Microstructural, Micromechanical Atlas of the Temporomandibular Joint Disc

The temporomandibular joint (TMJ) disc is mainly composed of collagen, with its arrangement responding to efficient stress distribution. However, microstructural and micromechanical transformations of the TMJ disc under resting, functional, and pathological conditions remain unclear. To address this, our study presents a high-resolution microstructural and mechanical atlas of the porcine TMJ disc. First, the naive microstructure and mechanical properties were investigated in porcine TMJ discs (resting and functional conditions). Subsequently, the perforation and tear models (pathological conditions) were compared. Following this, a rabbit model of anterior disc displacement (abnormal stress) was studied. Results show diverse microstructures and mechanical properties at the nanometer to micrometer scale. In the functional state, gradual unfolding of the crimping cycle in secondary and tertiary structures leads to D-cycle prolongation in the primary structure, causing tissue failure. Pathological conditions lead to stress concentration near the injury site due to collagen interfibrillar traffic patterns, resulting in earlier damage manifestation. Additionally, the abnormal stress model shows collagen damage initiating at the primary structure and extending to the superstructure over time. These findings highlight collagen's various roles in different pathophysiological states. Our study offers valuable insights into TMJ disc function and dysfunction, aiding the development of diagnostic and therapeutic strategies for TMJ disorders, as well as providing guidance for the design of structural biomimetic materials.

How comparable are patient outcomes in the "real-world" with populations studied in pivotal AML trials?

Despite an increasing desire to use historical cohorts as "synthetic" controls for new drug evaluation, limited data exist regarding the comparability of real-world outcomes to those in clinical trials. Governmental cancer data often lacks details on treatment, response, and molecular characterization of disease sub-groups. The Australasian Leukaemia and Lymphoma Group National Blood Cancer Registry (ALLG NBCR) includes source information on morphology, cytogenetics, flow cytometry, and molecular features linked to treatment received (including transplantation), response to treatment, relapse, and survival outcome. Using data from 942 AML patients enrolled between 2012-2018, we assessed age and disease-matched control and interventional populations from published randomized trials that led to the registration of midostaurin, gemtuzumab ozogamicin, CPX-351, oral azacitidine, and venetoclax. Our analyses highlight important differences in real-world outcomes compared to clinical trial populations, including variations in anthracycline type, cytarabine intensity and scheduling during consolidation, and the frequency of allogeneic hematopoietic cell transplantation in first remission. Although real-world outcomes were comparable to some published studies, notable differences were apparent in others. If historical datasets were used to assess the impact of novel therapies, this work underscores the need to assess diverse datasets to enable geographic differences in treatment outcomes to be accounted for.

Multicentre study of hospitalised patients with sports- and recreational cycling-related traumatic brain injury in Hong Kong

INTRODUCTION

Cycling is associated with a greater risk of traumatic brain injury (TBI) than other recreational activities. This study aimed to investigate the epidemiology of sports-related TBI in Hong Kong and to examine predictors for recreational cycling-induced intracranial haemorrhage.

METHODS

This retrospective multicentre study included patients diagnosed with sports-related TBI in public hospitals in Hong Kong from 2015 to 2019. Computed tomography scans were reviewed by an independent assessor. The primary endpoint was traumatic intracranial haemorrhage. The secondary endpoint was an unfavourable Glasgow Outcome Scale (GOS) score at discharge from hospital.

RESULTS

In total, 720 patients were hospitalised with sports-related TBI. The most common sport was cycling (59.2%). The crude incidence of cycling-related TBI was 1.1 per 100 000 population. Cyclists were more likely to exhibit intracranial haemorrhage and an unfavourable GOS score, compared with patients who had TBI because of other sports. Although 47% of cyclists had intracranial haemorrhage, only 15% wore a helmet. In multivariate analysis, significant predictors for intracranial haemorrhage were age ≥60 years, antiplatelet medication, moderate or severe TBI, and skull fracture. Among 426 cyclists, 375 (88%) had mild TBI, and helmet wearing was protective against intracranial haemorrhage, regardless of age, antiplatelet medication intake, and mechanism of injury. Of 426 cyclists, 31 (7.3%) had unfavourable outcomes on discharge from hospital.

CONCLUSIONS

The incidence of sports-related TBI is low in Hong Kong. Although cycling-related head injuries carried greater risks of intracranial haemorrhage and unfavourable outcomes compared with other sports, most cyclists experienced good recovery. Helmet wearing among recreational cyclists with mild TBI was protective against intracranial haemorrhage and skull fracture.

Inconsistent idealizations and inferentialism about scientific representation

Inferentialists about scientific representation hold that an apparatus's representing a target system consists in the apparatus allowing "surrogative inferences" about the target. I argue that a serious problem for inferentialism arises from the fact that many scientific theories and models contain internal inconsistencies. Inferentialism, left unamended, implies that inconsistent scientific models have unlimited representational power, since an inconsistency permits any conclusion to be inferred. I consider a number of ways that inferentialists can respond to this challenge before suggesting my own solution. I develop an analogy to exploitable glitches in a game. Even though inconsistent representational apparatuses may in some sense allow for contradictions to be generated within them, doing so violates the intended function of the apparatus's parts and hence violates representational "gameplay".

[Research progress of hepatic non-parenchymal cells in nonalcoholic steatohepatitis]

Non-alcoholic steatohepatitis (NASH) is an important link for the progression of metabolic-related fatty liver disease to end-stage liver disease such as cirrhosis and hepatocellular carcinoma, which seriously endangers human health. NASH pathogenesis is complex, and involves the interaction between hepatic parenchymal and non-parenchymal cells (NPCs), sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, and so on. Herein, the relevant research progress of NPCs in the pathogenesis of NASH is reviewed in order to further understand the role of NPCs in NASH.

57 The Use of a Hemi Glabella Flap for Reconstruction of Medial Canthus Defects

Background

Medial canthal reconstruction is a challenging task due to the complex anatomy. The glabellar flap is a common viable technique; however, this results in narrowing of the eyebrows, bulky nasal dorsum and horizontal scarring which is aesthetically displeasing. The senior author in this paper has developed an intuitive modification to the technique.

Method

A rotational advancement flap involving the upper lateral nasal wall with the hemi glabella was formed and transferred to the medial canthal defect. The donor site was closed in a V-Y manner. Complete closure of defect was achieved in all patients.

