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We report ultrafast reflectivity measurements of the dynamics of the order parameter of the charge density wave (CDW) in TbTe3under anisotropic strain. We observe an increase in the frequency of the amplitude mode with increasing tensile strain along thea-axis (which drives the lattice intoa > c, withaandcthe lattice constants), and similar behavior for tensile strain alongc(c > a). This suggests that both strains stabilize the corresponding CDW order and further support the near equivalence of the CDW phases oriented ina- andc-axis, in spite of the orthorhombic space group. The results were analyzed within the time-dependent Ginzburg-Landau framework, which agrees well with the reflectivity dynamics. Our study presents an ultrafast approach to assess the stability of phases and order parameter dynamics in strained systems.
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The lowest-lying fundamental excitation of an incommensurate charge-density-wave material is believed to be a massless phason-a collective modulation of the phase of the charge-density-wave order parameter. However, long-range Coulomb interactions should push the phason energy up to the plasma energy of the charge-density-wave condensate, resulting in a massive phason and fully gapped spectrum1. Using time-domain terahertz emission spectroscopy, we investigate this issue in (TaSe4)2I, a quasi-one-dimensional charge-density-wave insulator. On transient photoexcitation at low temperatures, we find the material strikingly emits coherent, narrowband terahertz radiation. The frequency, polarization and temperature dependences of the emitted radiation imply the existence of a phason that acquires mass by coupling to long-range Coulomb interactions. Our observations underscore the role of long-range interactions in determining the nature of collective excitations in materials with modulated charge or spin order.
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We report ultrafast x-ray scattering experiments of the quasi-1D charge density wave (CDW) material (TaSe_{4})_{2}I following ultrafast infrared photoexcitation. From the time-dependent diffraction signal at the CDW sidebands we identify a 0.11 THz amplitude mode derived primarily from a transverse acoustic mode of the high-symmetry structure. From our measurements we determine that this mode interacts with the valence charge indirectly through another collective mode, and that the CDW system in (TaSe_{4})_{2}I has a composite nature supporting multiple dynamically active structural degrees of freedom.
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Topological magnonic materials have attracted much interest because of the potential for dissipationless spintronic applications. Pyrochlore iridates are theoretically regarded as good candidates for designing topological magnon bands. However, experimental identification of topological magnon bands in pyrochlore iridates remains elusive. We explored this possibility in Y_{2}Ir_{2}O_{7} using Raman spectroscopy to measure both the single-magnon excitations and anomalous phonon shifts. From the single-magnon energies and tight-binding model calculations concerning the phonons, we determined the key parameters in the spin Hamiltonian. These confirm that Y_{2}Ir_{2}O_{7} hosts a nontrivial magnon band topology distinct from other pyrochlore iridate compounds. Our work demonstrates that pyrochlore iridates constitute a system in which the magnon band topology can be tailored and that Raman spectroscopy is a powerful technique to explore magnon band topology.
