Latent ion tracks were finally observed in diamond

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Balloon venoplasty for disdialysis syndrome due to pacemaker-related superior vena cava syndrome with chylothorax post-bacteraemia: A case report

BACKGROUND

Although superior vena cava (SVC) syndrome has also been reported as a late complication of pacemaker (PM) implantation, acute onset of SVC syndrome caused by disdialysis syndrome in patients with PM implantation is very rare. There are no specific therapies or guidelines.

CASE SUMMARY

A 96-year-old woman receiving dialysis was implanted with a PM due to sick sinus syndrome. She was referred to our facility for chest discomfort experienced during dialysis. Upon examination, unilateral pleural effusion on the right side was cloudy with a foul odour. The patient was diagnosed with pyothorax and treated with antibiotics. After the effusion was reduced, it gradually reaggravated and remained cloudy. In this case, SVC syndrome, which is generally considered a late complication after PM implantation, rapidly developed following the bacteraemia, resulting in impaired venous return, chylothorax, and disdialysis syndrome. After catheter intervention for SVC stenosis, the patient's symptoms promptly improved. The patient has been recurrence-free for a year.

CONCLUSION

Acute SVC syndrome can cause dysdialysis in PM-implanted patients. Catheter intervention alone has improved this condition for a traceable period.

Impact of the lateral skeletal stability following bilateral sagittal split ramus osteotomy for mandibular asymmetry

This study evaluated the stability of bilateral sagittal split ramus osteotomy (BSSRO) associated with positional plagiocephaly and temporal and masseter muscles using posteroanterior cephalogram analysis and three-dimensional computed tomography (3D-CT). This retrospective cohort study included 31 patients who underwent BSSRO for mandibular asymmetry. The cranial vault asymmetry index (CVAI) and the cephalic index were used as indicators of positional plagiocephaly. The distance from the vertical reference line to the menton (Me) was measured on posteroanterior cephalograms immediately and 1 year after surgery, and postoperative stability was assessed. Temporal and masseter muscles were constructed from 3D-CT data and their volumes were measured. Simple regression analysis showed a significant correlation between postoperative changes in the vertical reference line to the Me and the CVAI (R = 0.56, p = 0.001), the amount of surgical movement in the vertical reference line to the Me (R = 0.41, p = 0.023), and the variable temporal muscle volume (R = 0.27, p = 0.028). There was no significant correlation between postoperative changes in the vertical reference line to the Me and the cephalic index (R = 0.093, p = 0.62) and variable masseter muscle volume (R = 0.16, p = 0.38). According to multivariate analysis, CVAI (p = 0.003) and amount of surgical movement in the vertical reference line to the Me (p = 0.014) were significant predictors of postoperative change in the vertical reference line to the Me. Positional plagiocephaly and amount of surgical movement influence lateral skeletal stability following BSSRO for mandibular asymmetry.

Combined Exercise and Education Program: Effect of Smaller Group Size and Longer Duration on Physical Function and Social Engagement among Community-Dwelling Older Adults

Background

Exercise, education, and social engagement are critical interventions for older adults for a healthy life expectancy and to improve their physical function.

Objective

To conduct a combined exercise and education (CEE) program for improved social engagement and physical function of older adults.

Design

Based on a short-term program we conducted in our previous study, in this study, the program was conducted for half the number of participants of the earlier study but for a longer duration.

Setting

A community of older adults in Ami, Japan, was the setting of the study.

Participants

23 healthy older adults >65 years living in the community were the participants in the study.

Interventions

Five 80-minute sessions conducted once in two weeks comprised 60-min exercise instruction and 20-min educational lectures per session on health. We examined the improvement in physical and social engagement before and after participation. Physical function and health-related questionnaire data were collected before and after the program.

Results

Data analysis from 15 participants showed improved physical performance but no effect on social engagement.

Conclusions

A higher program frequency, rather than program duration, may be vital to improving exercise performance and social engagement and maximizing the effects of high group cohesion in small groups. Further studies are needed to develop more effective interventions to extend healthy life expectancy.

