Effects of sleep quality in early pregnancy on pregnancy outcomes and mood state.

PURPOSE: To clarify the relationship between quality of sleep and pregnancy outcomes and to explore how sleep quality affects mood state in the first trimester of pregnancy. METHODS: This prospective cohort study enrolled pregnant women from June 2020 to June 2021. Maternal sleep conditions, daytime sleepiness, and mood state in the first trimester were assessed using four Chinese self-rating scales, namely, the Pittsburgh Sleep Quality Index (PSQI), the Sleep Hygiene Practice Scale (SHPS), Epworth Sleepiness Scale (ESS), and the abbreviated version of the Profile of Mood States (a-POMS). Participants were divided into an exposed group (PSQI score > 5, poor sleep quality group) and a non-exposed group (PSQI score ≤ 5, good sleep quality group). Maternal characteristics, pregnancy outcomes, and the relationship among sleep quality, sleepiness, and mood state were analyzed. Comparisons of sleep hygiene behavior variables between the two subgroups were also analyzed. RESULTS: A total of 2703 pregnant women were enrolled in the study. Poor sleep quality increased the probability of gestational diabetes mellitus (GDM) (1.573, 1.315-1.863), liver function damage (1.467, 1.021-2.107), preterm delivery (1.468, 1.077-2.002), mild sleepiness (1.612, 1.357-1.915), and excessive sleepiness (2.134, 1.686-2.701). Poor maternal sleep quality was significantly associated with the occurrence of preterm premature rupture of membranes (1.947, 1.168-3.243) and perinatal death (1.003, 1.000-1.006). Additionally, a significant positive correlation between the PSQI score and the total mood disturbance (TMD) score was revealed by Spearman's correlation analysis (r = 0.378, P < 0.01). Enter Regression analysis demonstrated that sleep quality (R2 = 0.390, P < 0.01) and sleepiness (R2 = 0.234, P < 0.01) exerted significant direct effects on mood state during pregnancy. Furthermore, Spearman's correlation analysis indicated a positive association between the PSQI score and the SHPS total score (r = 0.227, P < 0.01). CONCLUSIONS: Poor sleep quality is significantly associated with elevated rates of maternal mood disturbances, obstetric complications, and adverse outcomes in infants. The findings suggest that it may be useful to provide comprehensive sleep assessment and education on sleep hygiene during the early stages of pregnancy.

Understanding Chromium Slag Recycling with Sintering-Ironmaking Processes: Influence of Cr2O3 on the Sinter Microstructure and Mechanical Properties of the Silico-Ferrite of Calcium and Aluminum (SFCA).

Chromium slag is a solid waste of chromium salt production, which contains highly toxic Cr(VI) and significant amounts of valuable metals, such as Fe and Cr. Recycling chromium slag as a raw sintering material in sintering-ironmaking processes can simultaneously reduce toxic Cr(VI) and recover valuable metals. A micro-sintering experiment, compressive strength test, microhardness test, and first-principles calculation are performed to investigate the influence of Cr2O3 on the sintering microstructure and mechanical properties of the silico-ferrite of calcium and aluminum (SFCA) in order to understand the basis of the sintering process with chromium slag addition. The results show that the microstructure of SFCA changes from blocky to interwoven, with further increasing Cr2O3 content from 0 wt% to 3 wt%, and transforms to blocky with Cr2O3 content increasing to 5 wt%. Cr2O3 reacts with Fe2O3 to form (Fe1-xCrx)2O3 (0 ≤ x ≤ 1), which participates in forming SFCA. With the increase in Cr doping concentrations, the hardness of SFCA first decreases and then increases, and the toughness increases. When Cr2O3 content increases from 0 wt% to 3 wt%, the SFCA microhardness decreases and the compressive strength of the sintered sample increases. Further increasing Cr2O3 contents to 5 wt%, the SFCA microhardness increases, and the compressive strength of sintered sample decreases.

Coordination-Controlled Catalytic Activity of Cobalt Oxides for Ozone Decomposition.