Results

Reconstruction using the Hemi-Glabellar technique was performed on 12 patients following resection of BCC in or near the medial canthus area. Superficial cellulitis was noted in 2 patients, they were managed oral antibiotics. There was bruising in 7 patient which resolve spontaneously in 4-7 days. All patients had a good outcome at 2 months and 6 months follow up. There was no flap loss and all patients were satisfied with the aesthetic outcome.

Conclusions

The technique highlighted can be performed easily and is applicable to reconstruction to defects of the medial canthus with excellent aesthetic outcomes with an inconspicuous scar and supple skin with matching colour

59 Should The ‘Normal’ And ‘Ideal’ Nipple Position in A Male Influence the Surgeon When Planning Severe Gynaecomastia Correction?

Background

The ideal nipple position of the male chest following gynecomastia surgery is well documented however with increased development of the chest muscles, the NAC placement can change, leading to the medial displacement of the nipple giving a poor aesthetic outcome. Therefore, we feel these measurements need to be applied to the patients build and take into consideration the patient's future fitness goals.

Method

We have analysed photographs of 3 groups of men: super- athletes, athletes and severe gynaecomastia. We assessed the proportions of the chest in relation to the NAC and the degree of ptosis.

Results

There is wide variation in the position of the nipple to the chest wall between each group with minor variation within each group. Based on this research we believe that surgeons should be circumspect when considering breast reduction with a Wise pattern in patients with severe gynaecomastia.

In patient with increased development of the pectoralis major muscles, the NAC placement can change, leading to medial displacement of the nipple and ptosis and poor aesthetic result.

Conclusions

We suggest a two-stage procedure, carried out on two separate occasions wound be more ideal than a single stage as this allows better long-term better positioning of the nipple.

[Application analysis of noninvasive prenatal testing for fetal chromosome copy number variations in Chinese laboratories]

Objective: To investigate the general situation, detection range, testing reagents, and clinical performance of non-invasive prenatal testing (NIPT) for fetal chromosomal copy number variations (CNVs) in Chinese laboratories. Methods: The National Center for Clinical Laboratories of the National Health Commission designed a questionnaire for the detection of CNVs by NIPT, which included the investigation of whether the laboratory has carried out NIPT to detect CNVs and its testing scope, reagents/platforms, intended uses, screening populations and clinical performance. The questionnaires were distributed to 355 laboratories in 31 provinces, autonomous regions, and municipalities across the country on October, 2020. Further, the feedbacks were statistical analyzed. Results: Two hundred and twenty-eight laboratories had performed NIPT to detect CNVs, including 116 types of CNVs, and more than 95% of laboratories chose to detect the CNVs of 5p15 deletion, 22q11.2 deletion, 1p36 deletion, and 15q11.2 deletion. All testing reagents used were laboratory-developed tests and were based on massive parallel sequencing, the minimum amount of sequencing data was 3-15 M reads, the detection limit of fetal fraction was 3%-5%, and the minimum size of variants that can be detected was 1-5 Mb. The proportion of laboratories that apply CNVs testing for daily project, voluntary requirements of patients, and scientific research were 58.8% (134/228), 57.5% (131/228), and 20.6% (47/228), respectively. One hundred and thirty-four laboratories were fully or partially aware of the clinical performance of NIPT to detect microdeletion/microduplication syndromes, and the laboratories' declared sensitivity of NIPT for Cri du Chat syndrome, 22q11.2 deletion syndrome, 1p36 deletion syndrome, and Angelman syndrome were 50.0%-100%, 60.0%-100%, 50.0%-100%, and 33.3%-100%, and the positive predictive values were 9.0%-50.0%, 18.0%-100%, 20.0%-30.0%, and 20.0%. Conclusion: The detection of CNVs by NIPT in Chinese laboratories need to be standardized. Laboratories should detect CNVs with clear clinical significance in accordance with the guidelines, conduct performance validation of the reagents, then perform NIPT test and provide adequate interpretation after mastering the clinical performance sufficiently.

[A novel compound heterozygous mutation in MYSM1 gene in a 1-month-old girl: a bone marrow failure syndrome 4 family survey and literature review]

目的

报道1例MYSM1基因复合杂合变异致骨髓衰竭综合征4型患儿临床表现及全外显子检测结果，同时报道其家系全外显子检测结果，为早期诊断此类骨髓衰竭综合征提供典型案例。

方法

报道1例1月龄骨髓衰竭综合征4型患儿临床诊断过程，并对患儿及其家系成员外周血DNA进行全外显子测序，使用BWA、GATK等软件对测序结果进行注释分析。

结果

本例1月龄骨髓衰竭综合征4型患儿，表现为全血细胞减少、多指畸形，影像学示非特异性脑白质改变及囊肿，淋巴细胞亚群分类示CD3⁻CD19⁺ B细胞降低。通过家系全外显子测序检测，鉴定患儿携带分别遗传自父母的MYSM1基因复合杂合性变异NM_001085487.2:c.1607_c.1611delAAGAG和c.1432C>T。家系验证证实先证者父亲携带的c.1432C>T突变来源于先证者祖父，先证者母亲携带的c.1607_c.1611delAAGAG突变来自于先证者外祖父，其他家系成员均不携带突变。

结论

本研究新发现MYSM1致病性变异c.1607_c.1611delAAGAG，国内外尚未见报道。本例为BMFS4的早期诊断提供了典型案例，并扩展了MYSM1基因致病性变异谱和表型谱。

A74 INCREASING RATES OF CT IMAGING IN THE EMERGENCY DEPARTMENT AMONG PATIENTS WITH INFLAMMATORY BOWEL DISEASE

Background

Computed tomography (CT) imaging of the abdomen is often performed in the emergency department (ED) to exclude urgent pathology in patients with Inflammatory Bowel Disease (IBD). However, concerns over excessive radiation exposure from repeated use have led to expert consensus guidelines advising against CT imaging unless there is suspicion of complications (obstruction, perforation, abscess) or a non-IBD cause for symptoms.

Aims

Our study aimed to determine trends in abdominal CT utilization and findings among patients with IBD in the ED.

Methods

We performed a retrospective cohort study between 01/01/2009 and 31/12/2018 at a single academic center. We identified ED encounters for adults (age ≥17 years) with a pre-existing diagnosis of IBD from our institutional database and determined the proportion resulting in an abdominal CT scan within 72 hours of presentation. IBD subtypes were classified based on ICD-10 claims: K50.90* for Crohn’s disease (CD), K51.90* for Ulcerative colitis (UC) and IBD undifferentiated (IBDU) for patients with both claims. A time trend analysis was performed using a generalized linear model that assumed a Poisson distribution. CT scans were classified according to the dominant imaging finding. For this part we excluded studies performed within 1-month of surgery or those re-assessing a known abscess or malignancy.