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The potential role of visceral adipose tissue (VAT) as a prognostic factor in patients with diffuse large B cell lymphoma (DLBCL) treated with frontline rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP) immunochemotherapy was explored. Total adipose tissue and VAT were measured by analyzing positron emission tomography (PET)/computed tomography (CT) images obtained during the initial staging of patients with DLBCL. The VAT ratio was calculated as follows: VAT ratio = VAT area/total adipose tissue area. Body mass index (BMI), sex, and International Prognostic Index (IPI) were also incorporated as co-variates in the final model of multivariate Cox regression analysis for survival. A total of 156 patients with DLBCL, who were treated with frontline R-CHOP, were enrolled in our study. The median patient age was 61 years, and 81 patients were male (51.9 %). The median cycle of R-CHOP was six. The IPI risk group was a strong prognostic factor for progression-free survival (PFS) and overall survival (OS) (p < 0.001). Obese BMIs were an independent prognostic factor for PFS, but not for OS in multivariate analyses, compared to patients with normal BMIs (HR = 0.43, 95 % CI = 0.19-0.98, and p = 0.046 for PFS). A high VAT ratio (third tertile) was an independent adverse prognostic factor for PFS and OS in multivariate analyses (HR = 2.87 and 2.66, 95 % CI = 1.30-6.32 and 1.30-5.44, and p = 0.009 and 0.007 for PFS and OS, respectively). VAT ratio was an independent prognostic factor for patients with DLBCL treated with first-line R-CHOP; thus, additional large prospective studies are warranted.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Grasa Intraabdominal/efectos de los fármacos , Grasa Intraabdominal/patología , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Humanos , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Pronóstico , Estudios Retrospectivos , Rituximab , Tasa de Supervivencia/tendencias , Resultado del Tratamiento , Vincristina/administración & dosificaciónRESUMEN
OBJECTIVE: We investigated family caregivers' awareness of disease status and attitude toward disclosure of disease progression compared with those of cancer patients and explored the potential association between family caregivers' attitudes and patients' quality of life (QOL). METHODS: We carried out a survey using self-administered questionnaires answered by pairs of family caregivers and patients diagnosed with advanced cancer (n = 136 pairs). To assess patients' QOL, we used the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire. RESULTS: More than half of family caregivers (54%) did not have full knowledge of patients' advanced stage and goal of therapy. Positive attitudes toward disclosure were less common in family caregivers than in patients (59.4% and 85.4%, respectively; p < 0.01). The family caregivers' positive attitudes toward disclosure were inversely associated with patients' low functional scores (emotion [p = 0.04] and cognition [p = 0.02]) and high symptom scores (nausea and vomiting, pain, and insomnia; p < 0.05). However, in most QOL scales, patients' attitudes were not significantly associated with functioning and symptom scores. CONCLUSIONS: A large portion of family caregivers may not know the patients' exact status. This study also suggests that the family caregivers' attitudes may differ from patients' and may be associated with patients' QOL.
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Actitud Frente a la Salud , Cuidadores , Neoplasias/psicología , Calidad de Vida , Revelación de la Verdad , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Planificación de Atención al PacienteRESUMEN
This study aimed to analyze the effect of the height of the proximal axial wall of the prepared tooth and the distance between the adjacent tooth and the prepared tooth on the scan accuracy of intraoral scanners. Ten working casts with maxillary first molars prepared to receive zirconia crowns were randomly obtained from a dental clinic. Each of the 10 casts was scanned using two intraoral scanners (i700; MEDIT and CS3600; Carestream; computer-aided design [CAD] test model, CTM; N = 15 per working cast) 15 times per scanner. Individual dies of the prepared teeth were fabricated, and high-precision scan data were acquired using a laboratory scanner (CAD reference model, CRM; N = 1). CTMs were aligned relative to the prepared tooth of CRMs by using three-dimensional inspection software (Ver 2018.1.0; Control X; 3D Systems). Data were statistically analyzed using an independent t-test and one-way analysis of variance for between-group comparisons (α = 0.05). The inaccuracy in the proximal regions (mesial or distal) of the prepared tooth was higher than that in the buccal and lingual regions (p < 0.05). The scan accuracy was not correlated with the variables when the distance between the adjacent tooth and the prepared tooth was ≥2.0 mm and the height of the proximal axial wall of the prepared tooth was <3.0 mm (p > 0.05). Therefore, an excellent scan accuracy can be obtained using an intraoral scanner when the distance between the adjacent tooth and the prepared tooth is ≥2.0 mm and the proximal axial wall height of the prepared tooth is <3.0 mm.
