Displaying publications 21 - 40 of 45 in total

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  1. Kim SH, Seo J, Kwon SS, Teng LY, Won D, Shin S, et al.
    Epilepsia, 2024 Mar;65(3):766-778.
    PMID: 38073125 DOI: 10.1111/epi.17857
    OBJECTIVE: We aimed to identify common genes and recurrent causative variants in a large group of Asian patients with different epilepsy syndromes and subgroups.

    METHODS: Patients with unexplained pediatric-onset epilepsy were identified from the in-house Severance Neurodevelopmental Disorders and Epilepsy Database. All patients underwent either exome sequencing or multigene panels from January 2017 to December 2019, at Severance Children's Hospital in Korea. Clinical data were extracted from the medical records.

    RESULTS: Of the 957 patients studied, 947 (99.0%) were Korean and 570 were male (59.6%). The median age at testing was 4.91 years (interquartile range, 1.53-9.39). The overall diagnostic yield was 32.4% (310/957). Clinical exome sequencing yielded a diagnostic rate of 36.9% (134/363), whereas the epilepsy panel yielded a diagnostic rate of 29.9% (170/569). Diagnostic yield differed across epilepsy syndromes. It was high in Dravet syndrome (87.2%, 41/47) and early infantile developmental epileptic encephalopathy (60.7%, 17/28), but low in West syndrome (21.8%, 34/156) and myoclonic-atonic epilepsy (4.8%, 1/21). The most frequently implicated genes were SCN1A (n = 49), STXBP1 (n = 15), SCN2A (n = 14), KCNQ2 (n = 13), CDKL5 (n = 11), CHD2 (n = 9), SLC2A1 (n = 9), PCDH19 (n = 8), MECP2 (n = 6), SCN8A (n = 6), and PRRT2 (n = 5). The recurrent genetic abnormalities included 15q11.2 deletion/duplication (n = 9), Xq28 duplication (n = 5), PRRT2 deletion (n = 4), MECP2 duplication (n = 3), SCN1A, c.2556+3A>T (n = 3), and 2q24.3 deletion (n = 3).

    SIGNIFICANCE: Here we present the results of a large-scale study conducted in East Asia, where we identified several common genes and recurrent variants that varied depending on specific epilepsy syndromes. The overall genetic landscape of the Asian population aligns with findings from other populations of varying ethnicities.

  2. Sirohi R, Kumar Pandey A, Ranganathan P, Singh S, Udayan A, Kumar Awasthi M, et al.
    Bioresour Technol, 2022 Apr;349:126858.
    PMID: 35183729 DOI: 10.1016/j.biortech.2022.126858
    There has been increasing attention in recent years on the use of photobioreactors for various biotechnological applications, especially for the cultivation of microalgae. Photobioreactors-based production of photosynthetic microorganisms furnish several advantages as minimising toxicity and providing improved conditions. However, the designing and scaling-up of photobioreactors (PBRs) remain a challenge. Due to huge capital investment and operating cost, there is a deficiency of suitable PBRs for development of photosynthetic microorganisms on large-scale. It is, therefore, highly desirable to understand the current state-of-the-art PBRs, their advantages and limitations so as to classify different PBRs as per their most suited applications. This review provides a holistic overview of the discreet features of diverse PBR designs and their purpose in microalgae growth and biohydrogen production and also summarizes the recent development in use of hybrid PBRs to increase their working efficiency and overall economics of their operation for the production of value-added products.
  3. Khan JS, Piozzi GN, Rouanet P, Saklani A, Ozben V, Neary P, et al.
    Eur J Surg Oncol, 2024 Jun;50(6):108308.
    PMID: 38583214 DOI: 10.1016/j.ejso.2024.108308
    BACKGROUND: Around 20% of rectal tumors are locally advanced with invasion into adjacent structures at presentation. These may require surgical resections beyond boundaries of total mesorectal excision (bTME) for radicality. Robotic bTME is under investigation. This study reports perioperative and oncological outcomes of robotic bTME for locally advanced rectal cancers.

    MATERIALS AND METHODS: A multicentre, retrospective analysis of prospectively collected robotic bTME resections (July 2015-November 2020). Demographics, clinicopathological features, short-term outcomes, recurrences, and survival were investigated.