Nowadays, it is still elusive and challenging to discover the active sites of cobalt (Co) cations in different coordination structures, though Co-based oxides show their great potency in catalytic ozone elimination for air cleaning. Herein, different Co-based oxides are controllably synthesized including hexagonal wurtzite CoO-W with Co2+ in tetrahedral coordination (CoTd2+) and CoAl spinel with dominant CoTd2+, cubic rock salt CoO-R with Co2+ in octahedral coordination (CoOh2+), MgCo spinel with dominant Co3+ in octahedral coordination (CoOh3+), and Co3O4 with mixed CoTd2+ and CoOh3+. The valences are proved by X-ray photoelectron spectroscopy, and the coordinations are verified by X-ray absorption fine structure analysis. The ozone decomposition performances are CoOh3+ ∼ CoOh2+ ≫ CoTd2+, and CoOh3+ and CoOh2+ show a lower apparent activation energy of ∼42-44 kJ/mol than CoTd2+ (∼55 kJ/mol). In specific, MgCo shows the highest decomposition efficiency of 95% toward 100 ppm ozone at a high space velocity of 1,200,000 mL/gh, which still retains at 80% after a long-term running of 36 h at room temperature. The high activity is explained by the d-orbital splitting in the octahedral coordination, favoring the electron transfer in ozone decomposition reactions, which is also verified by the simulation. These results show the promising prospect of the coordination tuning of Co-based oxides for highly active ozone decomposition catalysts.

Application of a translational profiling approach for the comparative analysis of CNS cell types.

Comparative analysis can provide important insights into complex biological systems. As demonstrated in the accompanying paper, translating ribosome affinity purification (TRAP) permits comprehensive studies of translated mRNAs in genetically defined cell populations after physiological perturbations. To establish the generality of this approach, we present translational profiles for 24 CNS cell populations and identify known cell-specific and enriched transcripts for each population. We report thousands of cell-specific mRNAs that were not detected in whole-tissue microarray studies and provide examples that demonstrate the benefits deriving from comparative analysis. To provide a foundation for further biological and in silico studies, we provide a resource of 16 transgenic mouse lines, their corresponding anatomic characterization, and translational profiles for cell types from a variety of central nervous system structures. This resource will enable a wide spectrum of molecular and mechanistic studies of both well-known and previously uncharacterized neural cell populations.

The incidence, indications, risk factors and pregnancy outcomes of peripartum hysterectomy at a tertiary hospital between 2013 and 2022.

OBJECTIVE: To analyze the incidence, indications, risk factors and pregnancy outcomes of postpartum hemorrhage resulting in peripartum hysterectomy (PH). METHODS: We retrospectively reviewed patients with postpartum hemorrhage requiring surgical procedures at ≥ 28 weeks of gestation from January 1, 2013 to December 31, 2022 at a tertiary hospital in Shanghai, China. The patients were divided into a PH group and a non-PH group. Maternal clinical characteristics, the management of postpartum hemorrhage, pregnancy outcomes were compared between groups. Logistic regression was used to analyze the correlations between risk factors and PH. RESULTS: The incidence of hysterectomy was 0.2/1000 deliveries (31/150194). The variables significantly associated with PH were placenta previa with placenta increta/percreta (OR36.26), uterine rupture (OR266.16) and an estimated blood loss ≥ 3513 mL (OR431.11). The proportion of cases involving hemorrhagic shock, disseminated intravascular coagulation, bladder injury, neonatal severe asphyxia, neonatal death and hypoxic-ischemic encephalopathy were significantly higher in the PH group (P < 0.05). CONCLUSION: The most common indications of PH were placental pathology. Efforts should be made to reduce the rate of cesarean deliveries and uterine curettage to lower the probability of abnormal placental invasion and appropriate medical indications for trial of labor after cesarean should be strictly followed to avoid the risk of uterine rupture.

Heterojunctioned CuO/Cu2O catalyst for highly efficient ozone removal.

In recent years, near surface ozone pollution, has attracted more and more attention, which necessitates the development of high efficient and low cost catalysts. In this work, CuO/Cu2O heterojunctioned catalyst is fabricated by heating Cu2O at high temperature, and is adopted as ozone decomposition catalyst. The results show that after Cu2O is heated at 180°C conversion of ozone increases from 75.2% to 89.3% at mass space velocity 1,920,000 cm3/(g·hr) in dry air with 1000 ppmV ozone, which indicates that this heterojunction catalyst is one of the most efficient catalysts reported at present. Catalysts are characterized by electron paramagnetic resonance spectroscopy and ultraviolet photoelectron spectroscopy, which confirmed that the heterojunction promotes the electron transfer in the catalytic process and creates more defects and oxygen vacancies in the CuO/Cu2O interfaces. This procedure of manufacturing heterostructures would also be applicable to other metal oxide catalysts, and it is expected to be more widely applied to the synthesis of high-efficiency heterostructured catalysts in the future.