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OBJECTIVES: This study aimed to evaluate the marginal and internal fit of zirconia crowns were fabricated using scan data from an intraoral optical coherence tomography (OCT) scanner and an intraoral scanner (IOS) for scanning the subgingival finish line. METHODS: An extracted maxillary left central incisor was prepared for a zirconia crown. The prepared tooth was placed in artificial gingiva, created using silicone with a refractive index similar to that of the tooth, ensuring a subgingival depth of 0.50 to 0.70 mm from the labial finish line. Scanning data were obtained from four types of models as follows. (1) CAD reference model (CRM) excluding the gingiva and scanned using a laboratory scanner. (2) IOS group excluding the gingiva (IOS only, IOSO group). (3) IOS group with scanned attached artificial (IOS with gingiva, IOSG group). (4) OCT post-processed data of the subgingival finish line and IOSG data (OCT group). Zirconia crowns were fabricated based on these data, and their marginal and internal fit were evaluated using the silicone replica technique. Statistical analyses were conducted using one-way and two-way ANOVA (α = 0.05). RESULTS: The OCT group exhibited a significantly smaller marginal gap than the IOSG group (P < 0.05). The marginal fit of the OCT group did not significantly differ from that of the CRM group (P > 0.05). The IOSG group exhibited a significantly larger chamfer gap, while both the IOSG and OCT groups had significantly larger axial gaps. Furthermore, the OCT group showed a significantly larger incisal gap (P < 0.05). CONCLUSIONS: An intraoral OCT system can enhance the fabrication accuracy of zirconia crowns by achieving superior marginal fit for crowns with subgingival finish lines. CLINICAL SIGNIFICANCE: The use of an IOS for subgingival finish lines without gingival displacement cords may result in a suboptimal marginal fit. However, integrating OCT technology can effectively address this issue, leading to improved clinical outcomes.
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PURPOSE: This study aimed to evaluate the clinical performance of implant-assisted removable partial dentures (IARPD) with surveyed crowns, also known as implant-crown-retained removable partial dentures (ICRPDs). MATERIALS AND METHODS: Electronic searches of MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials, the Web of Science, and the Korea Citation Index were performed according to the established search terms for ICRPD. A literature search was conducted for studies published in English or Korean until September 2023, using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. RESULTS: A total of 216 journals were searched, and 31 eligible studies were selected based on the inclusion and exclusion criteria. One systematic review included five case reports of ICRPD. Nine retrospective studies evaluated implant survival/success rate, implant failure cases, marginal bone loss, periodontal status, clinical complications, and patient satisfaction. Twenty-one case reports published in Korea showed good prognoses. CONCLUSION: According to the findings of this systematic review, ICRPD has a reasonable survival/success rate, minimal bone loss, and high patient satisfaction.
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This clinical study aimed to predict the learning curve of wireless and wired intraoral scanners (IOSs) and to compare the reduction patterns of working time. Overall, 14 participants were enrolled in the study. The intraoral scanning procedure was repeated four times, each using wireless and wired IOSs (i700; MEDIT). The work time from the first to the 600th iterations was predicted using the Wright model. Regarding statistical analysis, the Mann-Whitney U-test was performed for comparison between wireless and wired IOSs and between groups with and without an IOS usage experience, and the Friedman test was performed to evaluate the time reduction (α = 0.05). There was a significant difference between wireless and wired IOSs in the first (P = 0.008) and the third (P = 0.035) iterations. Moreover, the time for 600 iterations was statistically significantly different between wireless and wired IOSs (P < 0.05); however, there was no significant difference after the sixth iteration (e.g., seventh iteration: P = 0.062). In wireless IOS, no significant difference was found between participants with and without an IOS usage experience after the 34th iteration (P = 0.053). The difference in the learning effect between wireless and wired IOSs can be overcome by initial learning; however, an IOS usage experience can affect the learning time of wireless IOSs.
