Tests of Light-Lepton Universality in Angular Asymmetries of B^{0}→D^{*-}ℓν Decays

We present the first comprehensive tests of the universality of the light leptons in the angular distributions of semileptonic B^{0}-meson decays to charged spin-1 charmed mesons. We measure five angular-asymmetry observables as functions of the decay recoil that are sensitive to lepton-universality-violating contributions. We use events where one neutral B is fully reconstructed in ϒ(4S)→BB[over ¯] decays in data corresponding to 189  fb^{-1} integrated luminosity from electron-positron collisions collected with the Belle II detector. We find no significant deviation from the standard model expectations.

Precise Measurement of the D_{s}^{+} Lifetime at Belle II

We measure the lifetime of the D_{s}^{+} meson using a data sample of 207  fb^{-1} collected by the Belle II experiment running at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The lifetime is determined by fitting the decay-time distribution of a sample of 116×10^{3} D_{s}^{+}→ϕπ^{+} decays. Our result is τ_{D_{s}^{+}}=(499.5±1.7±0.9)  fs, where the first uncertainty is statistical and the second is systematic. This result is significantly more precise than previous measurements.

Search for a τ^{+}τ^{-} Resonance in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} Events with the Belle II Experiment

We report the first search for a nonstandard-model resonance decaying into τ pairs in e^{+}e^{-}→μ^{+}μ^{-}τ^{+}τ^{-} events in the 3.6-10  GeV/c^{2} mass range. We use a 62.8  fb^{-1} sample of e^{+}e^{-} collisions collected at a center-of-mass energy of 10.58 GeV by the Belle II experiment at the SuperKEKB collider. The analysis probes three different models predicting a spin-1 particle coupling only to the heavier lepton families, a Higgs-like spin-0 particle that couples preferentially to charged leptons (leptophilic scalar), and an axionlike particle, respectively. We observe no evidence for a signal and set exclusion limits at 90% confidence level on the product of cross section and branching fraction into τ pairs, ranging from 0.7 to 24 fb, and on the couplings of these processes. We obtain world-leading constraints on the couplings for the leptophilic scalar model for masses above 6.5  GeV/c^{2} and for the axionlike particle model over the entire mass range.

Measurement of CP Violation in B^{0}→K_{S}^{0}π^{0} Decays at Belle II

We report a measurement of the CP-violating parameters C and S in B^{0}→K_{S}^{0}π^{0} decays at Belle II using a sample of 387×10^{6}  BB[over ¯] events recorded in e^{+}e^{-} collisions at a center-of-mass energy corresponding to the ϒ(4S) resonance. These parameters are determined by fitting the proper decay-time distribution of a sample of 415 signal events. We obtain C=-0.04_{-0.15}^{+0.14}±0.05 and S=0.75_{-0.23}^{+0.20}±0.04, where the first uncertainties are statistical and the second are systematic.

Test of Light-Lepton Universality in the Rates of Inclusive Semileptonic B-Meson Decays at Belle II

We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/μ})=B(B→Xeν)/B(B→Xμν), a precision test of electron-muon universality, using data corresponding to 189  fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3  GeV/c to obtain R(X_{e/μ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.

Search for an Invisible Z^{'} in a Final State with Two Muons and Missing Energy at Belle II

The L_{μ}-L_{τ} extension of the standard model predicts the existence of a lepton-flavor-universality-violating Z^{'} boson that couples only to the heavier lepton families. We search for such a Z^{'} through its invisible decay in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'}. We use a sample of electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019-2020, corresponding to an integrated luminosity of 79.7  fb^{-1}. We find no excess over the expected standard-model background. We set 90%-confidence-level upper limits on the cross section for this process as well as on the coupling of the model, which ranges from 3×10^{-3} at low Z^{'} masses to 1 at Z^{'} masses of 8  GeV/c^{2}.