Results

A total of 14783 encounters were identified. Among these encounters 3000 CT scans were performed: 2000 for patients with CD (21.9%), 652 for UC (16.5%) and 348 for IBDU (20.4%). The rates of CT utilization significantly increased by 2.7% (95% CI, 1.2–4.3; p=0.0004) in patients with CD, by 4.2% (95% CI, 1.7–6.7; p=0.0009) in patients with UC and by 6.3% in patients with IBDU (95% CI, 2.5–10.0; p=0.0011). Among the eligible CT scans performed for CD, the following dominant findings were reported: normal (25%), inflammation (23%), obstruction (23%), penetrating (18%) and unrelated to IBD (8.6%). In contrast, the following findings for patients with UC were reported: normal (20%), inflammation (39%), obstructive (19%), penetrating (8%) and unrelated to IBD (15%).

Conclusions

In this single center study, a steady increase in CT utilization in the ED was observed in patients with IBD. Interestingly, only a small proportion of the CT scans demonstrated urgent findings. Future studies are required to determine the factors that contribute to the ongoing increase in CT utilization in this patient population.

Funding Agencies

None

A222 ASSOCIATION BETWEEN PROTON PUMP INHIBITOR USE AND DEVELOPMENT OF HEPATIC ENCEPHALOPATHY AND SPONTANEOUS BACTERIAL PERITONITIS IN HOSPITALIZED PATIENTS WITH CIRRHOSIS

Background

Proton pump inhibitors (PPIs) are commonly prescribed medications which are indicated in various different gastrointestinal (GI) diseases, including peptic ulcer disease, gastroesophageal reflux disorder and upper GI bleeding. There is some evidence to suggest that PPI use in cirrhosis may predispose to the development of hepatic encephalopathy (HE) and spontaneous bacterial peritonitis (SBP), albeit with some controversy.

Aims

We aim to conduct a retrospective epidemiological analysis of the association between PPI use in hospitalized patients with cirrhosis and prevalence of HE and SBP.

Methods

This was a retrospective cohort study of 953 adult patients (mean age 62.3 (SD=12.2)) with cirrhosis admitted to the Ottawa Hospital between January 1, 2011 and December 31, 2015. A chart review was conducted and relevant information extracted.

Results

Average MELD-Na on admission was 17.4 (SD = 7.5) with no significant differences when stratified by in-hospital PPI use (p=0.53). 14.7% of patients had a prior history of HE, 5.4% SBP, 31.6% ascites, 9.3% hepatocellular carcinoma and 1.2% hepatorenal syndrome. 26.4% of patients had a history of varices, of which 34.4% had previous variceal bleeding. 45.4% of patients were on a PPI prior to admission and 69.8% during their hospitalization. Patients with a previous history of HE (16.8% vs. 9.6% p=0.006), varices (31.4% vs. 14.2% p<0.001) and variceal bleed (11.6% vs. 3.1% p<0.001) were more likely to be exposed to a PPI in-hospital. Mortality rate during index admission was 19.4%.

There was no significant association noted between the incidence of HE (31.2% vs. 25.0% p=0.06) or SBP (10.4% vs. 8.0% p=0.25) and in-hospital PPI use. There was also no significant association between PPI use and infectious complications, including bacteremia (8.6% vs. 7.6% p=0.63), pneumonia (12.7% vs. 12.5% p=0.95), urinary tract infections (9.2% vs. 6.6% p=0.19) and clostridium difficile (3.8% vs. 2.1% p=0.18). Patients on a PPI had greater in-hospital mortality (22.0% vs. 13. 5% p=0.002), although there was no significance between cause of death (p=0.31) nor death from infectious complications (18.5% vs. 23.1% p=0.52) between groups. Length of stay (LOS) was longer in patients exposed to PPI (median (IQR) 7 (4–17) vs 6 (3–13) p=0.03). Similar findings were noted on subgroup analysis of decompensated patients.

Conclusions

We did not observe a significant difference in HE, SBP or infectious complications among this cohort of cirrhotic patients by in-hospital PPI use. However, there was a significantly higher mortality rate noted in hospital and longer LOS, despite similar baseline MELD-Na and causes of death. Further study and judicious PPI prescribing practices in this vulnerable population of patients is warranted.

Funding Agencies

None

Quantum circuits with many photons on a programmable nanophotonic chip

Growing interest in quantum computing for practical applications has led to a surge in the availability of programmable machines for executing quantum algorithms1,2. Present-day photonic quantum computers3-7 have been limited either to non-deterministic operation, low photon numbers and rates, or fixed random gate sequences. Here we introduce a full-stack hardware-software system for executing many-photon quantum circuit operations using integrated nanophotonics: a programmable chip, operating at room temperature and interfaced with a fully automated control system. The system enables remote users to execute quantum algorithms that require up to eight modes of strongly squeezed vacuum initialized as two-mode squeezed states in single temporal modes, a fully general and programmable four-mode interferometer, and photon number-resolving readout on all outputs. Detection of multi-photon events with photon numbers and rates exceeding any previous programmable quantum optical demonstration is made possible by strong squeezing and high sampling rates. We verify the non-classicality of the device output, and use the platform to carry out proof-of-principle demonstrations of three quantum algorithms: Gaussian boson sampling, molecular vibronic spectra and graph similarity8. These demonstrations validate the platform as a launchpad for scaling photonic technologies for quantum information processing.

Measurement of single-diffractive dijet production in proton-proton collisions at s = 8 Te with the CMS and TOTEM experiments

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processesp p → p X andp p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, whereX includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton-proton collisions ats = 8 Te during a dedicated run withβ ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 ,0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentump T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.

Measurement of single-diffractive dijet production in proton-proton collisions at s = 8 Te with the CMS and TOTEM experiments

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processes p p → p X and p p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, where X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton-proton collisions at s = 8 Te during a dedicated run with β ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 , 0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentum p T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.

Mutant Isocitrate Dehydrogenase 1 Inhibitor Ivosidenib in Combination With Azacitidine for Newly Diagnosed Acute Myeloid Leukemia

PURPOSE

Ivosidenib is an oral inhibitor of the mutant isocitrate dehydrogenase 1 (IDH1) enzyme, approved for treatment of IDH1-mutant (mIDH1) acute myeloid leukemia (AML). Preclinical work suggested that addition of azacitidine to ivosidenib enhances mIDH1 inhibition-related differentiation and apoptosis.