Highly efficient ozone elimination by metal doped ultra-fine Cu2O nanoparticles.

Nowadays, ozone contamination becomes dominant in air and thus challenges the research and development of cost-effective catalyst. In this study, metal doped Cu2O catalysts are synthesized via reduction of Cu2+ by ascorbic acid in base solutions containing doping metal ions. The results show that compared with pure Cu2O, the Mg2+ and Fe2+ dopants enhance the O3 removal efficiency while Ni2+ depresses the activity. In specific, Mg-Cu2O shows high O3 removal efficiency of 88.4% in harsh environment of 600,000 mL/(g·hr) space velocity and 1500 ppmV O3, which is one of the highest in the literature. Photoluminescence and electron paramagnetic spectroscopy characterization shows higher concentration of crystal defects induced by the Mg2+ dopants, favoring the O3 degradation. The in-situ diffuse reflectance Fourier transform infrared spectroscopy shows the intermediate species in the O3 degradation process change from O22- dominant of pure Cu2O to O2- dominant of Mg-Cu2O, which would contribute to the high activity. All these results show the promising prospect of the Mg-Cu2O for highly efficiency O3 removal.

Ceramic tiles with black pigment made from stainless steel plant dust: Physical properties and long-term leaching behavior of heavy metals.

UNLABELLED: Stainless steel plant dust is a hazardous by-product of the stainless steelmaking industry. It contains large amounts of Fe, Cr, and Ni, and can be potentially recycled as a raw material of inorganic black pigment in the ceramic industry to reduce environmental contamination and produce value-added products. In this paper, ceramic tiles prepared with black pigment through recycling of stainless steel plant dust were characterized in terms of physical properties, such as bulk density, water absorption, apparent porosity, and volume shrinkage ratio, as well as the long-term leaching behavior of heavy metals (Cr, Ni, Pb, Cd, and Zn). The results show that good physical properties of ceramic tiles can be obtained with 8% pigments addition, sample preparation pressure of 25 MPa, and sintering at 1200 ºC for 30 min. The major controlling leaching mechanism for Cr and Pb from the ceramic tiles is initial surface wash-off, while the leaching behavior of Cd, Ni, and Zn from the stabilized product is mainly controlled by matrix diffusion. The reutilization process is safe and effective to immobilize the heavy metals in the stainless steel plant dust. IMPLICATIONS: Stainless steel plant dust is considered as a hazardous material, and it can be potentially recycled for black pigment preparation in the ceramic industry. This paper provides the characteristics of the ceramic tiles with black pigment through recycling stainless steel plant dust, and the long-term leaching behavior and controlling leaching mechanisms of heavy metals from the ceramic tile. The effectiveness of the treatment process is also evaluated.

Effect of blast orientation, multi-point blasts, and repetitive blasts on brain injury.

Explosions in the battlefield can result in brain damage. Research on the effects of shock waves on brain tissue mainly focuses on the effects of single-orientation blast waves, while there have been few studies on the dynamic response of the human brain to directional explosions in different planes, multi-point explosions and repetitive explosions. Therefore, the brain tissue response and the intracranial pressure (ICP) caused by different blast loadings were numerically simulated using the CONWEP method. In the study of the blast in different directions, the lateral explosion blast wave was found to cause greater ICP than did blasts from other directions. When multi-point explosions occurred in the sagittal plane simultaneously, the ICP in the temporal lobe increased by 37.8 % and the ICP in the parietal lobe decreased by 17.6 %. When multi-point explosions occurred in the horizontal plane, the ICP in the frontal lobe increased by 61.8 % and the ICP in the temporal lobe increased by 12.2 %. In a study of repetitive explosions, the maximum ICP of the second blast increased by 40.6 % over that of the first blast, and that of the third blast increased by 61.2 % over that of the second blast. The ICP on the brain tissue from repetitive blasts can exceed 200 % of that of a single explosion blast wave.

Enhancing peach slices radio frequency vacuum drying by combining ultrasound and ultra-high pressure as pretreatments: Effect on drying characteristics, physicochemical quality, texture and sensory evaluation.