Molecular detection of Lotmaria passim in honeybees in Japan

Crithidia mellificae (C. mellificae) and Lotmaria passim (L. passim) are trypanosomatids that infect Apis mellifera. We analyzed the prevalence of C. mellificae and L. passim in six regions of Japan from 2018 to 2019. The detection rate of C. mellificae was 0.0% in all regions, whereas L. passim was detected in 16.7%-66.7% of the honeybees. L. passim was detected at a significantly lower rate in the Cyugoku-Shikoku region than in other regions. Furthermore, phylogenetic analysis of the internal transcribed spacer 1 (ITS1) locus of related species was performed. All the samples in this study could be assigned to the L. passim clade. This study reveals that L. passim infection is predominantly prevalent in Japan. Further epidemiological surveys are needed to clarify the prevalence of C. mellificae infection in honeybees in Japan.

Comparison of risk factors for SARS-CoV-2 infection among healthcare workers during Omicron and Delta dominance periods in Japan

BACKGROUND

The risk factors for coronavirus disease (COVID-19) among healthcare workers (HCWs) might have changed since the emergence of the highly immune evasive Omicron variant.

AIM

To compare the risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among HCWs during the Delta- and Omicron-predominant periods.

METHODS

Using data from repeated serosurveys among the staff of a medical research centre in Tokyo, two cohorts were established: Delta period cohort (N = 858) and Omicron period cohort (N = 652). The potential risk factors were assessed using a questionnaire. Acute/current or past SARS-CoV-2 infection was identified by polymerase chain reaction or anti-nucleocapsid antibody tests, respectively. Poisson regression was used to calculate the risk ratio (RR) of infection risk.

FINDINGS

The risk of SARS-CoV-2 infection during the early Omicron-predominant period was 3.4-fold higher than during the Delta-predominant period. Neither working in a COVID-19-related department nor having a higher degree of occupational exposure to SARS-CoV-2 was associated with an increased infection risk during both periods. During the Omicron-predominant period, infection risk was higher among those who spent ≥30 min in closed spaces, crowded spaces, and close-contact settings without wearing mask (≥3 times versus never: RR: 6.62; 95% confidence interval: 3.01-14.58), whereas no such association was found during the Delta period.

CONCLUSION

Occupational exposure to COVID-19-related work was not associated with the risk of SARS-CoV-2 infection in the Delta or Omicron period, whereas high-risk behaviours were associated with an increased infection risk during the Omicron period.

End-of-Life Care of Acute Myeloid Leukemia Compared with Aggressive lymphoma in Patients Who Are Eligible for Intensive Chemotherapy: An Observational Study in a Japanese Community Hospital

Background

Patients with hematological malignancies (HMs) are reported to receive more aggressive care at the end of life (EOL) than patients with solid tumors. However, the reasons behind this occurrence are not fully understood.

Objectives

To examine whether the care at EOL for HMs is mainly because of the disease characteristics or hematologists' attitudes and systems of care, we compared the EOL care of patients with acute myeloid leukemia (AML) and diffuse large B cell lymphoma (DLBCL).

Design

We retrospectively analyzed the EOL care of patients with AML and DLBCL younger than 80 years who were receiving combination chemotherapy at a city hospital in Japan.

Results

Fifty-nine patients with AML and 65 with DLBCL were included. Those with AML received chemotherapy more often within their last 30 days (48% vs. 19%, p < 0.001) and 14 days (37% vs. 1.5%, p < 0.001) of life, and consulted the palliative team less frequently (5.3% vs. 29%, p < 0.001). In the last 3 years, the mortality rate in hematological wards decreased from 74% to 29% in the DLBCL group, but only from 95% to 90% in the AML group. In multivariate analysis, AML (odds ratio [OR] 0.065) and death before 2018 (OR, 0.077) were significant factors associated with reduced referrals to specialized palliative teams.

Conclusion

Patients with AML tend to have lesser access to specialized palliative care and fewer options for their place of death than those with DLBCL. Detailed EOL care plans are needed for these patients, considering the characteristics of the disease.

Urine osmolality predicts worsening renal function and poor prognosis in acute decompensated heart failure

Background/Purpose

Worsening renal function (WRF) can sometimes occur in the patients with acute decompensated heart failure (ADHF) and increase the risk of morbidity and mortality (1). In a previous study, it was reported that fractional excretion of sodium (FENa) reflects net sodium reabsorption from nephron segments and predicts WRF during treating ADHF (2). On the other hand, recently the new drugs which approach urine concentration mechanism and affect urine osmolality (U-OSM), such as tolvaptan and sodium-glucose cotransporter-2 inhibitor, have begun to be widely used as treatment of heart failure. Thus, we focused on U-OSM, which reflects not only sodium handling but also water excretion controlled by the collecting duct, and evaluated the association between WRF and U-OSM. Moreover, previous studies have demonstrated that FENa, fractional excretion of urea nitrogen and transtubular potassium concentration gradient are markers for long-term prognosis in patients with ADHF (3–5). Therefore, we also studied whether U-OSM can predict prognosis in ADHF.