PATIENTS AND METHODS

This was an open-label, multicenter, phase Ib trial comprising dose-finding and expansion stages to evaluate safety and efficacy of combining oral ivosidenib 500 mg once daily continuously with subcutaneous azacitidine 75 mg/m² on days 1-7 in 28-day cycles in patients with newly diagnosed mIDH1 AML ineligible for intensive induction chemotherapy (ClinicalTrials.gov identifier: NCT02677922).

RESULTS

Twenty-three patients received ivosidenib plus azacitidine (median age, 76 years; range, 61-88 years). Treatment-related grade ≥ 3 adverse events occurring in > 10% of patients were neutropenia (22%), anemia (13%), thrombocytopenia (13%), and electrocardiogram QT prolongation (13%). Adverse events of special interest included all-grade IDH differentiation syndrome (17%), all-grade electrocardiogram QT prolongation (26%), and grade ≥ 3 leukocytosis (9%). Median treatment duration was 15.1 months (range, 0.3-32.2 months); 10 patients remained on treatment as of February 19, 2019. The overall response rate was 78.3% (18/23 patients; 95% CI, 56.3% to 92.5%), and the complete remission rate was 60.9% (14/23 patients; 95% CI, 38.5% to 80.3%). With median follow-up of 16 months, median duration of response in responders had not been reached. The 12-month survival estimate was 82.0% (95% CI, 58.8% to 92.8%). mIDH1 clearance in bone marrow mononuclear cells by BEAMing (beads, emulsion, amplification, magnetics) digital polymerase chain reaction was seen in 10/14 patients (71.4%) achieving complete remission.

CONCLUSION

Ivosidenib plus azacitidine was well tolerated, with an expected safety profile consistent with monotherapy with each agent. Responses were deep and durable, with most complete responders achieving mIDH1 mutation clearance.

Peri-orbital surgical emphysema following endoscopic dacryocystorhinostomy

BACKGROUND

Peri-orbital surgical emphysema is a rare complication that can occur after lacrimal surgery. It has only been described in isolated cases, following external dacryocystorhinostomy (n = 2) and Lester Jones tube insertion (n = 1).

METHOD

A retrospective, non-comparative case series was conducted of patients who developed surgical emphysema following endoscopic dacryocystorhinostomy.

RESULTS

A total of 356 endoscopic dacryocystorhinostomy cases (primary, n = 316; revision, n = 40) were performed over a six-year period. Seven cases of post-operative surgical emphysema were identified, all of which were preceded by uncontrolled sneezing, nose-blowing or coughing within the first week of surgery. The occurrence of surgical emphysema post-endoscopic dacryocystorhinostomy in our centre was 7 in 356, or 2 per cent, over six years.

CONCLUSION

This is the first study to report the occurrence of surgical emphysema post-endoscopic dacryocystorhinostomy. Clinicians may wish to suggest patients stifle the aforementioned triggers within the first week to reduce the potential for surgical emphysema.

Studies of Charm Quark Diffusion inside Jets Using Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV

The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4<p_{T}^{D}<20  GeV/c hints at a larger distance on average with respect to the jet axis, reflecting a diffusion of charm quarks in the medium created in heavy ion collisions. At higher p_{T}^{D}, the Pb-Pb and pp radial distributions are found to be similar.

Study of central exclusive production in proton-proton collisions at s = 5.02 and 13TeV

Central exclusive and semiexclusive production of pairs is measured with the CMS detector in proton-proton collisions at the LHC at center-of-mass energies of 5.02 and 13TeV. The theoretical description of these nonperturbative processes, which have not yet been measured in detail at the LHC, poses a significant challenge to models. The two pions are measured and identified in the CMS silicon tracker based on specific energy loss, whereas the absence of other particles is ensured by calorimeter information. The total and differential cross sections of exclusive and semiexclusive central production are measured as functions of invariant mass, transverse momentum, and rapidity of the system in the fiducial region defined as transverse momentum and pseudorapidity . The production cross sections for the four resonant channels , , , and are extracted using a simple model. These results represent the first measurement of this process at the LHC collision energies of 5.02 and 13TeV.

Mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles in PbPb collisions at s NN = 2.76 and 5.02 TeV

Anisotropies in the initial energy density distribution of the quark-gluon plasma created in high energy heavy ion collisions lead to anisotropies in the azimuthal distributions of the final-state particles known as collective anisotropic flow. Fourier harmonic decomposition is used to quantify these anisotropies. The higher-order harmonics can be induced by the same order anisotropies (linear response) or by the combined influence of several lower order anisotropies (nonlinear response) in the initial state. The mixed higher-order anisotropic flow and nonlinear response coefficients of charged particles are measured as functions of transverse momentum and centrality in PbPb collisions at nucleon-nucleon center-of-mass energies s NN = 2.76 and 5.02 TeV with the CMS detector. The results are compared with viscous hydrodynamic calculations using several different initial conditions, as well as microscopic transport model calculations. None of the models provides a simultaneous description of the mixed higher-order flow harmonics and nonlinear response coefficients.

0997 The Sleep Disturbance Scale For Children In Youth With Tourette’S Disorder

Introduction

Sleep disturbance is common in youth with Persistent Tic Disorders (PTDs), including Tourette’s Disorder. However, studies elucidating the nature of sleep problems in PTDs are limited. The present study examines the types of sleep disturbance present in youth with PTDs relative to healthy controls, and investigates the relationship between sleep disturbance and tic severity.

Methods

Participants were 56 youth ages 8 to 17 (M=11.9, SD=2.86), including individuals with PTDs (n=27), and healthy controls (n=29). An interviewer evaluated psychiatric diagnosis using the Anxiety Disorders Interview Schedule, and tic severity using the Yale Global Tic Severity Scale (YGTSS). Parents rated sleep using the Sleep Disturbance Scale for Children (SDSC), and tic severity using the Parent Tic Questionnaire (PTQ). Independent-samples t-tests and bivariate correlations were performed.

Results

Higher SDSC Total scores, t(30)=-3.74, p=.001) were found in youth with PTDs relative to healthy controls. Youth with PTDs endorsed elevated sleep disturbance with respect to: Disorders of Initiating and Maintaining Sleep, t(35)=-2.43, p=.02), Sleep-Wake Transition Disorders, t(37)=-3.04, p=.004), and Disorders of Excessive Somnolence, t(33)=-2.36, p=.02). No significant group differenceswere shown for Sleep Breathing Disorders, Disorders of Arousal, and Sleep Hyperhydrosis. There was a positive association between SDSC Total scores and YGTSS Total (p=.01, r=.56) and YGTSS Impairment scores (p= .03, r=.33). Finally, there was a positive relationship between SDSC Total and PTQ Total scores (p=.01, r=.61).