To maximally maintain fruits and vegetables quality after harvest, this study used ultrasonic (US) and ultra-high pressure (UHP) techniques as pretreatments for radio frequency vacuum (RFV) drying of peach slices, and investigated the effects of different pretreatments (US, UHP, UHP-US, and US-UHP) on drying characteristics, physicochemical qualities, texture properties, and sensory evaluation of peach slices. Results showed that the drying rate was increased by 15.79 âˆ¼ 54.39 % and the contents of pectin, hemicellulose, total phenolic, total flavonoid, phenolic acids, individual sugar annd antioxidant of the samples were significantly increased after US combined with UHP pretreatment (P < 0.05). US-UHP + RFV dried peach slices obtained brighter color, better texture attributes of hardness, cohesiveness, chewiness, springiness, and resilience. The dehydrated samples pretreated by UHP-US had the best overall acceptance, appearance, and crispness with lower off-odor and sourness compared to the dehydrated peach slices with US and UHP pretreatment. Notably, the highest cellulose and organic acids were found in dehydrated peach slices by control, followed by samples US, and samples with UHP pretreatment. The microstructure showed that the internal organization of peach slices appeared as uniform and regular honeycomb porous structure after US-UHP pretreatment. The findings may provide theoretical reference for the development of energy-efficient and high-quality drying technology for fruits and vegetables.

Effects of Different Drying Methods on the Drying Characteristics and Quality of Codonopsis pilosulae Slices.

The present study aimed to investigate the effect of rotary microwave vacuum drying (RMVD), radio frequency vacuum drying (RFVD), vacuum far infrared drying (VFID), vacuum drying (VD), hot air drying (HD) and natural drying (ND) on the drying characteristics, active ingredients and microstructure of Codonopsis pilosulae slices. Compared with the fitting results of the four models, the Weibull model is the most suitable drying model for Codonopsis. The RFVD and HD color difference values were smaller compared to ND. The effective moisture diffusivity (Deff) under different drying methods was between 0.06 × 10-8 m2/s and 3.95 × 10-8 m2/s. RMVD-dried products had the shortest drying time and retained more active ingredients. The microstructure analysis revealed that the porous structure of RMVD is more favorable for water migration. RMVD is a promising dehydration method for obtaining high-value-added dried Codonopsis products.

Effect of an Ultrasound Pre-Treatment on the Characteristics and Quality of Far-Infrared Vacuum Drying with Cistanche Slices.

In this study, the effect of an ultrasound (US) pre-treatment on the process of drying Cistanche slices through far-infrared vacuum drying was investigated with various experimental factors, including the US treatment time (25, 35, 45 min), frequency (20, 40, 60 kHz) and power (150, 180, 210 W). The results showed that compared with the samples without US, the material drying time after the US treatment was reduced by 16-36.8%. The effective moisture diffusion coefficients of Cistanche slices under different US conditions ranged from 1.61122 × 10-8 to 2.39274 × 10-8 m2/s, which agreed with food processing ranges. In addition, the phenylethanoid glycoside, iridoid, polysaccharide, total phenol and total flavonoid contents in Cistanche were significantly increased after US pre-treatment. However, the dried products obtained with the 45 min US treatment had greatly damaged internal structures, collapsed and seriously deformed surfaces, and low contents of active ingredients. Overall, the US pre-treatment could significantly improve the drying quality of Cistanche slices.

Combined measurement of circulating tumor cell counts and serum tumor marker levels enhances the screening efficiency for malignant versus benign pulmonary nodules.

BACKGROUND: The high false-positive rate for pulmonary nodules (PNs) from using low-dose computed tomography (LDCT) screening can lead to overuse of invasive procedures, overtreatment, and patient anxiety. Therefore, it is very important to develop new diagnostic methods. METHODS: A negative enrichment-fluorescence in situ hybridization (NE-FISH) approach was used to detect circulating tumor cells (CTCs) in patients with PNs. We evaluated whether or not the combination of CTC counts with serum tumor marker levels (CEA, CA 125, CYFRA 21-1, SCC) could improve the diagnostic ability for distinguishing patients with malignant pulmonary nodules (MPNs) from those with benign pulmonary nodules (BPNs). Moreover, the potential clinical application of this combination for the diagnosis of solitary pulmonary nodules (SPNs) with a diameter ≤2 cm was also investigated. RESULTS: The combination of CTC counts and tumor marker levels had a sensitivity of 80.12% and the area under the receiver operating characteristics curve (AUCROC ) of 0.853 (95% confidence interval [CI]: 0.800-0.897, p < 0.001) for the differential diagnosis of PNs. For early cancer stages, the sensitivity was 75.38% (AUCROC  = 0.780, 95% CI: 0.713-0.838, p < 0.001). In addition, for SPNs within 2 cm the combination of CTC counts and tumor marker levels was still the most valuable diagnostic tool with a sensitivity of 78.95% and AUCROC of 0.888. CONCLUSION: The combination of CTC counts and serum tumor marker levels is helpful for improving the diagnosis of PNs, especially in the early stages of cancer and for SPNs within 2 cm.