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Imagenología Tridimensional , Curva de Aprendizaje , Humanos , Diseño Asistido por Computadora , Modelos Dentales , Estadísticas no ParamétricasRESUMEN
PURPOSE: Accuracy of image matching between resting and smiling facial models is affected by the stability of the reference surfaces. This study aimed to investigate the morphometric variations in subdivided facial units during resting, posed and spontaneous smiling. MATERIALS AND METHODS: The posed and spontaneous smiling faces of 33 adults were digitized and registered to the resting faces. The morphological changes of subdivided facial units at the forehead (upper and lower central, upper and lower lateral, and temple), nasal (dorsum, tip, lateral wall, and alar lobules), and chin (central and lateral) regions were assessed by measuring the 3D mesh deviations between the smiling and resting facial models. The one-way analysis of variance, Duncan post hoc tests, and Student's t-test were used to determine the differences among the groups (α = .05). RESULTS: The smallest morphometric changes were observed at the upper and central forehead and nasal dorsum; meanwhile, the largest deviation was found at the nasal alar lobules in both the posed and spontaneous smiles (P < .001). The spontaneous smile generally resulted in larger facial unit changes than the posed smile, and significant difference was observed at the alar lobules, central chin, and lateral chin units (P < .001). CONCLUSION: The upper and central forehead and nasal dorsum are reliable areas for image matching between resting and smiling 3D facial images. The central chin area can be considered an additional reference area for posed smiles; however, special cautions should be taken when selecting this area as references for spontaneous smiles.
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PATIENTS: The patient was a 32-year-old man who underwent amalgam restoration of the mandibular right second molar. An amalgam restoration fracture was diagnosed by intraoral optical coherence tomography (OCT), and pulp exposure was examined during cavity preparation. Subsequently, a definitive ceramic restoration was fabricated, and the marginal fit in the oral cavity was evaluated using the OCT system. DISCUSSION: The existing OCT system cannot acquire images inside the oral cavity because of the large probe size. However, the proposed intraoral OCT system can access the prostheses in the mandibular right second molar. Therefore, dental diagnosis for restoration treatment with dental prosthesis fracture, marginal gap, and pulp exposure after tooth preparation is possible using the proposed intraoral OCT system. CONCLUSIONS: The use of the intraoral OCT system improved dental diagnosis by allowing the dentist to confirm quantitative values through cross-sectional images, rather than that by determining a treatment plan after visual dental diagnosis.
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Incrustaciones , Tomografía de Coherencia Óptica , Humanos , Adulto , Tomografía de Coherencia Óptica/métodos , Diente Molar , Preparación de la Cavidad Dental , BocaRESUMEN
OBJECTIVE: Along with rapid economic growth, the United Arab Emirates (UAE) has undergone enormous sociocultural changes. Consequently, sociocultural and psychological factors, along with malnutrition and physical inactivity, have contributed to the high obesity rate. The objective of this study is to assess the long-term impact of these new emerging factors on obesity among women in the UAE via mathematical modeling. METHODS: A differential equation model was developed considering psychological/social factors in population dynamics. It predicts the long-term prevalence of obesity among women in the UAE under these factors by 2070. Computer simulations and a sensitivity analysis of the model were conducted to measure the impact of these factors on obesity. RESULTS: The model predicts the following: 80.07% of female UAE nationals will become overweight or have obesity and 60.19% will have obesity by 2070, and the population with abnormal eating behavior will increase to 15% by 2070. Psychological/social factors aggravate the obesity problems and can cause abnormal eating behavior to develop with little effect on weight reduction. CONCLUSIONS: The obesity rate of female UAE nationals will continue to rise by 2070. Rising abnormal eating behavior caused by psychological/social factors is an emerging issue and should be recognized as a sign of escalating obesity problems in the UAE.