    RESULTS: One-hundred-sixty-eight patients (eight centres) were included. Median age and BMI were 60.0 (50.0-68.7) years and 24.0 (24.4-27.7) kg/m2. Female sex was prevalent (n = 95, 56.8%). Fifty patients (29.6%) were ASA III-IV. Neoadjuvant chemoradiotherapy was given to 125 (74.4%) patients. Median operative time was 314.0 (260.0-450.0) minutes. Median estimated blood loss was 150.0 (27.5-500.0) ml. Conversion to laparotomy was seen in 4.8%. Postoperative complications occurred in 77 (45.8%) patients; 27.3% and 3.9% were Clavien-Dindo III and IV, respectively. Thirty-day mortality was 1.2% (n = 2). R0 rate was 92.9%. Adjuvant chemotherapy was offered to 72 (42.9%) patients. Median follow-up was 34.0 (10.0-65.7) months. Distant and local recurrences were seen in 35 (20.8%) and 15 patients (8.9%), respectively. Overall survival (OS) at 1, 3, and 5-years was 91.7, 82.1, and 76.8%. Disease-free survival (DFS) at 1, 3, and 5-years was 84.0, 74.5, and 69.2%.

    CONCLUSION: Robotic bTME is technically safe with relatively low conversion rate, good OS, and acceptable DFS in the hands of experienced surgeons in high volume centres. In selected cases robotic approach allows for high R0 rates during bTME.

  4. Baek SJ, Lim H, Oh S, Lee S, Kim Y, Song JE, et al.
    Dis Colon Rectum, 2025 Mar 05.
    PMID: 40044408 DOI: 10.1097/DCR.0000000000003706
    BACKGROUND: Colorectal cancer is lacking non-invasive and efficient diagnostic markers. Recently, volatile organic compounds present in exhaled breath have emerged as potential diagnostic indicators for various diseases.

    OBJECTIVE: This study aimed to establish a predictive model including exhaled volatile organic compounds for the diagnosis of colorectal cancer.

    DESIGN: Prospective comparative study.

    SETTINGS: Single academic medical center.

    PATIENTS: Exhaled breath was collected prospectively from 112 colorectal cancer patients and 51 healthy controls. The exhaled breath of the research participants was collected under the control of various conditions, such as eating or smoking prior to collection.

    INTERVENTIONS: A total of 53 volatile organic compounds was analyzed in exhaled breath using thermal desorption-gas chromatography/mass spectrometry.

    MAIN OUTCOME MEASURES: After correcting various clinical variables that may affect volatile organic compound, the concentrations detected in the colorectal cancer group and the healthy control group were compared.

    RESULTS: Four predictive models were established using both matched clinical variables and volatile organic compound values to differentiate between colorectal cancer and healthy controls. In the four models, clinical variables of age, gender, room temperature, heating and cooling, fasting duration, intake of grilled meat or fish, and bowel preparation were included, along with levels of eight volatile organic compounds (ethanol, decanal, 1-iodononane, dodecane, hexanal, 1-nonene, (1S)-(-)-alpha-pinene, and acetophenone). The sensitivity of the four prediction models ranged from 84.0% to 98.2%, the specificity ranged from 89.2% to 93.8%, and the area under the receiver operating characteristic curve ranged from 92.1% to 98.3%.

    LIMITATIONS: The demographics of the participants in the groups were different.

    CONCLUSIONS: Eight types of volatile organic compounds in the exhaled breath of the colorectal cancer group were significantly different from those of the healthy control group. Our results support the diagnosis of colorectal cancer using a predictive model combining volatile organic compounds and specific clinical variables. See Video Abstract.

