Extending coherence time of macro-scale diamond magnetometer by dynamical decoupling with coplanar waveguide resonator

Ultimate sensitivity for quantum magnetometry using nitrogen-vacancy (NV) centers in a diamond is limited by a number of NV centers and coherence time. Microwave irradiation with a high and homogeneous power density for a large detection volume is necessary to achieve a highly sensitive magnetometer. Here, we demonstrate a microwave resonator to enhance the power density of the microwave field and an optical system with a detection volume of 1.4 × 10^-3 mm³. The strong microwave field enables us to achieve 48 ns Rabi oscillation which is sufficiently faster than the phase relaxation time of NV centers. This system combined with a decoupling pulse sequence, XY16, extends the spin coherence time (T ₂) up to 27 times longer than that with a spin echo method. Consequently, we obtained an AC magnetic field sensitivity of 10.8 pt/ Hz using the dynamical decoupling pulse sequence.

Improving the electron spin properties of nitrogen-vacancy centres in nanodiamonds by near-field etching

The nitrogen-vacancy (NV) centre in diamond is a promising candidate for quantum computing applications and magnetic sensing applications, because it is an atomic-scale defect with stable coherence time (T2) and reliable accessibility at room temperature. We demonstrated a method for improving the NV spin properties (the full width half maximum (FWHM) value of the magnetic resonance spectrum and T2) through a near-field (NF) etching method under ambient conditions. The NF etching method, based on a He-Cd ultraviolet laser (325 nm), which is longer than the absorption edge of the oxygen molecule, enabled selective removal of defects on the nanodiamond surface. We observed a decrease in the FWHM value close to 15% and an increase in T2 close to 25%. Since our technique can be easily reproduced, a wide range of NV centre applications could be improved, especially magnetic sensing applications. Our results are especially attractive, because they have been obtained under ambient conditions and only require a light source with wavelength slightly above the O2 absorption edge.

Postnatal relative adrenal insufficiency results in methylation of the glucocorticoid receptor gene in preterm infants: a retrospective cohort study

Background

To investigate the relationship between early-life stress and glucocorticoid receptor (GR) gene methylation, which may result in long-lasting neurodevelopmental impairment, we performed a longitudinal analysis of the methylation ratio within the GR gene promoter 1F region using next-generation sequencing in preterm infants.

Cell-free DNA was extracted from the frozen serum of 19 preterm birth infants at birth and at 1 and 2 months after birth. All were admitted to the neonatal intensive care unit of Juntendo University Shizuoka Hospital between August 2014 and May 2016 and suffered from chronic lung disease (CLD).

Through bisulfite amplicon sequencing using an Illumina Miseq system and Bismark-0.15.0 software, we identified the rate of cytosine methylation.

Results

Patients’ sex and body weight standard deviation were extracted as the associated independent variables at birth. Sex, glucocorticoid administration for treating CLD, and postnatal invasive procedures (surgical operation and blood sampling) were extracted as the associated independent variables at 1 month. Methylation rates increased significantly between postnatal 1 and 2 months at 9 of the 39 CpG sites. Postnatal glucocorticoid administration to treat circulatory collapse was the most-associated independent variable with a positive regression coefficient for a change in methylation rate at these nine CpG sites. It also influenced the methylation ratio at 22 of the 39 CpG sites at 2 months of age. The standard deviation (SD) score at birth was extracted as an independent variable, with a negative regression coefficient at 9 of the 22 CpG sites together with glucocorticoid administration.

Conclusions

The results of this study indicate that a prenatal environment that results in intrauterine growth restriction and postnatal relative adrenal insufficiency requiring glucocorticoid administration leads to GR gene methylation. That, in turn, may result in neurodevelopmental disabilities.

Influence of pharyngeal airway respiration pressure on Class II mandibular retrusion in children: A computational fluid dynamics study of inspiration and expiration

OBJECTIVES

To examine the influence of negative pressure of the pharyngeal airway on mandibular retraction during inspiration in children with nasal obstruction using the computational fluid dynamics (CFD) method.

