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Understanding disordered structure is difficult due to insufficient information in experimental data. Here, we overcome this issue by using a combination of diffraction and simulation to investigate oxygen packing and network topology in glassy (g-) and liquid (l-) MgO-SiO2 based on a comparison with the crystalline topology. We find that packing of oxygen atoms in Mg2SiO4 is larger than that in MgSiO3, and that of the glasses is larger than that of the liquids. Moreover, topological analysis suggests that topological similarity between crystalline (c)- and g-(l-) Mg2SiO4 is the signature of low glass-forming ability (GFA), and high GFA g-(l-) MgSiO3 shows a unique glass topology, which is different from c-MgSiO3. We also find that the lowest unoccupied molecular orbital (LUMO) is a free electron-like state at a void site of magnesium atom arising from decreased oxygen coordination, which is far away from crystalline oxides in which LUMO is occupied by oxygen's 3s orbital state in g- and l-MgO-SiO2, suggesting that electronic structure does not play an important role to determine GFA. We finally concluded the GFA of MgO-SiO2 binary is dominated by the atomic structure in terms of network topology.
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Gestational diabetes mellitus (GDM) is a state of pre-diabetic impaired glucose tolerance initially occurring during pregnancy. Although abnormalities in glucose metabolism normally resolve rapidly after delivery, women with GDM have a higher lifetime risk of developing diabetes mellitus than those without GDM; thus, postpartum healthcare is essential. Of all GDM patients, 5%-10% test positive for diabetes-related autoantibodies, which increase the risk of developing type 1 diabetes mellitus (T1DM). Autoantibody measurement in GDM screening remains debatable; however, it may be useful for the postnatal follow-up of GDM patients at high risk of developing T1DM. We treated a 29-year-old woman who was GDM positive for anti-glutamic acid decarboxylase antibody (GADA) requiring high-dose insulin therapy during pregnancy. As the patient tested positive for GADA, she received judicious postpartum management, allowing for early diagnosis of T1DM and resumption of treatment. Her insulin secretory capacity was preserved at 1 year after parturition, suggesting either slowly progressive insulin-dependent T1DM or latent autoimmune diabetes in adults. This was a rare case of slowly progressive insulin-dependent T1DM or latent autoimmune diabetes in adults in the early postpartum period, but the fact that GADA was positive during pregnancy enabled early treatment without overlooking it. Measuring diabetes-related autoantibodies in patients considered to be at a high risk for T1DM, such as those who are of slim build, young, or suffering from autoimmune thyroid disorders, may be important for appropriate individualized follow-up.
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Diabetes Mellitus Tipo 1 , Diabetes Gestacional , Intolerância à Glucose , Insulinas , Diabetes Autoimune Latente em Adultos , Humanos , Adulto , Gravidez , Feminino , Diabetes Mellitus Tipo 1/complicações , Glutamato Descarboxilase/uso terapêutico , Período Pós-Parto , Autoanticorpos , Insulinas/uso terapêuticoRESUMO
"Welcome to OBGYN World!" A novel recruitment event for medical students organized by the Japan Society of Obstetrics and Gynecology. Since 2012, the number of doctors in Japan who specialize in obstetrics and gynecology has shown a decreasing trend. To increase the number of doctors majoring in obstetrics and gynecology, the Japanese Trainees in Obstetrics and Gynecology subcommittee developed a new recruitment event called Welcome to OBGYN World! (WOW!); the aim of this event was to focus on lower grades of medical students. The present report describes the content of WOW! and the results of a post-event questionnaire administered to participating students and tutors. WOW! was held online in order to avoid the risk of Coronavirus Disease 2019 infection for participants. Sixty of the 82 medical schools nationwide (73.2%) participated in this event. Overall, there were 285 participating students, ranging from first to fourth grade in medical school, and 106 tutors were involved to teach material at the event. In the post-event questionnaire survey, 97.6% (248/254) and 100% of the participants stated they now had a high degree of interest in obstetrics and gynecology and found the specialty attractive, respectively. Furthermore, 93.6% (90/94) of the tutors stated that WOW! had helped recruitment activities in their universities. Based on this outcome, members of the Japanese Trainees of Obstetrics and Gynecology subcommittee will now try to increase the number of doctors specializing in obstetrics and gynecology by holding WOW! annually.