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Obesidad , Interacción Social , Femenino , Humanos , Obesidad/epidemiología , Prevalencia , Emiratos Árabes Unidos/epidemiologíaRESUMEN
The aim of this study is to evaluate the wear volume of interim crowns fabricated using digital light processing 3D printing according to the printing angle. A total of five patients undergoing the placement of a single crown on the mandibular molar were included. Interim crowns were fabricated directly in the oral cavity using the conventional method. A digital light processing 3D printer was then used to fabricate crowns with build angles of 0, 45, and 90 degrees. Therefore, four fabricated interim crowns were randomly delivered to the patients, and each was used for one week. Before and after use, the intaglio surfaces of the interim crowns were scanned using a 3D scanner. The volume changes before and after use were measured, and changes in the height of the occlusal surface were evaluated using the root mean square value. Data normality was verified by statistical analysis, and the wear volume in each group was evaluated using a one-way analysis of variance and Tukey's honestly significant difference test (α = 0.05). Compared with the RMS values of the conventional method (11.88 ± 2.69 µm) and the 3D-printing method at 0 degrees (12.14 ± 2.38 µm), the RMS values were significantly high at 90 degrees (16.46 ± 2.39 µm) (p < 0.05). Likewise, there was a significant difference in the change in volume between the groups (p = 0.002), with a significantly higher volume change value at 90 degrees (1.74 ± 0.41 mm3) than in the conventional method (0.70 ± 0.15 mm3) (p < 0.05). A printing angle of 90 degrees is not recommended when interim crowns are fabricated using digital light processing 3D printing.
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PURPOSE: This study investigated the accuracy of full-arch intraoral scans obtained by various scan strategies with the segmental scan and merge methods. MATERIALS AND METHODS: Seventy intraoral scans (seven scans per group) were performed using 10 scan strategies that differed in the segmental scan (1, 2, or 3 segments) and the scanning motion (straight, zigzag, or combined). The three-dimensional (3D) geometric accuracy of scan images was evaluated by comparison with a reference image in an image analysis software program, in terms of the arch shape discrepancies. Measurement parameters were the intermolar distance, interpremolar distance, anteroposterior distance, and global surface deviation. One-way analysis of variance and Tukey honestly significance difference post hoc tests were carried out to compare differences among the scan strategy groups (α = .05). RESULTS: The linear discrepancy values of intraoral scans were not different among scan strategies performed with the single scan and segmental scan methods. In general, differences in the scan motion did not show different accuracies, except for the intermolar distance measured under the scan conditions of a 3-segmental scan and zigzag motion. The global surface deviations were not different among all scan strategies. CONCLUSION: The segmental scan and merge methods using two scan parts appear to be reliable as an alternative to the single scan method for full-arch intraoral scans. When three segmental scans are involved, the accuracy of complete arch scan can be negatively affected.
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Currently, several treatments exist for the improvement of erectile dysfunction (ED). These include medical therapies such as phosphodiesterase type 5 inhibitors (PDE5-Is), invasive methods such as intracavernosal injection therapy of vaso-active substances, vacuum erection devices, and penile prosthesis implants. However, the percentage of patients that are unresponsive to available treatments and who drop out from treatments remains high. Current evidence reveals that the pathogenesis of ED is related to multiple factors including underlying comorbidities, previous surgery, and psychological factors. Diverse approaches using novel molecular pathways or new technologies have been tested as potential therapeutic options for difficultto-treat ED populations. Melanocortin receptor agonist, a centrally acting agent, showed promising results by initiating erection without sexual stimulation in non-responders to PDE5-Is. Recent clinical and pre-clinical studies using human tissues suggested that new peripherally acting agents including the Max-K channel activator, guanylate cyclase activator, and nitric oxide donor could be potential therapies either as a monotherapy or in combination with PDE5-Is in ED patients. According to several clinical trials, regeneration therapy using stem cells showed favorable data in men with diabetic or post-prostatectomy ED. Low-intensity shock wave therapy also demonstrated promising results in patients with vasculogenic ED. There are growing evidences which suggest the efficacy of these emerging therapies, though most of the therapies still need to be validated by well-designed clinical trials. It is expected that, should their long-term safety and efficacy be proven, the emerging treatments can meet the needs of patients hitherto unresponsive to or unsatisfied by current therapies for ED.
