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The structural details of chromosomes have been of interest to researchers for many years, but how the metaphase chromosome is constructed remains unsolved. Divalent cations have been suggested to be required for the organization of chromosomes. However, detailed information about the role of these cations in chromosome organization is still limited. In the current study, we investigated the effects of Ca2+ and Mg2+ depletion and the reversibility upon re-addition of one of the two ions. Human chromosomes were treated with different concentrations of Ca2+and Mg2+. Depletion of Ca2+ and both Ca2+ and Mg2+ were carried out using 1, 2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid and ethylenediaminetetraacetic acid (EDTA), respectively. Chromosome structure was examined by fluorescence microscopy and scanning electron microscopy. The results indicated that chromosome structures after treatment with a buffer without Mg2+, after Ca2+ depletion, as well as after depletion of both Mg2+, and Ca2+, yielded fewer compact structures with fibrous chromatin than those without cation depletion. Interestingly, the chromatin of EDTA-treated chromosomes reversed to their original granular diameters after re-addition of either Mg2+ or Ca2+ only. These findings signify the importance of divalent cations on the chromosome structure and suggest the interchangeable role of Ca2+ and Mg2+.
We investigate the interstellar medium towards seven TeV gamma-ray sources thought to be pulsar wind nebulae using Mopra molecular line observations at 7 mm [CS(1–0), SiO(1–0, v = 0)], Nanten CO(1–0) data and the Southern Galactic Plane Survey/GASS Hi survey. We have discovered several dense molecular clouds co-located to these TeV gamma-ray sources, which allows us to search for cosmic rays coming from progenitor SNRs or, potentially, from pulsar wind nebulae. We notably found SiO(1–0, v = 0) emission towards HESS J1809–193, highlighting possible interaction between the adjacent supernova remnant SNR G011.0–0.0 and the molecular cloud at d ∼ 3.7 kpc. Using morphological features, and comparative studies of our column densities with those obtained from X-ray measurements, we claim a distance d ∼ 8.6 − 9.7kpc for SNR G292.2–00.5, d ∼ 3.5 − 5.6 kpc for PSR J1418–6058 and d ∼ 1.5 kpc for the new SNR candidate found towards HESS J1303–631. From our mass and density estimates of selected molecular clouds, we discuss signatures of hadronic/leptonic components from pulsar wind nebulae and their progenitor SNRs. Interestingly, the molecular gas, which overlaps HESS J1026–582 at d ∼ 5 kpc, may support a hadronic origin. We find however that this scenario requires an undetected cosmic-ray accelerator to be located at d < 10 pc from the molecular cloud. For HESS J1809–193, the cosmic rays which have escaped SNR G011.0–0.0 could contribute to the TeV gamma-ray emission. Finally, from the hypothesis that at most 20% the pulsar spin down power could be converted into CRs, we find that among the studied pulsar wind nebulae, only those from PSR J1809–1917 could potentially contribute to the TeV emission.
Data on the combination of foods consumed simultaneously at specific eating occasions are scarce, primarily due to a lack of assessment tools. We applied a recently developed meal coding system to multiple-day dietary intake data for assessing its ability to estimate food and nutrient intakes and characterise meal-based dietary patterns in the Japanese context. A total of 242 Japanese adults completed sixteen non-consecutive-day weighed dietary records, including 14 734 eating occasions (3788 breakfasts, 3823 lunches, 3856 dinners and 3267 snacks). Common food group combinations were identified by meal type to identify a range of generic meals. Dietary intake was calculated on the basis of not only the standard food composition database but also the substituted generic meal database. In total, eighty generic meals (twenty-three breakfasts, twenty-one lunches, twenty-four dinners and twelve snacks) were identified. The Spearman correlation coefficients between food group intakes calculated based on the standard food composition database and the substituted generic meal database ranged from 0·26 to 0·85 (median 0·69). The corresponding correlations for nutrient intakes ranged from 0·17 to 0·82 (median 0·61). A total of eleven meal patterns were established using principal components analysis, and these accounted for 39·1 % of total meal variance. Considerable variation in patterns was seen in meal type inclusion and choice of staple foods (bread, rice and noodles) and drinks, and also in meal constituents. In conclusion, this study demonstrated the usefulness of a meal coding system for assessing habitual diet, providing a scientific basis towards the development of simple meal-based dietary assessment tools.