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COVID-19 , Ginecologia , Obstetrícia , Estudantes de Medicina , Feminino , Gravidez , Humanos , Ginecologia/educação , Obstetrícia/educação , JapãoRESUMO
Purpose: Dynamic morphological changes in the chromosome and cytoskeleton occur in mammals and humans during early embryonic development, and abnormalities such as embryonic chromosomal aneuploidy occur when development does not proceed normally. Visualization of the intracellular organelles and cytoskeleton allows elucidation of the development of early mammalian embryos. The behavior of the DNA and cytoskeleton in early mammalian embryos has conventionally been observed by injecting target molecule mRNAs, incorporating a fluorescent substance-expressing gene, into embryos. In this study, we visualized the chronological behavior of male and female chromosome condensation in mouse embryos, beginning in the two-pronuclear zygote, through the first division to the two-cell stage, using fluorescent chemical probes to visualize the behavior of DNA, microtubules, and microfilaments. Method: Mouse two-pronuclear stage embryo were immersed in medium containing fluorescent chemical probes to visualize DNA, microtubules, and microfilaments. Observation was performed with a confocal microscope. Results: This method allowed us to observe how chromosome segregation errors in first somatic cell divisions in mouse embryos and enabled dynamic analysis of a phenomenon called lagging chromosomes. Conclusions: By applying this method, we can observe any stage of embryonic development, which may provide new insights into embryonic development in other mammals.
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AIM: Obstetrics and gynecology (Ob/Gyn) training became compulsory for Japanese physician interns from April 2020 to improve medical competence in treating women's diseases. This study aims to understand the Ob/Gyn training needs of postgraduate year 1-2 physicians (interns) and thereby improve training efficiency. METHODS: This study was administered to interns at Ob/Gyn training facilities from December 2019 to February 2020. An original questionnaire was used to evaluate their assessment of training needs. In analyses, interns were categorized according to whether they were willing to major in Ob/Gyn. RESULTS: Of the 1154 participants, 163 (14.1%) would major in Ob/Gyn (Ob/Gyn applicants) and 967 (83.8%) would not (non-Ob/Gyn applicants). At the time of the survey, 634 (54.9%) had rotated in Ob/Gyn, 253 (21.9%) planned to rotate, and 267 (23.1%) chose not to rotate. The two most favorable training experiences were "experience in surgical procedures" (81/141, 57.4%) and "wide treatment areas covered by Ob/Gyn" (78/141, 55.3%) among the Ob/Gyn applicants, and "specificity of women's treatment" (308/488, 63.1%) among the non-Ob/Gyn applicants. CONCLUSIONS: Ob/Gyn applicants and non-Ob/Gyn applicants differed in their assessment of Ob/Gyn rotations. It is crucial to provide medical training based on interns' needs to improve their skills for treating female patients.
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Ginecologia , Internato e Residência , Obstetrícia , Currículo , Feminino , Ginecologia/educação , Humanos , Japão , Obstetrícia/educação , Gravidez , Inquéritos e QuestionáriosRESUMO
BACKGROUNDS: In 2013, the total number of obstetrician-gynecologists decreased. The Japanese Society of Obstetrics and Gynecology established the Obstetrics and Gynecology MIRAI Committee in 2015. Within the MIRAI Committee, Japanese Trainees in Obstetrics and Gynecology (JTOG) was established; it was comprised of 20 promising young obstetrician-gynecologists recommended from regions across Japan. The office term is 2 years. OBJECTIVE: The purpose of this report is to learn and inform about the results of MIRAI's activities. METHODS: We surveyed the trends in new obstetrician-gynecologists and also matched each seminar participant with them. RESULT: The number of new memberships has been increasing since the nadir in 2016. In particular, there are over 100 more new physicians specializing in the field in 2020 than there were at the nadir in 2016. It was revealed that approximately 50% of the participants in the summer school specialized in obstetrics and gynecology. Furthermore, approximately 70% of POP2 participants specialized in obstetrics and gynecology, which shows that these two recruitment seminars are extraordinarily effective events that result in an increase in the number of new obstetricians and gynecologists. CONCLUSION: We conclude that the activities of this MIRAI Committee and JTOG have been effective. With the spread of COVID-19 and the inability of obstetrician-gynecologists and students/clinical trainees to perform social distancing, it is currently difficult to hold hands-on seminars. However, we hope that new JTOG members will be able to create a new seminar format.