Conclusion

Findings suggest youth with PTDs are more likely to experience sleep disturbance than healthy children, particularly difficulties with sleep initiation and maintenance, abnormal movements during sleep, and daytime sleepiness. Further, there is a relationship between sleep disturbance and tic severity. Findings highlight the need for sleep screening and targeted sleep intervention in youth with PTDs.

Support

N/A

Measurement of differential cross sections and charge ratios for t-channel single top quark production in proton-proton collisions at s = 13 Te

A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13Te by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9fb - 1 , events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum ( p T ), rapidity, and polarisation angle, the charged lepton p T and rapidity, and the p T of the W  boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and W  boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be 0.440 ± 0.070 , in agreement with the standard model prediction.

Epigenomic promoter alterations predict for benefit from immune checkpoint inhibition in metastatic gastric cancer

BACKGROUND

Utilization of alternative transcription start sites through alterations in epigenetic promoter regions causes reduced expression of immunogenic N-terminal peptides, which may facilitate immune evasion in early gastric cancer. We hypothesized that tumors with high alternate promoter utilization would be resistant to immune checkpoint inhibition in metastatic gastric cancer.

PATIENTS AND METHODS

Two cohorts of patients with metastatic gastric cancer treated with immunotherapy were analyzed. The first cohort (N = 24) included patients treated with either nivolumab or pembrolizumab. Alternate promoter utilization was measured using the NanoString® (NanoString Technologies, Seattle, WA, USA) platform on archival tissue samples. The second cohort was a phase II clinical trial of patients uniformly treated with pembrolizumab (N = 37). Fresh tumor biopsies were obtained, and transcriptomic analysis was carried out on RNAseq data. Alternate promoter utilization was correlated to T-cell cytolytic activity, objective response rate and survival.

RESULTS

In the first cohort 8 of 24 (33%) tumors were identified to have high alternate promoter utilization (APhigh), and this was used to define the APhigh tertile of the second cohort (13 APhigh of 37). APhigh tumors exhibited decreased markers of T-cell cytolytic activity and lower response rates (8% versus 42%, P = 0.03). Median progression-free survival was lower in the APhigh group (55 versus 180 days, P = 0.0076). In multivariate analysis, alternative promoter utilization was an independent predictor of immunotherapy survival [hazard ratio 0.29, 95% confidence interval 0.099-0.85, P = 0.024). Analyzing tumoral evolution through paired pre-treatment and post-treatment biopsies, we observed consistent shifts in alternative promoter utilization rate associated with clinical response.

CONCLUSION

A substantial proportion of metastatic gastric cancers utilize alternate promoters as a mechanism of immune evasion, and these tumors may be resistant to anti-PD1 immune checkpoint inhibition. Alternate promoter utilization is thus a potential mechanism of resistance to immune checkpoint inhibition, and a novel predictive biomarker for immunotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT#02589496.

A multi-dimensional search for new heavy resonances decaying to boosted W W , W Z , or Z Z boson pairs in the dijet final state at 13 Te

A search in an all-jet final state for new massive resonances decaying to W W , W Z , or Z Z boson pairs using a novel analysis method is presented. The analysis is performed on data corresponding to an integrated luminosity of 77.3 fb - 1 recorded with the CMS experiment at the LHC at a centre-of-mass energy of 13  Te . The search is focussed on potential narrow-width resonances with masses above 1.2  Te , where the decay products of each W or Z boson are expected to be collimated into a single, large-radius jet. The signal is extracted using a three-dimensional maximum likelihood fit of the two jet masses and the dijet invariant mass, yielding an improvement in sensitivity of up to 30% relative to previous search methods. No excess is observed above the estimated standard model background. In a heavy vector triplet model, spin-1 Z ' and W ' resonances with masses below 3.5 and 3.8   Te , respectively, are excluded at 95% confidence level. In a bulk graviton model, upper limits on cross sections are set between 27 and 0.2 fb for resonance masses between 1.2 and 5.2   Te , respectively. The limits presented in this paper are the best to date in the dijet final state.

Search for direct pair production of supersymmetric partners to the τ lepton in proton-proton collisions at s = 13 TeV

A search is presented for τ slepton pairs produced in proton-proton collisions at a center-of-mass energy of 13TeV . The search is carried out in events containing two τ leptons in the final state, on the assumption that each τ slepton decays primarily to a τ lepton and a neutralino. Events are considered in which each τ lepton decays to one or more hadrons and a neutrino, or in which one of the τ leptons decays instead to an electron or a muon and two neutrinos. The data, collected with the CMS detector in 2016 and 2017, correspond to an integrated luminosity of 77.2fb - 1 . The observed data are consistent with the standard model background expectation. The results are used to set 95% confidence level upper limits on the cross section for τ slepton pair production in various models for τ slepton masses between 90 and 200GeV and neutralino masses of 1, 10, and 20GeV . In the case of purely left-handed τ slepton production and decay to a τ lepton and a neutralino with a mass of 1GeV , the strongest limit is obtained for a τ slepton mass of 125GeV at a factor of 1.14 larger than the theoretical cross section.

A70 ASSOCIATION BETWEEN PROTON PUMP INHIBITOR USE IN HOSPITALIZED CIRRHOTICS AND DEVELOPMENT OF HEPATIC ENCEPHALOPATHY AND SPONTANEOUS BACTERIAL PERITONITIS

Background

Proton pump inhibitors (PPI) are commonly prescribed medications which are indicated in various different gastrointestinal (GI) diseases, including peptic ulcer disease, gastroesophageal reflux disorder and upper GI bleeding. There is some evidence to suggest that PPI use in cirrhosis may predispose to the development of hepatic encephalopathy (HE) and spontaneous bacterial peritonitis (SBP), albeit with some controversy.

Aims

We aim to conduct a retrospective epidemiological analysis of the association between PPI use in hospitalized patients with cirrhosis, and prevalence of HE and SBP.

Methods

This was a retrospective cohort study of 600 adult patients (mean age 61.4 (SD=12.2)) admitted the Ottawa Hospital between January 1, 2011 and December 31, 2015 with cirrhosis. A chart review was conducted and relevant information extracted.