SETTING AND SAMPLE POPULATION

Sixty-two children were divided into Classes I, II (mandibular retrusion) and III (mandibular protrusion) malocclusion groups.

MATERIAL AND METHODS

Cone-beam computed tomography data were used to reconstruct three-dimensional shapes of the nasal and pharyngeal airways. Airflow pressure was simulated using CFD to calculate nasal resistance and pharyngeal airway pressure during inspiration and expiration.

RESULTS

Nasal resistance of the Class II group was significantly higher than that of the other two groups, and oropharyngeal airway inspiration pressure in the Class II (-247.64 Pa) group was larger than that in the Class I (-43.51 Pa) and Class III (-31.81 Pa) groups (P<.001). The oropharyngeal airway inspiration-expiration pressure difference in the Class II (-27.38 Pa) group was larger than that in the Class I (-5.17 Pa) and Class III (0.68 Pa) groups (P=.006).

CONCLUSION

Large negative inspiratory pharyngeal airway pressure due to nasal obstruction in children with Class II malocclusion may be related to their retrognathia.

A higher incidence of cleavage failure in oocytes containing smooth endoplasmic reticulum clusters

PURPOSE

In human oocytes, sERCs are one of the dysmorphic phenotypes that have been reported. Significantly reduced pregnancy rates and a comparatively higher number of abnormities in live births appear to be associated with the presence of sERCs in oocytes. However, some reports have shown that healthy babies can be born, without any reduced pregnancy rates, from oocytes observed to contain sERCs. Thus, the clinical and scientific significance of oocytes that harbor sERCs remains controversial.

METHODS

The presence of sERCs was evaluated using a time-lapse system while studying the dynamic changes within oocytes and embryos. Logistic regression analysis was carried out to explore the independent variables for meiotic and mitotic cleavage failure..

RESULTS

The incidence of mitotic cleavage failure and the incidence of meiotic cleavage failure during the second polar body extrusion in oocytes with sERCs were found to be significantly higher than that in oocytes without sERCs. Furthermore, ICSI was found to have a greater frequency of meiotic failure than IVF.

CONCLUSIONS

In cases of cleavage failure, an embryonic cell could become tetraploid and may induce abnormal chromosomal configurations. Some cells exposed to cleavage failure may become trophectoderm cells and form placental abnormalities. Even if they develop into trophectoderm cells, the ICM can be susceptible to further cleavage failure and may in turn cause further aneuploidy. For these reasons, it is important to monitor pregnancies and births derived from oocytes that contained sERCs.

The Beneficial Effect of Carboxylated Poly-L-Lysine on Cryosurvival of Vitrified Early Stage Embryos

BACKGROUND

In the vitrification of embryos, dimethyl sulfoxide (DMSO) is one of the most effective cryoprotectant agents (CPAs), but cytotoxic effects of DMSO on embryos are well known. Carboxylated poly-L-lysine (CPLL) has been identified as an effective cryoprotectant of cultured cell lines and mammalian oocytes.

OBJECTIVE

To evaluate the efficacy and safety of CPLL as a CPA for developmental stage embryos.

MATERIALS AND METHODS

Mouse 8-cell embryos and blastocysts were vitrified with ethylene glycol (EG), DMSO/EG, or CPLL/EG and the developmental potency assessed in vitro.

RESULTS

In 8-cell embryos, there were no differences between the levels of survival and developmental progress into the blastocyst stage in each solution. At the blastocyst stage, the proportion of dead cells was significantly higher in the EG compared with other solutions. In contrast, there were no differences between the DMSO/EG and CPLL/EG.

CONCLUSION

These results indicate that CPLL can be used as a replacement for DMSO in the vitrification of mouse embryos.