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COVID-19 , Ginecologia , Obstetrícia , Humanos , Japão , SARS-CoV-2RESUMO
AIM: The Ministry of Health, Labour, and Welfare of Japan proposed a regulation of overtime work as a reform in work style. However, the regulation may deteriorate the quality of medical services due to the reduction in training time. Thus, the study aimed to reveal perceptions in terms of generation gaps in views on self-training and overtime work, among members of the Japan Society of Obstetrics and Gynecology (JSOG). METHODS: A web-based, self-administered questionnaire survey was conducted among members of the JSOG. In total, 1256 respondents were included in the analysis. Data were collected on age, sex, experience as a medical doctor, location of workplace, work style, the type of main workplace, and number of full-time doctors in the main workplace. The study examined the attitudes of the respondents toward overtime work and self-training. The respondents were categorized based on experience as a medical doctor. RESULTS: According to years of experience, 112 (8.9%), 226 (18.0%), 383 (30.5%), 535 (42.6%) doctors have been working for ≤5, 6-10, 11-19, and ≥ 20 years, respectively. Although 54.5% of doctors with ≤5 years of experience expected the regulation on working hours to improve the quality of medical services, those with ≥20 years of experience expressed potential deterioration. After adjusting for covariates, more years of experience were significantly related with the expectation of deterioration in the quality of medical services. CONCLUSIONS: The study revealed a generation gap in the views about self-training and overtime work among obstetricians and gynecologists in Japan.
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Ginecologia , Obstetrícia , Atitude , Humanos , Japão , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: The aim of this study was to investigate neutrophil elastase (NE) in amniotic fluid as a potential marker for predicting pregnancy continuation. MATERIAL AND METHODS: We enrolled 34 pregnant women with bulging fetal membrane during the second trimester who underwent emergent cerclage after confirming the absence of intrauterine infection (amniotic fluid glucose ≥15 mg/dL). Amniotic fluid NE levels were compared between women who completed and did not complete 30, 34, and 36 weeks of gestation, and the optimal cut-off value for predicting pregnancy continuation was estimated. Moreover, the differences in the duration of continued pregnancy were compared between women with NE levels above and below the optimal cut-off value. RESULTS: The optimal cut-off value for NE in amniotic fluid that predicted pregnancy continuation beyond 30, 34, and 36 weeks of gestation was 180 ng/mL; this cut-off value had a sensitivity, specificity, positive predictive value, and negative predictive value of 84.0, 77.8, 91.3, and 63.7% beyond 30 weeks of gestation; 87.5, 80.0, 91.5, and 72.3% beyond 34 weeks of gestation; and 85.0, 71.4, 80.9, and 76.9% beyond 36 weeks of gestation, respectively. The duration of continued pregnancy from emergent cerclage to delivery was significantly longer in women with amniotic fluid NE <180 ng/mL (95.1 ± 5.4 days) than in women with amniotic fluid NE ≥180 ng/mL (44.8 ± 14.3 days). CONCLUSION: The NE levels in amniotic fluid may serve as a useful marker for predicting the duration of continued pregnancy after cervical cerclage.
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Líquido Amniótico/metabolismo , Cerclagem Cervical/estatística & dados numéricos , Elastase de Leucócito/análise , Trabalho de Parto Prematuro/metabolismo , Segundo Trimestre da Gravidez/metabolismo , Incompetência do Colo do Útero/sangue , Amniocentese , Feminino , Humanos , Trabalho de Parto Prematuro/etiologia , Gravidez , Resultado da GravidezRESUMO
Pressure induced amorphization provides a distinct route to prepare novel amorphous materials. Single crystals of the porous aluminophosphate AlPO4-17 directly transform to an amorphous state beginning at 0.6 GPa, without fragmentation into polycrystalline material. Apart from a reduction in dimensions, the amorphous material retains the form of the initial single crystal. Remnant crystalline domains in the amorphous material also preserve the initial orientation of the single crystal. X-ray diffraction indicates the compression of the structure around the empty pores in the xy plane and such an amorphization mechanism is consistent with a direct structural relationship between the single crystal and amorphous forms. The collapse of the initial pore volume is almost complete at 2.5 GPa. A memory effect is observed in the amorphous form, which strongly expands on decompression. The present process opens the way for the synthesis of topologically ordered amorphous materials approaching "perfect glasses" with improved mechanical properties.