Methods

A total of 157 patients admitted to our hospital because of a primary diagnosis of ADHF from February 2020 through July 2021 were retrospectively reviewed. U-OSM in the spot urinary samples were examined within 72 hours after admission. U-OSM was calculated based on the following validated formula (6): U-OSM = 1.07 × {2 × [urine sodium (mEq/L)] + [urine urea nitrogen (mg/dL)]/2.8 + [urine creatinine (mg/dl)] × 2/3} + 16.2. The primary outcome was the occurrence of WRF during hospitalization. WRF was defined as increased serum creatinine ≥0.3 mg/dL from baseline (7). The secondary outcome was the occurrence of ADHF readmission and all-cause death within 180 days after discharge.

Results

Primary Outcome. WRF developed in 46% of all patients. In the patients that developed WRF during hospitalization, U-OSM was significantly lower than in the patients without WRF (366±106 mOsm/L versus 430±128 mOsm/L; P&lt;0.001). Receiver operating characteristic curve analysis revealed the optimal cutoff values of U-OSM was 403 mOsm/L (AUC 0.64; 95% CI: 0.56–0.72; P&lt;0.001) to predict the WRF (Figure 1). On multivariable logistic regression analysis, U-OSM (OR, 1.99, 95% CI: 1.27–3.12; p=0.003) and serum creatinine (OR, 1.00, 95% CI: 0.99–1.00; P=0.009) were independent predictors of WRF.

Secondary Outcome. There were 34 patients (22%) readmitted and 9 patients (6%) died within 180 days after discharge. ROC curve analysis revealed the optimal cutoff values of U-OSM as 349 mOsm/L (C-statistic 0.74; 95% CI: 0.65–0.83; P&lt;0.001) to predict ADHF readmission and all-cause death within 180 days (Figure 2A). On Kaplan-Meier analysis, the secondary outcome was significantly higher in patients with U-OSM&lt;349 mOsm/L (u-OSM≥349, 57%, U-OSM&lt;349, 43%; HR, 0.99; 95% CI: 0.99–1.00, P&lt;0.001) (Figure 2B).

Conclusion

U-OSM on admission may be a predictor of WRF and a prognostic marker in ADHF patients.

Funding Acknowledgement

Type of funding sources: None.

A Retrospective Analysis of R-MPV Plus Response-adapted Whole-brain Radiotherapy for Elderly Patients with Primary Central Nervous System Lymphoma

Objective Few reports have described the real-world outcomes of rituximab, methotrexate (MTX), procarbazine, and vincristine (R-MPV) plus response-adapted whole-brain radiotherapy (WBRT) for elderly patients with primary central nervous system lymphoma (PCNSL). We evaluated the outcome of this regimen. Methods We evaluated >60-year-old patients with newly diagnosed PCNSL who received R-MPV plus WBRT from January 2010 to December 2019 at Toyohashi Municipal Hospital. The patients' characteristics, regimen enforcement, response rate, survival, and toxicity were analyzed. Patients Ten patients were consecutively enrolled. Their median age was 69 years old, and 60% had a performance status of 3 or 4 before induction therapy. Results Seven patients achieved a complete response after induction, and all 10 patients achieved a complete response after consolidation. Seven received reduced-dose WBRT at 23.4 Gy, and 2 received WBRT at 45 Gy. The median follow-up was 44.4 months; the 3-year progression-free survival and overall survival rates were 60% and 80%, respectively; and the cumulative incidence of relapse was 40%. The incidence of symptomatic delayed neurotoxicity was 70%. Of the 7 patients who received reduced-dose WBRT, 4 (57%) developed delayed neurotoxicity, including 1 severely affected patient. Only one patient survived without relapse and delayed neurotoxicity. The ratio of patients who developed relapse or delayed neurotoxicity that impaired daily life was 33% and 100% in the MTX high- and low-intensity groups, respectively. Conclusion This regimen in elderly patients is unsatisfactory because of delayed neurotoxicity. We should consider maintaining an adequate MTX intensity, postponing or minimizing WBRT, and choosing high-dose consolidation therapy for select patients.