Results

Average MELD-Na on admission was 16.2 (sd=6.7). 14.8% of patients had a history of HE, 5.0% SBP, 7.8% with history of hepatocellular carcinoma and 1.0% with history of hepatorenal syndrome. 28.5% of patients had a history of varices, of which 11.0% had previous variceal bleeding. 69.3% of patients were on a PPI during their hospitalization. Not surprisingly, patients admitted with variceal bleeding were more likely to be exposed to PPI in hospital (97.2% vs 63.2%, p&lt;0.01) Patients with a diagnosis of cirrhosis prior to index admission were more likely to be on a PPI in hospital (p=0.001) and on discharge (p=0.001). Patients with ascites were less likely to be on a PPI than those without ascites (64.1% vs 77.6%, p&lt;0.01). There was no significant correlation between in hospital PPI use and MELD score (p=0.42). Amongst patients on PPI in hospital, 85.9% remained on a PPI at discharge. Although numerically greater, no statistically significant differences were observed in terms of prevalence of HE (21.3% in patients on PPI vs 8.3% in those not on PPI (p=0.37)), nor SBP (5.7% on PPI vs. 3.7% in those not on PPI (p=0.29)).

Conclusions

We did not observe a significant difference in HE and SBP among this cohort of cirrhotic patients by in-hospital PPI use. We did however note significantly higher PPI use in patients with previous diagnosis of cirrhosis as compared to those who were newly diagnosed, as well as those whose admissions were related to bleeding. Patients with ascites had lower prevalence of PPI use. Prescribing patterns for PPIs in patients with cirrhosis warrant further attention, including clinical utility and longer-term risks and benefits of this therapy.

Funding Agencies

None

A158 LACK OF DIFFERENCE OF COLONIC CURVATURE IN SUPINE VERSUS PRONE PATIENT POSITIONS, IN NORMAL AND HIGH BMI INDIVIDUALS, AS ASSESSED BY QUANTITATIVE ASSESSMENT OF COMPUTED TOMOGRAPHY COLONOGRAPHY

Background

Dynamic positional changes during colonoscopy are commonly used in clinical practice, in particular moving from side to side. It has been shown to improve both adenoma detection rates as well as cecal intubation times. However, perhaps due to an additional level of inconvenience, there have been few studies comparing the anatomy and changes in colonic curvature when patients are in the prone position, which may help to prevent anterior bowing of the scope, particularly in patients with high body mass index (BMI).

Aims

To compare both the number of colonic curves and degree of change in curves with patients in supine versus prone positioning during computed tomography colonography (CTC).

Methods

75 CTC studies, obtained between January and April 2017 at Hotel Dieu Hospital in Kingston, Ontario, were screened and included based on image quality and adequacy of distention. Per standardized protocol, all patients undergoing CTC are imaged both in supine and prone positioning. Using an automated computer algorithm process developed for this study, curves were identified and measured via centerline points placed digitally through the colonic lumen, and compared between supine and prone patient positioning.

Results

75 colonographies were examined. The mean age was 68 years and 37/75 were male. BMI data was available for 56 patients, with mean BMI 29.4 (SD 5.7). There were no significant differences in total mean degrees of curvature between supine and prone positions [75.3 (SD 13.5) vs. 77.3 (SD 15.3), p=0.07], nor a significantly higher total number of curves &gt;100 degrees [4.0 (SD 2.0) vs. 4.5 (SD 2.3), p=0.14]. No significant correlation was seen between BMI and change in position (correlation factor 0.2, p=0.13).

Conclusions

No significant differences were found between the two positions during CT colonography. This certainly calls into question the strategy of starting in prone position, even in higher BMI patients. However, CT colonography doesn’t account for changes that can occur during colonoscopy, as the scope itself can dynamically affect angulations within the colon.

Funding Agencies

None

Measurement of electroweak production of a W boson in association with two jets in proton-proton collisions at s = 13 Te

A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton-proton collisions ats = 13 Te . The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9fb - 1 . The measurement is performed for the ℓ ν jj final state (with ℓ ν indicating a lepton-neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant massm jj > 120 Ge and transverse momentap T j > 25 Ge . The cross section of the process is measured in the electron and muon channels yieldingσ EW ( W jj ) = 6.23 ± 0.12 (stat) ± 0.61 (syst) pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are - 2.3 < c W W W / Λ 2 < 2.5 Te - 2 , - 8.8 < c W / Λ 2 < 16 Te - 2 , and - 45 < c B / Λ 2 < 46 Te - 2 . These results are combined with the CMS EW Zjj analysis, yielding the constraint on the c W W W coupling: - 1.8 < c W W W / Λ 2 < 2.0 Te - 2 .

Extraction and validation of a new set of CMS pythia8 tunes from underlying-event measurements

New sets of CMS underlying-event parameters ("tunes") are presented for the pythia8 event generator. These tunes use the NNPDF3.1 parton distribution functions (PDFs) at leading (LO), next-to-leading (NLO), or next-to-next-to-leading (NNLO) orders in perturbative quantum chromodynamics, and the strong coupling evolution at LO or NLO. Measurements of charged-particle multiplicity and transverse momentum densities at various hadron collision energies are fit simultaneously to determine the parameters of the tunes. Comparisons of the predictions of the new tunes are provided for observables sensitive to the event shapes at LEP, global underlying event, soft multiparton interactions, and double-parton scattering contributions. In addition, comparisons are made for observables measured in various specific processes, such as multijet, Drell-Yan, and top quark-antiquark pair production including jet substructure observables. The simulation of the underlying event provided by the new tunes is interfaced to a higher-order matrix-element calculation. For the first time, predictions from pythia8 obtained with tunes based on NLO or NNLO PDFs are shown to reliably describe minimum-bias and underlying-event data with a similar level of agreement to predictions from tunes using LO PDF sets.

Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets

Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at sqrt[s]=13  TeV, and correspond to an integrated luminosity of 35.9  fb^{-1}. The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.

Search for Low-Mass Quark-Antiquark Resonances Produced in Association with a Photon at sqrt[s]=13 TeV

A search for narrow low-mass resonances decaying to quark-antiquark pairs is presented. The search is based on proton-proton collision events collected at 13 TeV by the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 35.9  fb^{-1}, recorded in 2016. The search considers the case where the resonance has high transverse momentum due to initial-state radiation of a hard photon. To study this process, the decay products of the resonance are reconstructed as a single large-radius jet with two-pronged substructure. The signal would be identified as a localized excess in the jet invariant mass spectrum. No evidence for such a resonance is observed in the mass range 10 to 125 GeV. Upper limits at the 95% confidence level are set on the coupling strength of resonances decaying to quark pairs. The results obtained with this photon trigger strategy provide the first direct constraints on quark-antiquark resonance masses below 50 GeV obtained at a hadron collider.

