações , Plagiocefalia não Sinostótica/terapia , Resultado do Tratamento , Dispositivos de Proteção da Cabeça , Plagiocefalia/terapia , Craniossinostoses/complicações , Craniossinostoses/terapia , Aparelhos Ortopédicos
17.
Cleft Palate Craniofac J ; 60(3): 274-279, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34787505

RESUMO

OBJECTIVE: Several severity metrics have been developed for metopic craniosynostosis, including a recent machine learning-derived algorithm. This study assessed the diagnostic concordance between machine learning and previously published severity indices. DESIGN: Preoperative computed tomography (CT) scans of patients who underwent surgical correction of metopic craniosynostosis were quantitatively analyzed for severity. Each scan was manually measured to derive manual severity scores and also received a scaled metopic severity score (MSS) assigned by the machine learning algorithm. Regression analysis was used to correlate manually captured measurements to MSS. ROC analysis was performed for each severity metric and were compared to how accurately they distinguished cases of metopic synostosis from controls. RESULTS: In total, 194 CT scans were analyzed, 167 with metopic synostosis and 27 controls. The mean scaled MSS for the patients with metopic was 6.18 ± 2.53 compared to 0.60 ± 1.25 for controls. Multivariable regression analyses yielded an R-square of 0.66, with significant manual measurements of endocranial bifrontal angle (EBA) (P = 0.023), posterior angle of the anterior cranial fossa (p < 0.001), temporal depression angle (P = 0.042), age (P < 0.001), biparietal distance (P < 0.001), interdacryon distance (P = 0.033), and orbital width (P < 0.001). ROC analysis demonstrated a high diagnostic value of the MSS (AUC = 0.96, P < 0.001), which was comparable to other validated indices including the adjusted EBA (AUC = 0.98), EBA (AUC = 0.97), and biparietal/bitemporal ratio (AUC = 0.95). CONCLUSIONS: The machine learning algorithm offers an objective assessment of morphologic severity that provides a reliable composite impression of severity. The generated score is comparable to other severity indices in ability to distinguish cases of metopic synostosis from controls.


Assuntos
Inteligência Artificial , Craniossinostoses , Humanos , Lactente , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Tomografia Computadorizada por Raios X , Estudos Retrospectivos
18.
Plast Reconstr Surg ; 150(6): 1309-1317, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126215

RESUMO

BACKGROUND: Although nonsyndromic craniosynostosis has been associated with neurodevelopmental sequelae, a lesser amount of emphasis has been placed on the need for related supportive services. This study assessed the prevalence of such services among children surgically treated for nonsyndromic craniosynostosis and identified predictors of service use. METHODS: Parents of children with nonsyndromic craniosynostosis were recruited from an online craniosynostosis support network and surveyed regarding their child's use of various outpatient and school-based services. Multiple stepwise regression was performed to identify predictive variables for each type of intervention. RESULTS: A total of 100 surveys were completed. Of these, 45 percent of parents reported use of one or more outpatient support services for their children. The most commonly used services were speech therapy (26.0 percent) and physical therapy (22.0 percent), although the use of services such as psychology/psychiatry increased among older children (18.2 percent in children aged 6 to 10 years). Among school-age children ( n = 49), the majority of parents (65.3 percent) reported school-based assistance for their children, most commonly for academic (46.9 percent) or behavioral (42.9 percent) difficulties. Significant predictive variables ( p < 0.05 following stepwise regression) for increases in various outpatient and school-based services included male sex, African American race/ethnicity, higher parental income, the presence of siblings in the household, increased age at the time of surgery, and sagittal synostosis. CONCLUSIONS: Parents of children with nonsyndromic craniosynostosis reported frequent use of outpatient and school-based supportive services throughout childhood. These services may incur a significant burden of care on families. The multifactorial nature of predictive models highlights the importance of cross-disciplinary collaboration to address each child's longitudinal needs.


Assuntos
Craniossinostoses , Pacientes Ambulatoriais , Criança , Humanos , Masculino , Adolescente , Pais , Instituições Acadêmicas , Serviços de Saúde Escolar , Craniossinostoses/cirurgia
19.
J Craniofac Surg ; 33(5): 1294-1298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36041136

RESUMO

ABSTRACT: With the increase in the elderly population in the United States, the number of people seeking care for trauma injuries is expected to increase. However, nationwide studies on epidemiological profile of elderly facial fractures remain sparse. The authors present the epidemiological measures of elderly facial fractures on national scale. Characteristics of facial fractures among younger adults (18-64 years old) and the elderly population (65-74 years old, 75-84 years old and 85 years and above) have been examined using the 2016 American College of Surgeons-Trauma Quality Improvement Program databank. Variables studied included facial fracture patterns, mechanisms of injury, treatment variables, and demographic descriptive data. Of 104,183 elderly trauma patients, 3415 presented with facial fractures, making up 3.3% (versus 6.5% in younger adults). Majority of facial fractures in 85 and over group (60.7%) were experienced by females, compared to only 19.5% in the younger adult group. Most common mechanism of injury in the elderly was falls, versus motor vehicle trauma in younger adults. The most common type of facial fractures among both groups were nasal fractures. Elderly patients presented with fewer zygoma, mandibular and nasal fractures when compared to younger adults, whereas showing more maxillary/malar and orbital bone fractures. Elderly patients experienced less operative management (4.3%-8.2%) compared to younger adults (15.6%). Concurrently, mortality rates were higher in the elderly patients (9.9%-11.8%) when compared to the younger adults (8.0%). Elderly patients presented with different causes of injury, distribution of fractures, and rates of operative management compared to younger adults.


Assuntos
Ossos Faciais , Fraturas Cranianas , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Ossos Faciais/lesões , Ossos Faciais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Melhoria de Qualidade , Fraturas Cranianas/epidemiologia , Fraturas Cranianas/cirurgia , Estados Unidos/epidemiologia , Adulto Jovem
20.
RSC Adv ; 12(29): 18547-18558, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35799917

RESUMO

Bipolar threshold switching characteristics, featuring volatile transition between the high-resistance state (HRS) at lower voltage than threshold voltage (V th) and the low-resistance state (LRS) at higher voltage irrespective of the voltage polarity, are investigated in the Nb(O)/NbO x /Nb(O) devices with respect to deposition and post-annealing conditions of NbO x layers. The device with NbO x deposited by reactive sputtering with 12% of O2 gas mixed in Ar shows threshold switching behaviors after electroforming operation at around +4 V of forming voltage (V f). On the other hand, electroforming-free threshold switching is achieved from the device with NbO x deposited in the reduced fraction of 7% of O2 gas and subsequently annealed at 250 °C in vacuum, thanks to the increase of the amount of conducting phases within the NbO x layer. Threshold switching is thought to be driven by the formation of a temporally percolated filament composed of conducting NbO and NbO2 phases in the NbO x layer, which were formed as a result of the interaction with Nb electrodes such as oxygen ion migration either by annealing or electrical biasing. The presence of a substantial amount of oxygen in the Nb electrodes up to ∼40 at%, named Nb(O) herein, would alleviate excessive migration of oxygen and consequent overgrowth of the filament during operation, thus enabling reliable threshold switching. These results demonstrate a viable route to realize electroforming-free threshold switching in the Nb(O)/NbO x /Nb(O) devices by controlling the contents of conducting phases in the NbO x layer for the application to selector devices in high-density crossbar memory and synapse array architectures.

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