The Magellanic Clouds offer the opportunity to obtain a spatially resolved view of external galaxies at reduced metallicity with no distance ambiguity. Our ALMA observations of the active star-forming region N83C in the Small Magellanic Cloud (SMC) revealed subparsec-scale molecular structures in 12CO and 13CO (2-1) emission Muraoka et al. (2017). We found strong CO peaks associated with Young Stellar Objects(YSOs) and derived a typical gas density of ∽104 cm−3 and gas temperature of 40-60 K from the excitation analysis. The high gas density and temperature are presumably due to the effect of the HII region under the low-metallicity environment. We have found that the column density ratios N(CI)/N(CO) are generally high throughout the cloud compared with the Galaxy, ranging from 0.2 to 2.0. A peak of the ratio is observed toward a CO peak associated with a massive protostar.
HESS J1614–518 and HESS J1616–508 are two tera-electron volt γ-ray sources that are not firmly associated with any known counterparts at other wavelengths. We investigate the distribution of interstellar medium towards the tera-electron volt γ-ray sources using results from a 7-mm-wavelength Mopra study, the Mopra Southern Galactic Plane CO Survey, the Millimetre Astronomer’s Legacy Team-45 GHz survey and [C i] data from the HEAT telescope. Data in the CO(1–0) transition lines reveal diffuse gas overlapping the two tera-electron volt sources at several velocities along the line of sight, while observations in the CS(1–0) transition line reveal several interesting dense gas features. To account for the diffuse atomic gas, archival H i data was taken from the Southern Galactic Plane Survey. The observations reveal gas components with masses ~103 to 105 M⊙ and with densities ~102 to 103 cm−3 overlapping the two tera-electron volt sources. Several origin scenarios potentially associated with the tera-electron volt γ-ray sources are discussed in light of the distribution of the local interstellar medium. We find no strong convincing evidence linking any counterpart with HESS J1614–518 or HESS J1616–508.
The aim of the study was to develop a family conflict scale for family caregivers of persons with dementia in long-term care facilities and to explore the relationship between family conflicts and family support.
The scale was developed through forward- and back-translations, interviews with 12 staff members in long-term care facilities, and cognitive interviews with 12 family caregivers who met operational definitions in this study. The test was conducted with 334 family caregivers and a retest was conducted with 318 family caregivers who had indicated willingness to participate further.
The internal consistency was relatively high for all subscales (Cronbach's α >0.87); sufficient retest reliability was demonstrated for all subscales (intraclass correlation coefficient >0.69). Confirmatory factor analysis supported a three-factor model. Convergent and discriminant validity for each of the family conflict scale subscales, family APGAR, and the Symptom Check List–90 Items–Revised were acceptable. Family caregivers who received no family assistance for caregiving perceived more conflict in their family than those receiving family assistance.
The Japanese version of the family conflict scale for family caregivers of persons with dementia in long-term care facilities was developed. The reliability and validity of the scale were verified. When providing support to family caregivers in long-term care facilities, it is necessary to consider the family from multiple viewpoints, including family conflicts and support conditions from other family members.