  5. Kim MJ, Bae IK, Jeong SH, Kim SH, Song JH, Choi JY, et al.
    J Antimicrob Chemother, 2013 Dec;68(12):2820-4.
    PMID: 23843299 DOI: 10.1093/jac/dkt269
    To investigate the epidemiological traits of metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa (MPPA) clinical isolates collected by the Asian Network for Surveillance of Resistant Pathogens (ANSORP).
  6. Baek JY, Kang CI, Kim SH, Ko KS, Chung DR, Peck KR, et al.
    Diagn Microbiol Infect Dis, 2016 Jun;85(2):218-20.
    PMID: 27083121 DOI: 10.1016/j.diagmicrobio.2016.02.022
    Tedizolid phosphate is a second-generation oxazolidinone prodrug that is potential activity against a wide range of Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus, penicillin-resistant streptococci, and vancomycin-resistant enterococci. The in vitro activity of tedizolid and other comparator agents against multidrug-resistant (MDR) pneumococci from various Asian countries were evaluated. Of the S. pneumoniae clinical pneumonia isolates collected during 2008 and 2009 from 8 Asian countries (Korea, Taiwan, Thailand, Hong Kong, Vietnam, Malaysia, Philippines, and Sri Lanka), 104 isolates of MDR pneumococci were included in this study. Antimicrobial susceptibility testing for 18 antimicrobial agents was performed by broth microdilution method. Tedizolid was highly active against pneumococci. All isolates tested were inhibited at a tedizolid minimum inhibitory concentration (MIC) value of ≤0.25μg/ml (ranged from ≤0.03μg/ml to 0.25μg/ml). The MIC50 and MIC90 of tedizolid against MDR pneumococci were both 0.12μg/ml, while MIC50 and MIC90 of linezolid were 0.5μg/ml and 1μg/ml, respectively. In addition, tedizolid maintained the activity against S. pneumoniae regardless of the extensively drug-resistant (XDR) phenotype of the isolates. The activity of tedizolid was excellent against all types of MDR pneumococci, exhibiting and maintaining at least 4-fold-greater potency compared to linezolid, regardless of resistance phenotypes to other commonly utilized agents. Tedizolid has the potential to be an agent to treat infections caused by MDR pneumococci in the Asia.
  7. Rasheed ZBM, Lee YS, Kim SH, Rai RK, Ruano CSM, Anucha E, et al.
    Front Immunol, 2020;11:1899.
    PMID: 32983111 DOI: 10.3389/fimmu.2020.01899
    Background: Infection/inflammation is an important causal factor in spontaneous preterm birth (sPTB). Most mechanistic studies have concentrated on the role of bacteria, with limited focus on the role of viruses in sPTB. Murine studies support a potential multi-pathogen aetiology in which a double or sequential hit of both viral and bacterial pathogens leads to a higher risk preterm labour. This study aimed to determine the effect of viral priming on bacterial induced inflammation in human in vitro models of ascending and haematogenous infection. Methods: Vaginal epithelial cells, and primary amnion epithelial cells and myocytes were used to represent cell targets of ascending infection while interactions between peripheral blood mononuclear cells (PBMCs) and placental explants were used to model systemic infection. To model the effect of viral priming upon the subsequent response to bacterial stimuli, each cell type was stimulated first with a TLR3 viral agonist, and then with either a TLR2 or TLR2/6 agonist, and responses compared to those of each agonist alone. Immunoblotting was used to detect cellular NF-κB, AP-1, and IRF-3 activation. Cellular TLR3, TLR2, and TLR6 mRNA was quantified by RT-qPCR. Immunoassays were used to measure supernatant cytokine, chemokine and PGE2 concentrations. Results: TLR3 ("viral") priming prior to TLR2/6 agonist ("bacterial") exposure augmented the pro-inflammatory, pro-labour response in VECs, AECs, myocytes and PBMCs when compared to the effects of agonists alone. In contrast, enhanced anti-inflammatory cytokine production (IL-10) was observed in placental explants. Culturing placental explants in conditioned media derived from PBMCs primed with a TLR3 agonist enhanced TLR2/6 agonist stimulated production of IL-6 and IL-8, suggesting a differential response by the placenta to systemic inflammation compared to direct infection as a result of haematogenous spread. TLR3 agonism generally caused increased mRNA expression of TLR3 and TLR2 but not TLR6. Conclusion: This study provides human in vitro evidence that viral infection may increase the susceptibility of women to bacterial-induced sPTB. Improved understanding of interactions between viral and bacterial components of the maternal microbiome and host immune response may offer new therapeutic options, such as antivirals for the prevention of PTB.