Measurements of triple-differential cross sections for inclusive isolated-photon+jet events in p p collisions at s = 8 TeV

Measurements are presented of the triple-differential cross section for inclusive isolated-photon+jet events in p p collisions ats = 8 TeV as a function of photon transverse momentum ( p T γ ), photon pseudorapidity ( η γ ), and jet pseudorapidity ( η jet ). The data correspond to an integrated luminosity of 19.7 fb - 1 that probe a broad range of the available phase space, for| η γ | < 1.44 and1.57 < | η γ | < 2.50 ,| η jet | < 2.5 , 40 < p T γ < 1000 GeV , and jet transverse momentum, p T jet , > 25GeV . The measurements are compared to next-to-leading order perturbative quantum chromodynamics calculations, which reproduce the data within uncertainties.

Measurement of the average very forward energy as a function of the track multiplicity at central pseudorapidities in proton-proton collisions at s = 13 TeV

The average total energy as well as its hadronic and electromagnetic components are measured with the CMS detector at pseudorapidities - 6.6 < η < - 5.2 in proton-proton collisions at a centre-of-mass energys = 13 TeV . The results are presented as a function of the charged particle multiplicity in the region | η | < 2 . This measurement is sensitive to correlations induced by the underlying event structure over a very wide pseudorapidity region. The predictions of Monte Carlo event generators commonly used in collider experiments and ultra-high energy cosmic ray physics are compared to the data. All generators considered overestimate the fraction of energy going into hadrons.

Search for new physics in top quark production in dilepton final states in proton-proton collisions at s = 13 TeV

A search for new physics in top quark production is performed in proton-proton collisions at 13 TeV . The data set corresponds to an integrated luminosity of 35.9 fb - 1 collected in 2016 with the CMS detector. Events with two opposite-sign isolated leptons (electrons or muons), and b quark jets in the final state are selected. The search is sensitive to new physics in top quark pair production and in single top quark production in association with a W boson. No significant deviation from the standard model expectation is observed. Results are interpreted in the framework of effective field theory and constraints on the relevant effective couplings are set, one at a time, using a dedicated multivariate analysis. This analysis differs from previous searches for new physics in the top quark sector by explicitly separating t W from t t ¯  events and exploiting the specific sensitivity of the t W process to new physics.

Search for a Light Charged Higgs Boson Decaying to a W Boson and a CP-Odd Higgs Boson in Final States with eμμ or μμμ in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for a light charged Higgs boson (H^{+}) decaying to a W boson and a CP-odd Higgs boson (A) in final states with eμμ or μμμ is performed using data from pp collisions at sqrt[s]=13  TeV, recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9  fb^{-1}. In this search, it is assumed that the H^{+} boson is produced in decays of top quarks, and the A boson decays to two oppositely charged muons. The presence of signals for H^{+} boson masses between 100 and 160 GeV and A boson masses between 15 and 75 GeV is investigated. No evidence for the production of the H^{+} boson is found. Upper limits at 95% confidence level are obtained on the combined branching fraction for the decay chain, t→bH^{+}→bW^{+}A→bW^{+}μ^{+}μ^{-}, of 1.9×10^{-6} to 8.6×10^{-6}, depending on the masses of the H^{+} and A bosons. These are the first limits for these decay modes of the H^{+} and A bosons.

Azimuthal separation in nearly back-to-back jet topologies in inclusive 2- and 3-jet events in pp collisions at s = 13 Te

A measurement for inclusive 2- and 3-jet events of the azimuthal correlation between the two jets with the largest transverse momenta, Δ ϕ 12 , is presented. The measurement considers events where the two leading jets are nearly collinear ("back-to-back") in the transverse plane and is performed for several ranges of the leading jet transverse momentum. Proton-proton collision data collected with the CMS experiment at a center-of-mass energy of 13 Te and corresponding to an integrated luminosity of 35.9 fb - 1 are used. Predictions based on calculations using matrix elements at leading-order and next-to-leading-order accuracy in perturbative quantum chromodynamics supplemented with leading-log parton showers and hadronization are generally in agreement with the measurements. Discrepancies between the measurement and theoretical predictions are as large as 15%, mainly in the region177 ∘ < Δ ϕ 12 < 180 ∘ . The 2- and 3-jet measurements are not simultaneously described by any of models.

Measurement of exclusive ρ 770 0 photoproduction in ultraperipheral pPb collisions at s NN = 5.02 Te

Exclusiveρ 770 0 photoproduction is measured for the first time in ultraperipheral pPb collisions ats NN = 5.02 Te with the CMS detector. The cross section σ ( γ p → ρ 770 0 p ) is 11.0 ± 1.4 (stat) ± 1.0 (syst) μ b at ⟨ W γ p ⟩ = 92.6 Ge for photon-proton centre-of-mass energies W γ p between 29 and 213 Ge . The differential cross section d σ / d | t | is measured in the interval0.025 < | t | < 1 Ge 2 as a function of W γ p , where t is the squared four-momentum transfer at the proton vertex. The results are compared with previous measurements and theoretical predictions. The measured cross section σ ( γ p → ρ 770 0 p ) has a power-law dependence on the photon-proton centre-of-mass, consistent with electron-proton collision measurements performed at HERA. The W γ p dependence of the exponential slope of the differential cross section d σ / d | t | is also measured.

Studies of Beauty Suppression via Nonprompt D^{0} Mesons in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The transverse momentum spectra of D^{0} mesons from b hadron decays are measured at midrapidity (|y|<1) in pp and Pb-Pb collisions at a nucleon-nucleon center of mass energy of 5.02 TeV with the CMS detector at the LHC. The D^{0} mesons from b hadron decays are distinguished from prompt D^{0} mesons by their decay topologies. In Pb-Pb collisions, the B→D^{0} yield is found to be suppressed in the measured p_{T} range from 2 to 100  GeV/c as compared to pp collisions. The suppression is weaker than that of prompt D^{0} mesons and charged hadrons for p_{T} around 10  GeV/c. While theoretical calculations incorporating partonic energy loss in the quark-gluon plasma can successfully describe the measured B→D^{0} suppression at higher p_{T}, the data show an indication of larger suppression than the model predictions in the range of 2<p_{T}<5  GeV/c.