We report detections of thermal X-ray line emission and proper motions in the supernova remnant (SNR) RX J1713.7-3946, the prototype of the small class of synchrotron dominated SNRs. Based on deep XMM-Newton observations, we find clear line features including Ne Lyα, Mg Heα, and Si Heα from the central portion of the remnant. The metal abundance ratios suggest that the thermal emission originates from core-collapse SN ejecta arising from a relatively low-mass (≲20 M⊙) progenitor. In addition, using XMM-Newton observations on a 13 yr time interval, we have measured expansion in the southeastern rim to be ~0.75″ yr−1 or ~3500 km s−1 at a distance of 1 kpc. Given this, we derive an upstream density to be ~0.01 cm−3, compatible with the lack of thermal X-rays from the shocked ambient medium. We also estimate the age of the remnant to be ~1200–1600 yr, roughly consistent with the idea that RX J1713.7-3946 is the remnant of SN 393.
Large-bodied ectoparasites are often observed only in low numbers in the field. How such rarely found parasites persist and maintain viable populations has been an intriguing question inadequately addressed. The simplest hypothesis is the existence of distribution hot spots, and another, but not mutually exclusive, possibility is a form of metapopulation structure where local populations are effectively connected via dispersal. In this study, we conducted an intensive epidemiological survey of a piscicolid leech Taimenobdella amurensis to elucidate spatial population structure and potential dispersal of this rarely found parasite. Four years of potential-host screening (n = 20 664) from 28 tributaries and 10 main stem reaches in a mountain river system of Hokkaido, northern Japan, revealed that occurrences of T. amurensis (n = 1348) were confined to spring-fed tributaries. Since most spring-fed tributaries were small (<1 km in length), it would seem to be unlikely for the ectoparasite to form a persistent local population in each tributary. The main host fish was Dolly Varden charr, which is known to disperse among neighbouring tributaries. These findings suggest that, along with the host, the ectoparasite displays a potential metapopulation structure, in which host-dependent dispersion may overcome local extinction by keeping the local populations connected.
The risk of malaria outbreak surfaced in Vanuatu after Tropical Cyclone (TC) Pam in March 2015. In June and July 2015 we conducted malariometric surveys on the islands of Tanna, Aneityum, and Erromango in Tafea Province, where malaria elimination had been targeted, to determine if malaria incidence had increased after TC Pam. No Plasmodium infection was detected by microscopy and PCR in 3009 survey participants. Only 6·3% (190/3007) of participants had fever. Spleen rates in children aged ⩽12 years from Aneityum and Tanna were low, at 3·6% (14/387) and 5·3% (27/510), respectively. Overall bed net use was high at 72·8% (2175/2986); however, a significantly higher (P < 0·001) proportion of participants from Aneityum (85·9%, 796/927) reported net use than those from Tanna (67·1%, 751/1119) and Erromango (66·8%, 628/940). A recent decrease in malaria incidence in Tafea Province through comprehensive intervention measures had reduced the indigenous parasite reservoir and limited the latter's potential to spur an outbreak after TC Pam. The path towards malaria elimination in Tafea Province was not adversely affected by TC Pam.
By performing a global magnetohydrodynamical (MHD) simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular motion of the gas in the Galactic centre (GC) region. The radial distribution of the rotation frequency in the bulge region is not monotonic in general. The amplification of the magnetic field is enhanced in regions with stronger differential rotation, because magnetorotational instability and field-line stretching are more effective. The strength of the amplified magnetic field reaches ≳ 0.5 mG, and radial flows of the gas are excited by the inhomogeneous transport of angular momentum through turbulent magnetic field that is amplified in a spatially dependent manner. As a result, the simulated position-velocity diagram exhibits a time-dependent asymmetric parallelogram-shape owing to the intermittency of the magnetic turbulence; the present model provides a viable alternative to the bar-potential-driven model for the parallelogram shape of the central molecular zone. In addition, Parker instability (magnetic buoyancy) creates vertical magnetic structure, which would correspond to observed molecular loops, and frequently excited vertical flows. Furthermore, the time-averaged net gas flow is directed outward, whereas the flows are highly time dependent, which would contribute to the outflow from the bulge.