  8. Shahrizaila N, Sobue G, Kuwabara S, Kim SH, Birks C, Fan DS, et al.
    J Neurol Neurosurg Psychiatry, 2016 08;87(8):821-30.
    PMID: 27093948 DOI: 10.1136/jnnp-2015-312751
    While the past 2 decades have witnessed an increasing understanding of amyotrophic lateral sclerosis (ALS) arising from East Asia, particularly Japan, South Korea, Taiwan and China, knowledge of ALS throughout the whole of Asia remains limited. Asia represents >50% of the world population, making it host to the largest patient cohort of ALS. Furthermore, Asia represents a diverse population in terms of ethnic, social and cultural backgrounds. In this review, an overview is presented that covers what is currently known of ALS in Asia from basic epidemiology and genetic influences, through to disease characteristics including atypical phenotypes which manifest a predilection for Asians. With the recent establishment of the Pan-Asian Consortium for Treatment and Research in ALS to facilitate collaborations between clinicians and researchers across the region, it is anticipated that Asia and the Pacific will contribute to unravelling the uncertainties in ALS.
  9. Kim SH, Chung DR, Song JH, Baek JY, Thamlikitkul V, Wang H, et al.
    Vaccine, 2020 08 27;38(38):6065-6073.
    PMID: 31590932 DOI: 10.1016/j.vaccine.2019.09.065
    This study was performed to investigate the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae in Asian countries. A prospective surveillance study on S. pneumoniae collected from adult patients (≥50 years old) with invasive pneumococcal disease or community-acquired pneumonia was performed at 66 hospitals in Asian countries (Korea, China, Malaysia, Singapore, the Philippines, and Thailand) in 2012-2017. Serotyping and antimicrobial susceptibility tests of 850 pneumococcal isolates were performed. The proportions of isolates with serotypes covered by 13-valent pneumococcal conjugate vaccine (PCV13) were 37.0% in Korea, 53.4% in China, 77.2% in Malaysia, 35.9% in the Philippines, 68.7% in Singapore, and 60.2% in Thailand. Major serotypes were 19F (10.4%), 19A (10.1%), and 3 (8.5%) in 2012-2017, with different serotype distributions in each country. Macrolide resistance in pneumococci was high (66.8%) and prevalence of multidrug resistance (MDR) also remained high (50.8%). MDR non-PCV13 serotypes such as 11A, 15A, 35B, and 23A have emerged in Asian countries. This study showed the persistent prevalence of 19F and 19A with a noteworthy increase of certain non-PCV13 serotypes in Asian countries. High prevalence of macrolide resistance and MDR was also found in pneumococcal isolates. These data emphasize the need for continued surveillance of pneumococcal epidemiology in Asia in the post-pneumococcal vaccine era.
  10. Kim DH, Choi JY, Kim HW, Kim SH, Chung DR, Peck KR, et al.
    Antimicrob Agents Chemother, 2013 Nov;57(11):5239-46.
    PMID: 23939892 DOI: 10.1128/AAC.00633-13
    In this surveillance study, we identified the genotypes, carbapenem resistance determinants, and structural variations of AbaR-type resistance islands among carbapenem-resistant Acinetobacter baumannii (CRAB) isolates from nine Asian locales. Clonal complex 92 (CC92), corresponding to global clone 2 (GC2), was the most prevalent in most Asian locales (83/108 isolates; 76.9%). CC108, or GC1, was a predominant clone in India. OXA-23 oxacillinase was detected in CRAB isolates from most Asian locales except Taiwan. blaOXA-24 was found in CRAB isolates from Taiwan. AbaR4-type resistance islands, which were divided into six subtypes, were identified in most CRAB isolates investigated. Five isolates from India, Malaysia, Singapore, and Hong Kong contained AbaR3-type resistance islands. Of these, three isolates harbored both AbaR3- and AbaR4-type resistance islands simultaneously. In this study, GC2 was revealed as a prevalent clone in most Asian locales, with the AbaR4-type resistance island predominant, with diverse variants. The significance of this study lies in identifying the spread of global clones of carbapenem-resistant A. baumannii in Asia.
  11. Lee YH, Quek ST, Khong PL, Lee CS, Wu JS, Zhang L, et al.
    Br J Radiol, 2020 Sep;93(1113):20200082.
    PMID: 32584595 DOI: 10.1259/bjr.20200082
    OBJECTIVE: To understand the status of pre-procedural safety practices in radiological examinations at radiology residency training institutions in various Asian regions.