Search for Lepton-Flavor-Violating τ Decays to a Lepton and an Invisible Boson at Belle II

We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→μ^{-}α decays, where α is an invisible spin-0 boson. The search uses electron-positron collisions at 10.58 GeV center-of-mass energy with an integrated luminosity of 62.8  fb^{-1}, produced by the SuperKEKB collider and collected with the Belle II detector. We search for an excess in the lepton-energy spectrum of the known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} and τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ} decays. We report 95% confidence-level upper limits on the branching-fraction ratio B(τ^{-}→e^{-}α)/B(τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ}) in the range (1.1-9.7)×10^{-3} and on B(τ^{-}→μ^{-}α)/B(τ^{-}→μ^{-}ν[over ¯]_{μ}ν_{τ}) in the range (0.7-12.2)×10^{-3} for α masses between 0 and 1.6  GeV/c^{2}. These results provide the most stringent bounds on invisible boson production from τ decays.

Observation of e^{+}e^{-}→ωχ_{bJ}(1P) and Search for X_{b}→ωϒ(1S) at sqrt[s] near 10.75 GeV

We study the processes e^{+}e^{-}→ωχ_{bJ}(1P) (J=0, 1, or 2) using samples at center-of-mass energies sqrt[s]=10.701, 10.745, and 10.805 GeV, corresponding to 1.6, 9.8, and 4.7  fb^{-1} of integrated luminosity, respectively. These data were collected with the Belle II detector during special operations of the SuperKEKB collider above the ϒ(4S) resonance. We report the first observation of ωχ_{bJ}(1P) signals at sqrt[s]=10.745  GeV. By combining Belle II data with Belle results at sqrt[s]=10.867  GeV, we find energy dependencies of the Born cross sections for e^{+}e^{-}→ωχ_{b1,b2}(1P) to be consistent with the shape of the ϒ(10753) state. These data indicate that the internal structures of the ϒ(10753) and ϒ(10860) states may differ. Including data at sqrt[s]=10.653  GeV, we also search for the bottomonium equivalent of the X(3872) state decaying into ωϒ(1S). No significant signal is observed for masses between 10.45 and 10.65  GeV/c^{2}.

Search for a Dark Photon and an Invisible Dark Higgs Boson in μ^{+}μ^{-} and Missing Energy Final States with the Belle II Experiment

The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→μ^{+}μ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34  fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0  GeV/c^{2}<M_{A^{'}}<9.7  GeV/c^{2} and for the h^{'} mass M_{h^{'}}<M_{A^{'}}, where ϵ is the mixing strength between the standard model and the dark photon and α_{D} is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.

Precise Measurement of the D^{0} and D^{+} Lifetimes at Belle II

We report a measurement of the D^{0} and D^{+} lifetimes using D^{0}→K^{-}π^{+} and D^{+}→K^{-}π^{+}π^{+} decays reconstructed in e^{+}e^{-}→cc[over ¯] data recorded by the Belle II experiment at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data, collected at center-of-mass energies at or near the ϒ(4S) resonance, correspond to an integrated luminosity of 72  fb^{-1}. The results, τ(D^{0})=410.5±1.1(stat)±0.8(syst)  fs and τ(D^{+})=1030.4±4.7(stat)±3.1(syst)  fs, are the most precise to date and are consistent with previous determinations.

Search for B^{+}→K^{+}νν[over ¯] Decays Using an Inclusive Tagging Method at Belle II

A search for the flavor-changing neutral-current decay B^{+}→K^{+}νν[over ¯] is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63  fb^{-1} collected at the ϒ(4S) resonance and a sample of 9  fb^{-1} collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B^{+}→K^{+}νν[over ¯] decay, but also the inclusive properties of the other B meson in the ϒ(4S)→BB[over ¯] event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B^{+}→K^{+}νν[over ¯] of 4.1×10^{-5} is set at the 90% confidence level.

Search for Axionlike Particles Produced in e^{+}e^{-} Collisions at Belle II

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e^{+}e^{-}→γa, a→γγ in the mass range 0.2<m_{a}<9.7  GeV/c^{2} using data corresponding to an integrated luminosity of (445±3)  pb^{-1}. Light pseudoscalars interacting predominantly with standard model gauge bosons (so-called axionlike particles or ALPs) are frequently postulated in extensions of the standard model. We find no evidence for ALPs and set 95% confidence level upper limits on the coupling strength g_{aγγ} of ALPs to photons at the level of 10^{-3}  GeV^{-1}. The limits are the most restrictive to date for 0.2<m_{a}<1  GeV/c^{2}.