Various observations show peculiar features in the Galactic Center region, such as loops and filamentary structure. It is still unclear how such characteristic features are formed. Magnetic field is believed to play very important roles in the dynamics of gas in the Galaxy Center. Suzuki et al. (2015) performed a global magneto-hydrodynamical simulation focusing on the Galactic Center with an axisymmetric gravitational potential and claimed that non-radial motion is excited by magnetic activity. We further analyzed their simulation data and found that vertical motion is also excited by magnetic activity. In particular, fast down flows with speed of ~100 km/s are triggered near the footpoint of magnetic loops that are buoyantly risen by Parker instability. These downward flows are accelerated by the vertical component of the gravity, falling along inclined field lines. As a result, the azimuthal and radial components of the velocity are also excited, which are observed as high velocity features in a simulated position-velocity diagram. Depending on the viewing angle, these fast flows will show a huge variety of characteristic features in the position-velocity diagram.
We aimed to clarify the effect of low-carbohydrate diet (LCD) on renal function in overweight and obese individuals without chronic kidney disease (CKD). Literature searches were performed using EMBASE, MEDLINE and Cochrane Library until December 2015. We selected articles that reported human studies from their inception until December 2015 in English using the following searching terms: ‘Low carbohydrate diet’ AND (‘Clinical trial’ OR ‘Clinical study’ OR ‘Clinical investigation’ OR ‘Observational study’ OR ‘Cohort study’). We compared the effects of LCD on renal function, defined as change in estimated glomerular filtration rate (eGFR), assessed in randomised-controlled trials. We calculated the mean change in eGFR and the mean change in standard deviations by eGFR or creatinine clearance, and compared the mean change in eGFR and standard deviations in LCD with those in the control diet using fixed-effects models. We selected nine randomised controlled trials including 1687 participants (861 were fed LCD and 826 were fed the control diet). The mean change in eGFR in the LCD group was −4·7 to 24·0 ml/min per 1·73 m2 and that in the control diet group was −4·1 to 10·8 ml/min per 1·73 m2. The mean change in eGFR in the LCD group was greater than that in the control diet (0·13 ml/min per 1·73 m2; 95 % CI 0·00, 0·26). In the present meta-analysis, we identified that the increase in eGFR was greater in LCD compared with the control diet in overweight and obese individuals without CKD.
We give an expression of the motivic zeta function for a real polynomial function in terms of the Newton polyhedron of the function. As a consequence, we show that the weights are determined by the motivic zeta function for convenient weighted homogeneous polynomials in three variables. We apply this result to the blow-Nash equivalence.
New CO J=1–0 observations with NANTEN and NANTEN2 reveal that extensive collisions between two molecular clouds at relative velocity of 15 km s−1 triggered the O star formation in the Galactic mini-starbursts NGC 6357 and NGC 6334. Correlated/anti-correlated gas distributions and intermediate velocity features between the two clouds lend support for the cloud-cloud collision scenario. The timescale of the collision and high-mass star formation is as short as less than 0.5 Myrs, suggesting rapid O star formation.
High-mass stars usually form in giant molecular clouds (GMCs) as part of a young stellar cluster, but some isolated O/B stars are observed. What are the initial conditions that lead to the formation of these objects? The aim of this study is to measure the distribution and basic physical properties of the neutral gas associated with isolated intermediate- and high-mass young stellar objects (YSOs) in the Large Magellanic Cloud.
As part of the SAGE Spitzer Legacy program for the LMC, we have identified and confirmed YSOs using Spitzer IRAC photometry and IRS spectroscopy. By examining the spatial coincidence between the YSOs and 12CO(1–0) emission detected by the NANTEN mapping survey, we identified more than one hundred intermediate/massive YSOs in the LMC that appear to be isolated, i.e. not associated with CO emission. Deeper follow-up CO observations by our team with the higher resolution by Mopra Telescope (beam=30”) detected CO emission at the YSO positions for ~80% of the isolated LMC YSOs. We obtained ALMA data of some of the targets during Cycle 2. We targeted a small but representative (in terms of their association with neutral gas tracers) sample of the isolated high-mass YSOs that we have been studying in the LMC. All of our 12 targets are separated by more than 200 pc from known CO clouds. Our analysis of the ALMA data shows that a compact molecular cloud whose mass is a few thousand solar masses or smaller is associated with most of the YSOs.