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The purpose of this study was to evaluate the bone-generating ability of a new bovine-derived xenograft (S1-XB) containing hydrogel. For control purposes, we used Bio-Oss and Bone-XB bovine-derived xenografts. S1-XB was produced by mixing Bone-XB and hydrogel. Cell proliferation and differentiation studies were performed to assess cytotoxicities and cell responses. For in vivo study, 8 mm-sized cranial defects were formed in 16 rats, and then the bone substitutes were transplanted into defect sites in the four study groups, that is, a Bio-Oss group, a Bone-XB group, an S1-XB group, and a control (all n = 4); in the control group defects were left empty. Eight weeks after surgery, new bone formation areas were measured histomorphometrically. In the cell study, extracts of Bio-Oss, Bone-XB, and S1-XB showed good results in terms of the osteogenic differentiation of human mesenchymal stem cells (hMSCs) and no cytotoxic reaction was evident. No significant difference was observed between mean new bone areas in the Bio-Oss (36.93 ± 4.27%), Bone-XB (35.07 ± 3.23%), and S1-XB (30.80 ± 6.41%) groups, but new bone area was significantly smaller in the control group (18.73 ± 5.59%) (p < 0.05). Bovine-derived bone graft material containing hydrogel (S1-XB) had a better cellular response and an osteogenic effect similar to Bio-Oss.
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This study aimed to compare two methods of crosslinking collagen type I on implanted titanium surfaces, that is, using glutaraldehyde (GA) or gamma-rays (GRs), in a beagle dog model. For in vivo experiments, implants were allocated to three groups and applied to mandibular bone defects in beagle dogs; Group SLA; non-treated Sandblasted, large grit, acid-etched (SLA) implants, Group GA; SLA implants coated with GA crosslinked collagen type I, Group GR; SLA surface implants coated with collagen type I and crosslinked using 25 kGy of 60Co gamma radiation. New bone µCT volumes were obtained, and histologic and histometric analyses were performed in regions of interest. The GR group had significantly better new bone areas (NBAs) and bone to implant contact (BIC) results than the SLA group (p < 0.05), but the GA and GR groups were similar in this respect. New bone volumes and inter-thread bone densities (ITBD) were non-significantly different in the three groups (p > 0.05). Within the limits of this study, gamma-ray collagen crosslinking on titanium implants can be considered a substitute for glutaraldehyde crosslinking.
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The one-pot preparation and structural characterization of silver/poly(p-Cl-phenylsilane) nanocomposites have been performed. The one-step transformation of silver(I) salt to stable silver(0) nanoparticles is mediated by poly(p-Cl-phenylsilane), Cl-PPS having both reactive Si-H bonds in the polymer backbone and C-Cl bonds in the substituents. XRD, TEM, and FE-SEM, and solid-state UV-vis analytical techniques were used to analyze the interesting metal/inorganic polymer hybrid nanocomposites. TEM and FE-SEM data show the formation of hybrid composites in which large number of silver nanoparticles (less than 30 nm of size) are dispersed throughout the Cl-PPS matrix. XRD patterns are consistent with that for fcc-typed silver. The elemental analysis for Cl atom and the polymer solubility confirm that the appreciable cleavage of C-Cl bond and the Si-Cl dative bonding were not occurred. The size and processability of such nanoparticles depend on the ratio of metal to Cl-PPS. In the absence of Cl-PPS, most of the silver particles undergo macroscopic aggregation, which indicates that the polysilane is absolutely necessary for stabilizing the silver nanoparticles.
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This study examined differences of physical activity levels and social interactions among preschoolers with/without disabilities and those at risk for a developmental delay (DD). Sixty preschoolers (20 in each group) were film during their designated large gross motor time. Their physical activity levels and social interaction were examined using the physical activity level screening. Regarding physical activity levels, the result of a two-way analysis of variance indicated significant main effects for groups, F(2,54)=4.192, P=0.02; preschoolers at risk for a DD were more active than preschoolers without disabilities, P=0.02. For social interaction, a significant main effect for groups, F(2,54)=8.994, P<0.001 was found; Preschoolers at risk for a DD were more interactive than preschoolers with/without disabilities, P=0.001 and P=0.002, respectively. There were no significant gender differences across three groups on physical activity levels and social interactions. Although preschoolers at risk for a DD was more active and interactive than the other groups, preschoolers across three groups engaged in light physical activity levels, and had limited social interactions with peers.