Reciprocal role of PLAP-1 in HIF-1α-mediated responses to hypoxia

OBJECTIVE

To investigate the mutual regulation of hypoxia-inducible factor (HIF)-1α activity and periodontal ligament-associated protein-1 (PLAP-1) expression in human periodontal ligament cells (HPDLs).

BACKGROUND

Cellular responses to hypoxia regulate various biological events (e.g., inflammation and tissue regeneration) through activation of HIF-1α. PLAP-1, an extracellular matrix protein preferentially expressed in the periodontal ligament, plays important roles in the functions of HPDLs. Although PLAP-1 expression has been demonstrated in hypoxic regions, the involvement of PLAP-1 in responses to hypoxia has not been revealed.

METHODS

HPDLs were cultured under normoxic (20% O₂ ) or hypoxic (1% O₂ ) conditions with or without deferoxamine mesylate (chemical hypoxia inducer) or chetomin (HIF signaling inhibitor). Expression levels of PLAP-1 and HIF-1α were examined by real-time reverse transcription-polymerase chain reaction and western blot analysis. Luciferase reporter assays of HIF-1α activity were performed using 293T cells stably transfected with a hypoxia response element (HRE)-containing luciferase vector in the presence or absence of recombinant PLAP-1 or PLAP-1 gene transfection.

RESULTS

Cultivation under hypoxic conditions elevated the gene and protein expression levels of PLAP-1 in HPDLs. Deferoxamine mesylate treatment also enhanced PLAP-1 expression in HPDLs. Hypoxia-induced PLAP-1 expression was significantly suppressed in the presence of chetomin. PLAP-1-suppressed HPDLs showed increased HIF-1α accumulation in the nucleus during culture under hypoxic conditions, but not in the presence of recombinant PLAP-1. In the presence of recombinant PLAP-1, hypoxia-induced HRE activity of 293T cells was significantly suppressed in a dose-dependent manner. Transfection of the PLAP-1 gene resulted in a significant reduction of HRE activity during culture under hypoxic conditions.

CONCLUSION

PLAP-1 expression is upregulated under hypoxic conditions through HIF-1α activation. Moreover, hypoxia-induced PLAP-1 expression regulates HIF-1α signaling.

Pre-operative endovascular coil embolisation for chronic pulmonary aspergillosis

OBJECTIVE: To retrospectively evaluate the clinical outcomes of pre-operative endovascular coil embolisation (ECE) for chronic pulmonary aspergillosis (CPA).METHODS: We evaluated surgical patients with CPA between November 2016 and April 2020. Pre-operative ECE for CPA with severe adhesions was selectively performed to reduce intra-operative blood loss. ECE procedures, operative procedures, intra-operative blood loss and complications were evaluated.RESULTS: Twenty-eight patients (21 males and 7 females; median age: 55 years) were included in the study. Of the 28 patients, 8 (28.6%) underwent pre-operative ECE. Technical success rate in pre-operative ECE was 100%. The median time required for ECE procedures was 123 min. The median number of vessels embolised per procedure was 2.5. The median period between embolisation and surgery was 5 days. Major complications were observed in three patients (10.7%). There were no significant differences between patients with and without pre-operative ECE in operative time (284 vs. 365 min, respectively, P = 0.7602) and intra-operative blood loss (294 vs. 228 mL, respectively, P = 0.8987).CONCLUSIONS: Pre-operative ECE for CPA appears to be feasible and safe; however, its role in reducing intra-operative blood loss needs further investigation.

DNAJA1 promotes cancer metastasis through interaction with mutant p53

Accumulation of mutant p53 (mutp53) is crucial for its oncogenic gain of function activity. DNAJA1, a member of J-domain containing proteins or heat shock protein 40, is shown to prevent unfolded mutp53 from proteasomal degradation. However, the biological function of DNAJA1 remains largely unknown. Here we show that DNAJA1 promotes tumor metastasis by accumulating unfolded mutp53. Levels of DNAJA1 in head and neck squamous cell carcinoma (HNSCC) tissues were higher than those in normal tissues. Knockdown of DNAJA1 in HNSCC cell lines carrying unfolded mutp53 significantly decreased the levels of mutp53, filopodia/lamellipodia formation, migratory potential, and active forms of CDC42/RAC1, which were not observed in HNSCC cells with DNA contact mutp53, wild-type p53, or p53 null. Such mutp53-dependent functions of DNAJA1 were supported by the observation that DNAJA1 selectively bound to unfolded mutp53. Moreover, DNAJA1 knockdown in HNSCC cells carrying unfolded mutp53 inhibited primary tumor growth and metastases to the lymph nodes and lungs. Our study suggests that DNAJA1 promotes HNSCC metastasis mainly in a manner dependent on mutp53 status, suggesting DNAJA1 as a potential therapeutic target for HNSCC harboring unfolded mutp53.