Search for an Invisibly Decaying Z^{'} Boson at Belle II in e^{+}e^{-}→μ^{+}μ^{-}(e^{±}μ^{∓}) Plus Missing Energy Final States

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z^{'}. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z^{'} in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'} and of a lepton-flavor-violating Z^{'} in e^{+}e^{-}→e^{±}μ^{∓}Z^{'}. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an L_{μ}-L_{τ} theory, into upper limits on the Z^{'} coupling constant at the level of 5×10^{-2}-1 for M_{Z^{'}}≤6  GeV/c^{2}.

Electromyographic Responses from the Vastus Medialis during Isometric Muscle Actions

This study examined the electromyographic (EMG) responses from the vastus medialis (VM) for electrodes placed over and away from the innervation zone (IZ) during a maximal voluntary isometric contraction (MVIC) and sustained, submaximal isometric muscle action. A linear electrode array was placed on the VM to identify the IZ and muscle fiber pennation angle during an MVIC and sustained isometric muscle action at 50% MVIC. EMG amplitude and frequency parameters were determined from 7 bipolar channels of the electrode array, including over the IZ, as well as 10 mm, 20 mm and 30 mm proximal and distal to the IZ. There were no differences between the channels for the patterns of responses for EMG amplitude or mean power frequency during the sustained, submaximal isometric muscle action; however, there were differences between channels during the MVIC. The results of the present study supported the need to standardize the placement of electrodes on the VM for the assessment of EMG amplitude and mean power frequency. Based on the current findings, it is recommended that electrode placements be distal to the IZ and aligned with the muscle fiber pennation angle during MVICs, as well as sustained, submaximal isometric muscle actions.

Müllerian duct anomalies: MR imaging evaluation

Twenty-nine patients underwent magnetic resonance (MR) imaging for investigation of müllerian duct anomalies (MDAs). The anomalies evaluated were uterine agenesis (n = 2), uterine hypoplasia (n = 5), unicornuate uterus (n = 5), uterus didelphys (n = 5), bicornuate uterus (n = 10), and septate uterus (n = 2). The MR imaging interpretation was correlated with results of laparotomy (n = 18), hysterosalpingography (HSG) (n = 5), laparoscopy (n = 2), hysteroscopy (n = 1), HSG and laparotomy (n = 2), and HSG and laparoscopy (n = 1). MR imaging enabled correct classification of the anomaly in each patient and identification of coincidental gynecologic disease in 10 patients (34%). MR imaging results influenced clinical treatment in six (24%) of 25 patients referred prospectively. Of particular value was the ability to characterize septal tissue (myometrium versus fibrous tissue), identify the patients in whom the septum of bicornuate uteri had both fibrous and myometrial components, and establish that suspected adnexal lesions were actually components of obstructed MDAs.

Vaginal reconstruction after exenteration with use of gracilis myocutaneous flaps: the University of California, San Francisco experience

At the University of California, San Francisco Medical Center we have performed 18 vaginal reconstructive procedures with gracilis flaps at the time of anterior, posterior, or total pelvic exenteration. We have compared these patients with 13 other patients undergoing exenteration during the same interval who chose not to have vaginal reconstruction. There was no significant difference between the two groups with respect to age, weight, operating time, blood loss, or duration of postoperative hospitalization, but there were significantly fewer serious complications in the patients receiving gracilis flaps. The results of a questionnaire indicated that the perineal cosmetic results are highly acceptable, although residual scarring on the legs is a common source of minor complaint. Sexual adjustment can be complete or nearly complete in surviving patients. Given the major contribution to wound healing, reduced postoperative morbidity, excellent cosmetic results, and the opportunity for complete sexual rehabilitation, we believe the gracilis myocutaneous flap neovagina remains the procedure of choice for most women undergoing major exenterative procedures.