    METHODS: A questionnaire based on the Joint Commission International Accreditation Standards was electronically sent to 3 institutions each in 10 geographical regions across 9 Asian countries. Questions addressing 45 practices were divided into 3 categories. A five-tier scale with numerical scores was used to evaluate safety practices in each institution. Responses obtained from three institutions in the United States were used to validate the execution rate of each surveyed safety practice.

    RESULTS: The institutional response rate was 70.0% (7 Asian regions, 21 institutions). 44 practices (all those surveyed except for the application of wrist tags for identifying patients with fall risks) were validated using the US participants. Overall, the Asian participants reached a consensus on 89% of the safety practices. Comparatively, most Asian participants did not routinely perform three pre-procedural practices in the examination appropriateness topic.

    CONCLUSION: Based on the responses from 21 participating Asian institutions, most routinely perform standard practices during radiological examinations except when it comes to examination appropriateness. This study can provide direction for safety policymakers scrutinizing and improving regional standards of care.

    ADVANCES IN KNOWLEDGE: This is the first multicenter survey study to elucidate pre-procedural safety practices in radiological examinations in seven Asian regions.

  12. Kawarada O, Hozawa K, Zen K, Huang HL, Kim SH, Choi D, et al.
    Cardiovasc Interv Ther, 2020 Jan;35(1):52-61.
    PMID: 31292931 DOI: 10.1007/s12928-019-00602-z
    With technological improvements in the endovascular armamentarium, there have been tremendous advances in catheter-based femoropopliteal artery intervention during the last decade. However, standardization of the methodology for assessing outcomes has been underappreciated, and unvalidated peak systolic velocity ratios (PSVRs) of 2.0, 2.4, and 2.5 on duplex ultrasonography have been arbitrarily but routinely used for assessing restenosis. Quantitative vessel analysis (QVA) is a widely accepted method to identify restenosis in a broad spectrum of cardiovascular interventions, and PSVR needs to be validated by QVA. This multidisciplinary review is intended to disseminate the importance of QVA and a validated PSVR based on QVA for binary restenosis in contemporary femoropopliteal intervention.
  13. Kawarada O, Zen K, Hozawa K, Ayabe S, Huang HL, Choi D, et al.
    Cardiovasc Interv Ther, 2018 Oct;33(4):297-312.
    PMID: 29654408 DOI: 10.1007/s12928-018-0523-z
    The burden of peripheral artery disease (PAD) and diabetes in Asia is projected to increase. Asia also has the highest incidence and prevalence of end-stage renal disease (ESRD) in the world. Therefore, most Asian patients with PAD might have diabetic PAD or ESRD-related PAD. Given these pandemic conditions, critical limb ischemia (CLI) with diabetes or ESRD, the most advanced and challenging subset of PAD, is an emerging public health issue in Asian countries. Given that diabetic and ESRD-related CLI have complex pathophysiology that involve arterial insufficiency, bacterial infection, neuropathy, and foot deformity, a coordinated approach that involves endovascular therapy and wound care is vital. Recently, there is increasing interaction among cardiologists, vascular surgeons, radiologists, orthopedic surgeons, and plastic surgeons beyond specialty and country boundaries in Asia. This article is intended to share practical Asian multidisciplinary consensus statement on the collaboration between endovascular therapy and wound care for CLI.
  14. Piozzi GN, Khobragade K, Aliyev V, Asoglu O, Bianchi PP, Butiurca VO, et al.
    Colorectal Dis, 2023 Sep;25(9):1896-1909.
    PMID: 37563772 DOI: 10.1111/codi.16704
    AIM: Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future.

    METHOD: A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol.

    RESULTS: Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements.