The superbubble (SB) 30 Dor C with the strong non-thermal X-ray emission is one of the best targets for study of the cosmic-ray (CR) acceleration. We investigated X-ray spectral properties of the SB with a high spatial resolution of ~10 pc. Consequently, the spectra in the east regions can be described with a combination of absorbed thermal and non-thermal models while the spectra in the west regions can be fitted with an absorbed non-thermal model. We found that the observed photon index and intensity in 2-10 keV show variations of 2.0-3.5 and (0.6-8.0) × 10−7 erg s−1 cm−2 str−1, respectively. The results are possibly caused by the spatial variation of the CR acceleration efficiency and/or the circumstellar environment.
It is crucially important to observe dense cores in order to investigate the initial condition of star formation since protostars are formed via dynamical collapse of dense cores, inhering the physical properties from their natal dense cores. Here we present the results of ALMA Cycle 0 and Cycle 1 observations of dust continuum emission and molecular rotational lines toward a dense core, MC27 (aka L1521F), which is considered to be very close to the first protostellar core phase. We revealed the spatial/velocity structures of the core are very complex and and suggest that the star formation is highly dynamical.
RCW 38 is the youngest super star cluster in the Galaxy and is located at a distance of 1.7 kpc. Molecular observations revealed that the cluster is associated with two molecular clouds having velocity difference of 12 km s−1. We interpret that the two clouds are colliding with each other and the collision triggered the cluster formation. The natal molecular gas still survives within ~ 0.5 pc of the central O stars which have an age of 0.1 Myrs as inferred from the collision morphology. We suggest that the high column density of one of the clouds 1023 cm−2 enabled formation of ~ 20 O stars in the cluster center and discuss the implications on massive cluster formation.
Although habitual seaweed consumption in Japan would suggest that iodine intake in Japanese is exceptionally high, intake data from diet records are limited. In the present study, we developed a composition database of iodine and estimated the habitual intake of iodine among Japanese adults. Missing values for iodine content in the existing composition table were imputed based on established criteria. 16 d diet records (4 d over four seasons) from adults (120 women aged 30–69 years and 120 men aged 30–76 years) living in Japan were collected, and iodine intake was estimated. Habitual intake was estimated with the Best-power method. Totally, 995 food items were imputed. The distribution of iodine intake in 24 h was highly skewed, and approximately 55 % of 24 h values were < 300 μg/d. The median iodine intake in 24 h was 229 μg/d for women and 273 μg/d for men. All subjects consumed iodine-rich foods (kelp or soup stock) on one or more days of the sixteen survey days. The mean (median) habitual iodine intake was 1414 (857) μg/d for women and 1572 (1031) μg/d for men. Older participants had higher intake than younger participants. The major contributors to iodine intake were kelp (60 %) and soup stock (30 %). Habitual iodine intake among Japanese was sufficient or higher than the tolerable upper intake level, particularly in older generations. The association between high iodine intake as that observed in the present study and thyroid disease requires further study.
Late-onset psychosis (LOP) has become increasingly prevalent in the clinical setting, especially in the highly aged society, due to the increasing numbers of older people and its disruptive impact on the lives of patients and caregivers. Although previous studies have identified some of the features of LOP (Webster and Grossberg, 1998; Mitford et al., 2010; Tan and Seng, 2012), some of the previous studies did not include patients with dementia and mood disorders. This study addresses the features of LOP in consecutive outpatients to provide information that supports the differential diagnosis.