Search for a heavy pseudoscalar boson decaying to a Z and a Higgs boson at s = 13 Te

A search is presented for a heavy pseudoscalar boson A decaying to a Z  boson and a Higgs boson with mass of 125GeV . In the final state considered, the Higgs boson decays to a bottom quark and antiquark, and the Z  boson decays either into a pair of electrons, muons, or neutrinos. The analysis is performed using a data sample corresponding to an integrated luminosity of 35.9fb - 1 collected in 2016 by the CMS experiment at the LHC from proton-proton collisions at a center-of-mass energy of 13Te . The data are found to be consistent with the background expectations. Exclusion limits are set in the context of two-Higgs-doublet models in the A boson mass range between 225 and 1000GeV .

Search for supersymmetry in events with a photon, jets, b -jets, and missing transverse momentum in proton-proton collisions at 13 Te

A search for supersymmetry is presented based on events with at least one photon, jets, and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of 13 Te . The data correspond to an integrated luminosity of 35.9 fb - 1 and were recorded at the LHC with the CMS detector in 2016. The analysis characterizes signal-like events by categorizing the data into various signal regions based on the number of jets, the number of b -tagged jets, and the missing transverse momentum. No significant excess of events is observed with respect to the expectations from standard model processes. Limits are placed on the gluino and top squark pair production cross sections using several simplified models of supersymmetric particle production with gauge-mediated supersymmetry breaking. Depending on the model and the mass of the next-to-lightest supersymmetric particle, the production of gluinos with masses as large as 2120 Ge and the production of top squarks with masses as large as 1230 Ge are excluded at 95% confidence level.

Mutant IDH1 inhibitor ivosidenib (IVO; AG-120) in combination with azacitidine (AZA) for newly diagnosed acute myeloid leukemia (ND AML)

7011

Background: IVO, a mutant IDH1 (mIDH1) inhibitor, is approved for the treatment of relapsed/refractory mIDH1 AML. We report results from an ongoing phase 1b study of patients (pts) with mIDH1 ND AML ineligible for intensive treatment who received combination IVO+AZA (NCT02677922). Methods: Pts received oral IVO 500 mg daily continuously and subcutaneous AZA 75 mg/m2 on D1–7 in 28-d cycles. ORR comprised CR + CRi/CRp + PR+ MLFS. CR with partial hematologic recovery (CRh) was defined as CR with ANC > 0.5×109/L and platelets > 50×109/L. Exploratory analysis included digital PCR assessment of m IDH1 allele frequency in bone marrow mononuclear cells (≤0.04% sensitivity). Results: As of 9Oct2018, 23 pts received IVO+AZA (11 male; median age 76 yrs [range 61–88]). Median duration of exposure was 11 mo (0.3–25.3); 12 pts remained on treatment at data cutoff. All-grade adverse events (AEs) regardless of cause in ≥30% pts were thrombocytopenia (65%), nausea (61%), diarrhea (57%), anemia (52%), constipation (52%), febrile neutropenia (39%), pyrexia (39%), vomiting (35%), fatigue (35%), hypokalemia (35%), dizziness (35%), insomnia (35%), and neutropenia (30%). AEs of special interest included ECG QT prolonged (26%), IDH differentiation syndrome (17%), and leukocytosis (13%). Grade 3/4 AEs in ≥10% pts were thrombocytopenia (61%), anemia (44%), febrile neutropenia (39%), neutropenia (26%), sepsis (22%), and ECG QT prolonged (13%). ORR was 78% (n = 18): CR 57%, CRi/CRp 13%, and MLFS 9%. CR+CRh rate was 70% (n = 16). Median time to response was 1.8 mo (0.7–3.8) and to CR 3.5 mo (0.8–6.0); median response duration not yet reached. m IDH1 clearance was seen in 10/16 pts (63%) with CR/CRh, including 9/13 (69%) with CR. Conclusions: IVO+AZA was well tolerated with a safety profile consistent with IVO or AZA monotherapy. All-grade cytopenia-related AEs were infrequent relative to other non-intensive therapies. CR and ORR rates exceeded those of AZA alone (Dombret et al., Blood 2015) and most responders achieved m IDH1 mutation clearance. Based on these findings, a phase 3 double-blind placebo-controlled study of IVO +AZA (AGILE, NCT03173248) is actively enrolling pts. Clinical trial information: NCT02677922.

Combined measurements of Higgs boson couplings in proton-proton collisions at s = 13 Te

Combined measurements of the production and decay rates of the Higgs boson, as well as its couplings to vector bosons and fermions, are presented. The analysis uses the LHC proton-proton collision data set recorded with the CMS detector in 2016 ats = 13 Te , corresponding to an integrated luminosity of 35.9fb - 1 . The combination is based on analyses targeting the five main Higgs boson production mechanisms (gluon fusion, vector boson fusion, and associated production with a W or Z boson, or a top quark-antiquark pair) and the following decay modes: H → γ γ , Z Z , W W , τ τ , b b , and μ μ . Searches for invisible Higgs boson decays are also considered. The best-fit ratio of the signal yield to the standard model expectation is measured to be μ = 1.17 ± 0.10 , assuming a Higgs boson mass of 125.09 Ge . Additional results are given for various assumptions on the scaling behavior of the production and decay modes, including generic parametrizations based on ratios of cross sections and branching fractions or couplings. The results are compatible with the standard model predictions in all parametrizations considered. In addition, constraints are placed on various two Higgs doublet models.

Measurement of the t t ¯ production cross section, the top quark mass, and the strong coupling constant using dilepton events in pp collisions at s = 13 Te

A measurement of the top quark-antiquark pair production cross section σ t t ¯ in proton-proton collisions at a centre-of-mass energy of 13Te is presented. The data correspond to an integrated luminosity of 35.9 fb - 1 , recorded by the CMS experiment at the CERN LHC in 2016. Dilepton events ( e ± μ ∓ ,μ + μ - ,e + e - ) are selected and the cross section is measured from a likelihood fit. For a top quark mass parameter in the simulation ofm t MC = 172.5 Ge the fit yields a measured cross sectionσ t t ¯ = 803 ± 2 (stat) ± 25 (syst) ± 20 (lumi) pb , in agreement with the expectation from the standard model calculation at next-to-next-to-leading order. A simultaneous fit of the cross section and the top quark mass parameter in the powheg simulation is performed. The measured value ofm t MC = 172.33 ± 0.14 (stat) - 0.72 + 0.66 (syst) Ge is in good agreement with previous measurements. The resulting cross section is used, together with the theoretical prediction, to determine the top quark mass and to extract a value of the strong coupling constant with different sets of parton distribution functions.