    CONCLUSION: This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

  15. Fulsom BG, Pedlar TK, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Dec 07;121(23):232001.
    PMID: 30576207 DOI: 10.1103/PhysRevLett.121.232001
    We report the observation of ϒ(2S)→γη_{b}(1S) decay based on an analysis of the inclusive photon spectrum of 24.7  fb^{-1} of e^{+}e^{-} collisions at the ϒ(2S) center-of-mass energy collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure a branching fraction of B[ϒ(2S)→γη_{b}(1S)]=(6.1_{-0.7-0.6}^{+0.6+0.9})×10^{-4} and derive an η_{b}(1S) mass of 9394.8_{-3.1-2.7}^{+2.7+4.5}  MeV/c^{2}, where the uncertainties are statistical and systematic, respectively. The significance of our measurement is greater than 7 standard deviations, constituting the first observation of this decay mode.
  16. Li YB, Shen CP, Yuan CZ, Adachi I, Aihara H, Al Said S, et al.
    Phys Rev Lett, 2019 Mar 01;122(8):082001.
    PMID: 30932568 DOI: 10.1103/PhysRevLett.122.082001
    We present the first measurements of absolute branching fractions of Ξ_{c}^{0} decays into Ξ^{-}π^{+}, ΛK^{-}π^{+}, and pK^{-}K^{-}π^{+} final states. The measurements are made using a dataset comprising (772±11)×10^{6} BB[over ¯] pairs collected at the ϒ(4S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. We first measure the absolute branching fraction for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} using a missing-mass technique; the result is B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})=(9.51±2.10±0.88)×10^{-4}. We subsequently measure the product branching fractions B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→Ξ^{-}π^{+}), B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→ΛK^{-}π^{+}), and B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+}) with improved precision. Dividing these product branching fractions by the result for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} yields the following branching fractions: B(Ξ_{c}^{0}→Ξ^{-}π^{+})=(1.80±0.50±0.14)%, B(Ξ_{c}^{0}→ΛK^{-}π^{+})=(1.17±0.37±0.09)%, and B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+})=(0.58±0.23±0.05)%. For the above branching fractions, the first uncertainties are statistical and the second are systematic. Our result for B(Ξ_{c}^{0}→Ξ^{-}π^{+}) can be combined with Ξ_{c}^{0} branching fractions measured relative to Ξ_{c}^{0}→Ξ^{-}π^{+} to yield other absolute Ξ_{c}^{0} branching fractions.
  17. Seong IS, Vahsen SE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2019 Jan 11;122(1):011801.
    PMID: 31012694 DOI: 10.1103/PhysRevLett.122.011801
    We report on the first Belle search for a light CP-odd Higgs boson, A^{0}, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π^{+}π^{-}, followed by the on-shell process ϒ(1S)→γA^{0} with A^{0}→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×10^{6} ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges M_{A^{0}}<8.97  GeV/c^{2} and M_{χ}<4.44  GeV/c^{2}. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5  GeV/c^{2}.
  18. Sibidanov A, Varvell KE, Adachi I, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Jul 20;121(3):031801.
    PMID: 30085771 DOI: 10.1103/PhysRevLett.121.031801
    We report the results of a search for the rare, purely leptonic decay B^{-}→μ^{-}ν[over ¯]_{μ} performed with a 711  fb^{-1} data sample that contains 772×10^{6}  BB[over ¯] pairs, collected near the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B^{-}→μ^{-}ν[over ¯]_{μ})=(6.46±2.22±1.60)×10^{-7} or a frequentist 90% confidence level interval on the B^{-}→μ^{-}ν[over ¯]_{μ} branching fraction of [2.9,10.7]×10^{-7}.
  19. Guido E, Mussa R, Tamponi U, Aihara H, Al Said S, Asner DM, et al.
    Phys Rev Lett, 2018 Aug 10;121(6):062001.
    PMID: 30141661 DOI: 10.1103/PhysRevLett.121.062001
    We report the first observation of the hadronic transition ϒ(4S)→η^{'}ϒ(1S), using 496  fb^{-1} data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We reconstruct the η^{'} meson through its decays to ρ^{0}γ and to π^{+}π^{-}η, with η→γγ. We measure B(ϒ(4S)→η^{'}ϒ(1S))=[3.43±0.88(stat)±0.21(syst)]×10^{-5}, with a significance of 5.7σ.
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