Characteristics and chemical speciation of waste copper slag.

Waste copper slag contains abundant valuable metal element Fe, and residual elements such as Cu, As, Pb, Zn, and Mo. Simply stockpiling or landfilling would waste valuable metal resources and cause contamination due to the leachable harmful elements. In this paper, the HJ/T299-2007 test and TCLP test have been utilized to evaluate the leaching toxicity of waste copper slag, while the sequential extraction procedure was carried out to investigate the different chemical speciation and the bioavailability of the residual metal elements in the waste copper slag. The results show that Pb in the waste copper slag exceeds the regulatory value of TCLP in the leaching tests, which means that the waste copper slag may contaminate the surrounding environment. According to the characteristics of the waste copper slag, the residual metal elements are mainly wrapped by the fayalite or silicate matrix. Cu and Fe are mainly in the form of crystalline iron-manganese oxide by the sequential extraction procedure, while Mo, As, and Zn are mainly in the residual form. Pb mainly exists in the form of carbonate, which is easy to be extracted. The orders of the apparent mobility and potential metal bioavailability of the selected residual metals are Pb>Cu>Zn>As>Mo>Fe.

A specialized myodural bridge named occipital-dural muscle in the narrow-ridged finless porpoise (Neophocaena asiaeorientalis).

A dense bridge-like tissue named the myodural bridge (MDB) connecting the suboccipital muscles to the spinal dura mater was originally discovered in humans. However, recent animal studies have revealed that the MDB appears to be an evolutionarily conserved anatomic structure which may have significant physiological functions. Our previous investigations have confirmed the existence of the MDB in finless porpoises. The present authors conducted research to expound on the specificity of the MDB in the porpoise Neophocana asiaeorientalis (N.asiaeorientalis). Five carcasses of N.asiaeorientalis, with formalin fixation, were used for the present study. Two of the carcasses were used for head and neck CT scanning, three-dimensional reconstructions, and gross dissection of the suboccipital region. Another carcass was used for a P45 plastination study. Also, a carcass was used for a histological analysis of the suboccipital region and also one was used for a Scanning Electron Microscopy study. The results revealed that the MDB of the N.asiaeorientalis is actually an independent muscle originating from the caudal border of the occiput, passing through the posterior atlanto-occipital interspace, and then attaches to the cervical spinal dura mater. Thus the so called MDB of the N.asiaeorientalis is actually an independent and uniquely specialized muscle. Based on the origin and insertion of this muscle, the present authors name it the 'Occipital-Dural Muscle'. It appears that the direct pull of this muscle on the cervical spinal dura mater may affect the circulation of the cerebrospinal fluid by altering the volume of the subarachnoid space via a pumping action.

Preparation of Black Ceramic Tiles Using Waste Copper Slag and Stainless Steel Slag of Electric Arc Furnace.

Copper slag and stainless steel slag of Electric Arc Furnace (EAF) are two typical metallurgical solid wastes, which contain a large number of valuables, such as Fe, Cr, and Cu. The transition metal elements in the waste slags, such as Cr and Fe, can be recycled as the coloring ions in the black ceramic tile. In this study, the Fe/Cr molar ratio in the raw materials of copper slag and stainless steel slag was adjusted, and the black ceramic tile was subsequently prepared by sintering. The results show that the optimum process parameters for the preparation of black ceramic tiles are the Fe/Cr molar ratio of 2.0, the sintering temperature of 1150 °C, and the sintering time of 30 min. The compressive strength of the black ceramic tile at optimum sintering conditions exceeds the minimum compressive strength of the Chinese national standard for standard polished tiles, and the concentrations of harmful elements, for example, Cr, Cu, Ni, As, Zn, Pb, and Cr(VI) are within the regulation thresholds specified by the Chinese national standard.

A one-pot synthesis of a monolithic Cu2O/Cu catalyst for efficient ozone decomposition.