Quantitative assessment of provability of radiation-related cancers considering unavoidable existence of unadjusted risk factors

The attribution of stochastic effects to exposure to ionizing radiation has been qualitatively discussed by introducing two distinct concepts of provability and probability. This study aims to develop a method of quantitatively assessing the provability of radiation-related cancers. To this end, the 'minimum provable dose' (MPD) was developed and applied to actual cancer mortality in Japan. The background lifetime risk of cancer mortality was calculated for the esophagus, stomach, colon, liver, lungs, skin, breasts, ovaries, bladder, and bone marrow as well as the age-specific risk coefficients reproducing those given in the 2007 Recommendations of the International Commission on Radiological Protection (ICRP). Comparing the relative ratio of MPDs, which was defined herein as the 'provability index' (PI), we quantitatively ranked radiation-related cancers for different tissues and organs predicated on provability for ages of 10, 30, 50, and 0-85+  years at exposure. We discuss the radiological protection of male emergency workers focusing on cancers highly prioritized according to the ranking (i.e. colon, bone marrow, and bladder). The present study proposed the system to quantitatively evaluate the level of radiological protection taking into account the variations of the background cancer risk on the provability of radiation-related cancers.

Case of severe alcoholic hepatitis treated with granulocytapheresis

Severe alcoholic hepatitis (AH) has a high mortality, and it is associated with encephalopathy, acute renal failure, sepsis, gastrointestinal bleeding, and endotoxemia. The 28-d mortality remains poor (34%-40%), because no effective treatment has been established. Recently, corticosteroids (CS) have been considered effective for significantly improving the prognosis of those with AH, as it prevents the production of pro-inflammatory cytokines. However, CS are not always appropriate as an initial therapeutic option, such as in cases with an infection or resistance to CS. We describe a patient with severe AH complicated by a severe infection caused by the multidrug resistance bacteria (Pseudomonas aeruginosa), and was successfully treated with granulocytapheresis monotherapy without using CS. The experience of this case will provide understanding of the disease and information treating cases without using CS.

Localized Hepatic Tuberculosis with Imaging Changes Caused by the Progression of Tuberculosis

Localized hepatic tuberculosis (LHTB) is difficult to diagnose preoperatively, and most cases of LHTB are diagnosed based on pathological findings. A relationship between imaging features and the pathological stage of hepatic tuberculosis (TB) has recently been reported, which could aid in the diagnosis of hepatic TB. We herein present a case study of a patient with LHTB diagnosed postoperatively who demonstrated imaging changes due to the progression of TB. An awareness of the presence of LHTB might have permitted a preoperative diagnosis. This is the first report of an LHTB patient who exhibited imaging changes during the course of the disease.

A low-pungency S3212 genotype of Capsicum frutescens caused by a mutation in the putative aminotransferase (p-AMT) gene

The purpose of this study was to identify the genetic mechanism underlying capsinoid biosynthesis in S3212, a low-pungency genotype of Capsicum frutescens. Screening of C. frutescens accessions for capsaicinoid and capsiate contents by high-performance liquid chromatography revealed that low-pungency S3212 contained high levels of capsiate but no capsaicin. Comparison of DNA coding sequences of pungent (T1 and Bird Eye) and low-pungency (S3212) genotypes uncovered a significant 12-bp deletion mutation in exon 7 of the p-AMT gene of S3212. In addition, p-AMT gene transcript levels in placental tissue were positively correlated with the degree of pungency. S3212, the low-pungency genotype, exhibited no significant p-AMT transcript levels, whereas T1, one of the pungent genotypes, displayed high transcript levels of this gene. We therefore conclude that the deletion mutation in the p-AMT gene is related to the loss of pungency in placental tissue and has given rise to the low-pungency S3212 C. frutescens genotype. C. frutescens S3212 represents a good natural source of capsinoids. Finally, our basic characterization of the uncovered p-AMT gene mutation should contribute to future studies of capsinoid biosynthesis in Capsicum.

Teaching liaison psychiatry and clinical practice of psychosomatic medicine in the general hospital

One of the recent trends in the general hospital is the increase of psychiatric units and the number of psychiatrists working therein. Thus the psychiatrist has had greater opportunities to participate as a member of a clinical team in the care of patients of other units. Accordingly, daily cooperation with other specialties casts him into new roles which transcend those of the traditional psychiatric consultant. The role of liasion psychiatrist involves the complex relations of doctor--nurse--patient--family, interdepartmental relations, communications and so on. By improving these relationships he tries to bring about a more holistic approach in the general hospital.