Ion tracks in silicon formed by much lower energy deposition than the track formation threshold

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C₆₀) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C₆₀ ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C₆₀ irradiation. Furthermore, the tracks formed by 6 MeV C₆₀ irradiation consisted of damaged crystalline, while those formed by 40 MeV C₆₀ irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of S_e below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

The ELFIN Mission

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93^∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (T_orbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (T_spin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

Matrix-material dependence on the elongation of embedded gold nanoparticles induced by 4 MeV C60 and 200 MeV Xe ion irradiation

We report the elongation of embedded Au nanoparticles (NPs) in three different matrices, i.e. amorphous carbon (a-C), crystalline indium tin oxide (In_xSn_1-xO_z; ITO) and crystalline calcium fluoride (CaF₂), under irradiations of 4 MeV C₆₀ ⁺ cluster ions and 200 MeV Xe¹⁴⁺ ions. Under 4 MeV C₆₀ cluster irradiation, strong sputtering is induced in CaF₂ layer so that the whole the layer was completely lost at a fluence of 5 × 10¹³ ions cm^-2. Au NPs were partly observed in the SiO₂, probably due to the recoil implantation. Amorphous carbon (a-C) layer exhibits low sputtering loss even under 4 MeV C₆₀ irradiation. However, the elongation in a-C layer was low. While the ITO layer showed a certain decrease in thickness under 4 MeV C₆₀ irradiation, large elongation of Au NPs was observed under both 4 MeV C₆₀ and 200 MeV Xe irradiation. The ITO layer preserved the crystallinity even after large elongation was induced. This is the first report of the elongation of metal NPs in a crystalline matrix.

[Lupus anticoagulant-hypoprothrombinemia syndrome associated with follicular lymphoma]

A 56-year-old woman was referred to our hospital with symptoms of swelling, purpura, and pain in her limbs. Prior to referral, bleeding in her limbs had spontaneously appeared and disappeared several times. Prothrombin time (PT) and activated partial thromboplastin time (aPTT) were prolonged, and the factor II level was 17%. The plasma-mixing test indicated lupus anticoagulant (LA), which was confirmed using aPTT-LA and dilute Russell's viper venom time (dRVVT). Therefore, she was diagnosed with lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS). During screening for underlying disorders, chest computed tomography (CT) revealed a retrosternal mass. Biopsy was not performed because the administration of freshly frozen plasma failed to correct her coagulopathy. Prednisolone (PSL) treatment (1 mg/kg) was initiated, which normalized the coagulation tests. The retrosternal mass also disappeared. PSL was tapered without LAHPS recurrence; however, the follow-up CT revealed systemic lymphadenopathy. Follicular lymphoma was diagnosed using lymph-node biopsy. Considering the subsequent LAHPS recurrence, six cycles of bendamustine + rituximab were administered. Complete response with no LAHPS recurrence was observed at the time of drafting this report. LAHPS is rare and distinct from antiphospholipid syndrome because it can cause severe bleeding. Underlying disorders should be evaluated in cases of LAHPS.

SHAPE ESTIMATION OF BOWTIE FILTERS BASED ON THE LUMINESCENCE FROM POLYETHYLENE TEREPHTHALATE RESIN BY X-RAY IRRADIATION

In this study, we devised a novel method estimating the bowtie filter shapes by imaging luminescence from a polyethylene terephthalate (PET) resin with X-ray irradiation in a computed tomography (CT) scanner. The luminescence distribution of the PET resin corresponding to the thickness of bowtie filter was imaged using a charge-coupled device camera. On the assumption that the material of bowtie filter is aluminium (Al), the shape of bowtie filters was estimated from the correlation between Al attenuation curves and the angular-dependent luminance attenuation profiles according to the thickness of bowtie filters. Dose simulations based on the estimated bowtie filter shapes were performed using head and body PMMA phantoms with 16 and 32 cm in diameter. The simulated values of head and body weighted CT dose index (CTDIw) based on bowtie filter shape by the luminescence imaging method agreed within ~9% with the measured values by a dosemeter.