Nowadays, it is necessary and challenging to prepare monolithic catalysts, which are ready for use, preventing the tedious and complicated integration procedure of the powder materials onto a porous substrate. Herein, Cu2O nanoparticles are successfully synthesized onto a porous Cu foam in one pot via the surface oxidation, coordination and precipitation reactions in a NH4OH and HCl solution, and the optimum synthesis conditions are a NH3 : HCl ratio of 1 : 0.9, oxidation temperature of 80 °C and time of 18 h. The obtained Cu2O/Cu catalyst (mostly <100 nm) shows a highly active O3 decomposition performance with >98% and >80% conversion efficiency in dry and 90% relative humidity air for >10 h at an O3 concentration of 20 ppm and a gas hourly space velocity of 12 500 h-1. The high efficiency can be attributed to the porous Cu foam providing a large contact area, abundant crystal defects in the nanometer-sized Cu2O materials serving as the active sites, and also to the Schottky barrier formed in the Cu2O/Cu interface facilitating the electron transfer for O3 degradation. All these results show the potency of the easily fabricated monolithic Cu2O/Cu catalyst for the highly efficient O3 contaminant removal.

Enhanced Plasmonic Resonance Characteristics of AgNRs-Gold Film Hybrid System.

In recent years, the plasma gap resonance maintained by metal-film-coupled nanostructures has attracted extensive attention. This mainly originates from its flexible control of the spectral response and significantly enhanced field strength at the nanoparticle-film junction. In the present study, the tunability of local surface plasmon resonances (LSPRs) of nanorods coupled to a gold film is studied theoretically. To this end, the plasmonic resonances in the nanostructure of individual silver nanorod-gold film (AgNR-film) with different parameters are investigated. Obtained results show that the refractive index sensitivity (S) of nanostructures to the environment increases as the aspect ratio (A r ) of nanostructures increase. It is found that when the aspect ratio (A r ) is set to 3.5, the figure of merit (FOM) is the highest. Moreover, the variation in the gap distances of the nanorod monomer-gold film, electric field distribution of nanorods dimer, and the corresponding impact on the gold film are studied. It is concluded that the gap size of nanostructures has an exponential correlation with the resonance wavelength. Considering the remarkable influence of the gap size and the surrounding medium environment on the spectral shift of AgNR-film nanostructures, potential applications of the structure as a refractive index sensor and biomolecule measurement are proposed.

Scanning Electron Microscopic Observation of Myodural Bridge in the Human Suboccipital Region.

STUDY DESIGN: A scanning electron microscopic study performed on three cadaveric specimens focused on the human suboccipital region, specifically, myodural bridge (MDB). OBJECTIVE: This study showed the connection form of the MDB among the suboccipital muscles, the posterior atlanto-occipital membrane (PAOM) and the spinal dura mater (SDM), and provided an ultrastructural morphological basis for the functional studies of the MDB. SUMMARY OF BACKGROUND DATA: Since the myodural bridge was first discovered by Hack, researches on its morphology and functions had been progressing continuously. However, at present, research results about MDB were still limited to the gross anatomical and histological level. There was no research report showing the MDB's ultrastructural morphology and its ultrastructural connection forms between PAOM and SDM. METHODS: A scanning electron microscope (SEM) was used to observe the connection of myodural bridge fibers with PAOM and SDM in atlanto-occipital and atlanto-axial interspaces, and the connection forms were analyzed. RESULTS: Under the SEM, it was observed that there were clear direct connections between the suboccipital muscles and the PAOM and SDM in the atlanto-occipital and atlanto-axial spaces. These connections were myodural bridge. The fibers of the myodural bridge merged into the spinal dura mater and gradually became a superficial layer of the spinal dura mater. CONCLUSION: MDB fibers merged into the SDM and became part of the SDM in the atlanto-occipital and atlanto-axial space. MDB could transfer tension and pulling force to the SDM effectively, during the contraction or relaxation of the suboccipital muscles. LEVEL OF EVIDENCE: N/A.

Size dependent allotropic transition of Co fine particles.

In order to investigate the size dependent allotropic transition of Co in wide size range, nanometer scaled (9 nm-350 nm) and micrometer sized (1 microm-18 microm) Co particles were prepared by laser induced pyrolysis, reduction as well as high temperature annealing treatment. In wide size range, from 9 nm to 10 microm for example, the crystal structure of the Co particles is dependent on their thermal history in which the particle involved in preparation or in annealing treatment. Only when the particle size is very large, much greater than 10 microm for example, the fcc-hcp transformation could occur during the cooling from high temperautre. According to the effect of surface energy on the martensitic transformation, the size dependent allotropic transformation of Co was discussed.