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Thermodynamically metastable glasses that can contain metastable species are important functional materials. X-ray absorption near-edge structure (XANES) spectroscopy is an effective technique for determining the valence states of cations, especially for the doping element in phosphors. Herein, we first confirm the valence change of silver cations from monovalent to trivalent in aluminophosphate glasses by X-ray irradiation using a combination of Ag L3-edge XANES, electron spin resonance, and simulated XANES spectra based on first-principles calculations. The absorption edge of the experimental and simulated XANES spectra demonstrate the spectral features of Ag(III), confirming that AgO exists as Ag(I)Ag(III)O2. A part of Ag(I) changes to Ag(III) by X-ray irradiation, and the generation of Ag(III) is saturated after high irradiation doses, in good agreement with conventional radiophotoluminescence (RPL) behaviour. The structural modelling based on a combination of quantum beam analysis suggests that the local coordination of Ag cations is similar to that of Ag(III), which is confirmed by density functional theory calculations. This demonstration of Ag(III) in glass overturns the conventional understanding of the RPL mechanism of silver cations, redefining the science of silver-related materials.
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The topology of amorphous materials can be affected by mechanical forces during compression or milling, which can induce material densification. Here, we show that densified amorphous silica (SiO2) fabricated by cold compression of siliceous zeolite (SZ) is permanently densified, unlike densified glassy SiO2 (GS) fabricated by cold compression although the X-ray diffraction data and density of the former are identical to those of the latter. Moreover, the topology of the densified amorphous SiO2 fabricated from SZ retains that of crystalline SZ, whereas the densified GS relaxes to pristine GS after thermal annealing. These results indicate that it is possible to design new functional amorphous materials by tuning the topology of the initial zeolitic crystalline phases.
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The fabrication of novel oxide glass is a challenging topic in glass science. Alumina (Al2O3) glass cannot be fabricated by a conventional melt-quenching method, since Al2O3 is not a glass former. We found that amorphous Al2O3 synthesized by the electrochemical anodization of aluminum metal shows a glass transition. The neutron diffraction pattern of the glass exhibits an extremely sharp diffraction peak owing to the significantly dense packing of oxygen atoms. Structural modeling based on X-ray/neutron diffraction and NMR data suggests that the average Al-O coordination number is 4.66 and confirms the formation of OAl3 triclusters associated with the large contribution of edge-sharing Al-O polyhedra. The formation of edge-sharing AlO5 and AlO6 polyhedra is completely outside of the corner-sharing tetrahedra motif in Zachariasen's conventional glass formation concept. We show that the electrochemical anodization method leads to a new path for fabricating novel single-component oxide glasses.
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Introduction: In recent years, there has been an increase in noninvasive prenatal testing (NIPT), where maternal blood samples are used to extract fetal cell-free DNA. Despite this being offered in several facilities in urban areas, NIPT remains to be scarcely unavailable in rural areas. Moreover, there is lacking information with regard to how pregnant women in rural areas perceive NIPT. Thus, in this study, we conducted a survey among pregnant women who came to our clinic for NIPT and examined their views on NIPT and genetic counseling. Methods: A questionnaire survey was administered to pregnant women who requested NIPT and underwent genetic counseling at our hospital between November 2016 and February 2020. The questionnaire was administered twice, once after completing the genetic counseling and once after explaining the NIPT results. The number of genetic counseling and NIPT sessions and positive test results, as well as anxiety about the test and evaluation of genetic counseling and NIPT, were assessed. Results: In total, 115 patients received genetic counseling, of which 109 underwent NIPT. The test results were found to be positive in six patients. As per our findings, 103 patients (93%) indicated they needed genetic counseling for NIPT, whereas 99 (93%) were satisfied with the counseling they received from a genetic medicine specialist. On the other hand, 82 patients (77%) requested for more testing facilities. Conclusions: The enhancement of genetic counseling systems is essential to expand the environment in which NIPT is performed. Therefore, we need to consider the need to make the NIPT testing environment more conducive and inform clients of the importance of genetic counseling in NIPT.
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Objectives: To investigate the association between online activities and the number of new obstetrics and gynecology senior residents. Methods: A nationwide web-based, self-administered anonymous survey was conducted to investigate recruitment and clerkship activities during the coronavirus disease 2019 pandemic. An online questionnaire was sent to 576 obstetrics and gynecology training institutions in Japan between December 21, 2020, and January 31, 2021. Overall, 334 institutions that gave valid responses were included (response rate: 58.0%). Multivariate logistic regression analysis examined the association between online activities, including recruitment and clerkship activities, and the number of new obstetrics and gynecology senior residents in 2021. The stratified analysis by implementing face-to-face activities was conducted to clarify the association. Results: The number of new senior residents increased in 187 facilities (56.0%) and decreased in 147 facilities (44.0%). The facilities that implemented face-to-face and online activities were 185 (55.4%) and 120 (35.9%), respectively. In multivariate logistic regression analysis, an increased number of new obstetrics and gynecology senior residents was significantly associated with face-to-face activities (adjusted odds ratio (AOR)=2.58, 95% confidence interval (CI): 1.11-5.97, p<.001) but not with online activities. In the stratified analysis, online activities were significantly associated with an increased number of new obstetrics and gynecology senior residents among the facilities without face-to-face activities (AOR=3.81, 95% CI: 1.40-10.32, p=.009) but not among those with face-to-face activities (AOR=0.87, 95% CI: 0.42-1.78). Conclusions: Online activities were associated with an increased number of new obstetrics and gynecology senior residents among the facilities that did not conduct face-to-face activities.
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COVID-19 , Ginecologia , Internato e Residência , Obstetrícia , COVID-19/epidemiologia , Feminino , Ginecologia/educação , Humanos , Obstetrícia/educação , Gravidez , Inquéritos e QuestionáriosRESUMO
The structure of disordered materials is still not well understood because of insufficient experimental data. Indeed, diffraction patterns from disordered materials are very broad and can be described only in pairwise correlations because of the absence of translational symmetry. Brilliant hard x-rays from third-generation synchrotron radiation sources enable us to obtain high-quality diffraction data for disordered materials from ambient to high temperature and high pressure, which has significantly improved our grasp of the nature of order in disordered materials. Here, we introduce the progress in the instrumentation for hard x-ray beamlines at SPring-8 over the last 20 years with associated results and advanced data analysis techniques to understand the topology in disordered materials.
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The network topology in disordered materials is an important structural descriptor for understanding the nature of disorder that is usually hidden in pairwise correlations. Here, we compare the covalent network topology of liquid and solidified silicon (Si) with that of silica (SiO2) on the basis of the analyses of the ring size and cavity distributions and tetrahedral order. We discover that the ring size distributions in amorphous (a)-Si are narrower and the cavity volume ratio is smaller than those in a-SiO2, which is a signature of poor amorphous-forming ability in a-Si. Moreover, a significant difference is found between the liquid topology of Si and that of SiO2. These topological features, which are reflected in diffraction patterns, explain why silica is an amorphous former, whereas it is impossible to prepare bulk a-Si. We conclude that the tetrahedral corner-sharing network of AX2, in which A is a fourfold cation and X is a twofold anion, as indicated by the first sharp diffraction peak, is an important motif for the amorphous-forming ability that can rule out a-Si as an amorphous former. This concept is consistent with the fact that an elemental material cannot form a bulk amorphous phase using melt quenching technique.
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This prospective study evaluated the accuracy of non-invasive preimplantation genetic testing for aneuploidy (niPGT-A) using cell-free DNA in spent culture medium, as well as that of preimplantation genetic testing for aneuploidy (PGT-A) using trophectoderm (TE) biopsy after culturing beyond implantation. Twenty frozen blastocysts donated by 12 patients who underwent IVF at our institution were investigated. Of these, 10 were frozen on day 5 and 10 on day 6. Spent culture medium and TE cells were collected from each blastocyst after thawing, and the embryos were cultured in vitro for up to 10 days. The outgrowths after culturing beyond implantation were sampled and subjected to chromosome analysis using next-generation sequencing. Chromosomal concordance rate, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), false-positive rate (FPR), and false-negative rate (FNR) of niPGT-A and PGT-A against each outgrowth were analyzed. The concordance rate between the niPGT-A and outgrowth samples was 9/16 (56.3%), and the concordance rate between the PGT-A and outgrowth samples was 7/16 (43.8%). NiPGT-A exhibited 100% sensitivity, 87.5% specificity, 88.9% PPV, 100% NPV, 12.5% FPR, and 0% FNR. PGT-A exhibited 87.5% sensitivity, 77.8% specificity, 87.5% PPV, 75% NPV, 14.3% FPR, and 22.2% FNR. NiPGT-A may be more accurate than PGT-A in terms of ploidy diagnostic accuracy in outgrowths.
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Aneuploidia , Ácidos Nucleicos Livres/genética , Biópsia , Blastocisto/metabolismo , Blastocisto/patologia , Meios de Cultura/análise , Técnicas de Cultura Embrionária , Implantação do Embrião , Fertilização in vitro , Testes Genéticos , Humanos , Projetos Piloto , Diagnóstico Pré-ImplantaçãoRESUMO
La2O3-Ga2O3 binary glass exhibits unusual optical properties owing to its high oxygen polarizability and low vibration energy. These optical properties include high refractive indices and a wide transmittance range. In this study, we performed classical molecular dynamics simulations on La2O3-Ga2O3 glass synthesized by an aerodynamic levitation technique. We have obtained structural models that reproduce experimental results, such as NMR, high-energy X-ray diffraction, and neutron diffraction. Based on our analysis, the structural features were clarified: 5-, 6-coordinated Ga, edge-sharing GaOx-GaOx polyhedral linkages, and oxygen triclusters. Additionally, the vibrational density of states was calculated by diagonalization of the dynamical matrix derived from the structural models and the results were compared with Raman scattering spectra. The mode analysis of the Raman spectra revealed that the principal bands at 650 cm-1 were mainly attributed to the stretching modes of the bridging and nonbridging oxygens. Meanwhile, the shoulder bands at the highest frequency of 750 cm-1 were mainly attributed to the stretching modes of the bridging oxygens and oxygen triclusters. The structural models obtained in this study well describe the characteristic local structures and vibrational properties of the La2O3-Ga2O3 glass.
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Understanding the structure-property relationship of glass material is still challenging due to a lack of periodicity in disordered materials. Here, we report the properties and atomic structure of vanadium phosphate glasses characterized by reverse Monte Carlo modelling based on neutron/synchrotron X-ray diffraction and EXAFS data, supplemented by Raman and NMR spectroscopy. In vanadium-rich glass, the water durability, thermal stability and hardness improve as the amount of P2O5 increases, and the network former of the glass changes from VOx polyhedra to the interplay between VOx polyhedra and PO4 tetrahedra. We find for the first time that the coordination number of oxygen atoms around a V4+ is four, which is an unusually small coordination number, and plays an important role for water durability, thermal stability and hardness. Furthermore, we show that the similarity between glass and crystal beyond the nearest neighbour distance is important for glass properties. These results demonstrate that controlling the oxygen coordination and valence of the network-forming cation is necessary for designing the properties of glass.
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Understanding glass structure is still challenging due to the result of disorder, although novel materials design on the basis of atomistic structure has been strongly demanded. Here we report on the atomic structures of the zinc phosphate glass determined by reverse Monte Carlo modelling based on diffraction and spectroscopic data. The zinc-rich glass exhibits the network formed by ZnOx (averaged x<4) polyhedra. Although the elastic modulus, refractive index and glass transition temperature of the zinc phosphate glass monotonically increase with the amount of ZnO, we find for the first time that the thermal expansion coefficient is very sensitive to the substitution of the phosphate chain network by a network consisting of Zn-O units in zinc-rich glass. Our results imply that the control of the structure of intermediate groups may enable new functionalities in the design of oxide glass materials.