Vaginal adenosis in women born prior to the diethylstilbestrol era

Vaginal adenosis was evaluated in 41 women, all of whom had been born prior to the diethylstilbestrol (DES) era, and compared with the adenosis commonly encountered in DES-exposed progeny. The patients were 24 to 88 years of age (median, 44 years). Six of the women were symptomatic, and in four of these six the glands were enmeshed in a marked inflammatory infiltrate. In an additional 26 women the adenosis was discovered as incidental, nonsymptomatic macroscopic nodules or cysts. The remaining nine cases of adenosis were discovered by pathologists. Three types of epithelia characterized the glands: mucinous, tuboendometrial, and embryonic. Mucinous columnar cells resembling the lining of the normal endocervix and tuboendometrial cells resembling the lining of the normal fallopian tube or endometrium constituted the glands exclusively in 22 and eight specimens, respectively, and as a mixture in seven. The glands lined by mucinous cells most often presented clinically as cysts or nodules. The specimens composed of tuboendometrial cells were most often discovered on microscopic examination. The third type of epithelium, composed of embryonic columnar cells, was encountered in four specimens. These glands, less than 30 micron in greatest diameter, were located at the junction between the lamina propria and the squamous epithelium, and were incidental microscopic findings. It is concluded that the microscopic appearances of adenosis in women born prior to the DES era are identical to those encountered in young women exposed in utero to DES.

Chlamydia trachomatis and cervical neoplasia

We tested 383 women with and 500 women without cervical neoplasia for antibodies against Chlamydia trachomatis or herpes simplex virus (HSV). Exposure to both agents was related to sexual activity, with the highest prevalence of antibodies found in women with more sex partners and who had first coitus at an earlier age. When subjects were matched for several risk factors (age, race, marital status, parity, number of sex partners, and history of venereal disease), a significant excess of antibodies against C trachomatis was found in cases as compared with control subjects (76.5% v 58.4%, respectively; n = 149). Because matched-pair analysis lost a substantial proportion of women with neoplasia (largely because they were older), linear logistic analysis was performed. This also showed an excess of antichlamydial antibody in cases, with an estimated odds ratio of approximately 2 for the association of antichlamydial antibody and the risk of being a case. Neither analysis found an excess of antibodies to HSV type 2 in cases.

Radical surgery in the management of clear cell adenocarcinoma of the cervix and vagina in young women

The treatment of clear cell adenocarcinoma of the cervix and vagina in young women has varied widely from one institution to another. Since 1956, 16 such patients have been treated primarily with radical surgery at the University of California, San Francisco. The operations have ranged from radical hysterectomy and bilateral pelvic lymph node dissection with preservation of the ovaries to total pelvic exenteration, depending upon the location and extent of the disease. Vaginal reconstruction has been carried out in most of the patients who required vaginectomy. Eleven of the 16 patients are living and well. The remaining five have died of disease, two of them after relatively long disease-free intervals.

Radical surgery for the treatment of early invasive cervical carcinoma (stage IB): review of 15 years' experience

From 1963 through 1977, 108 patients with stage IB cervical carcinoma were treated with radical hysterectomy and pelvic lymphadenectomy at the University of California, San Francisco. Forty-four of 48 patients followed for 5 or more years after surgery are known to be alive (5-year survival rate, 91.7%). The 5-year survival rate of all 108 patients using the life-table method is 93.4%. Complications in this series were few; only 1 patient developed a ureterovaginal fistula.

Chlamydial infection in women with cervical dysplasia

The prevalence of antibodies to chlamydiae, particularly to TRIC (trachoma-inclusion conjunctivitis) agents, was studied in women with cervical dysplasia and in women attending selected clinics (obstetrics, cancer-screening, and gynecology). In addition, attempts were made to isolate TRIC agents and herpesviruses from the cervices of these women. TRIC agent recovery rates 4.1 per cent for women with dysplasia, 5.4 per cent for pregnant women, 7.8 per cent in the women's clinic, and 0.8 per cent in the cancer-screening clinic. Herpesvirus recovery rates were lower, on the order of 1 per cent or less in each clinic. Complement-fixing antibodies to chlamydial group antigen were detected in 21.5 per cent of women with dysplasia. With a more sensitive fluorescent antibody method, 77.6 per cent of the women with dysplasia or cervical cancer were shown to have antibodies to chlamydiae. In general, antichlamydial antibodies were less prevalent in the other clinic populations. The results of this study indicate that women with cervical dysplasia or cancer may have a high prevalence of antibodies to sexually transmitted agents other than herpesvirus type 2.

Are chlamydial infections the most prevalent venereal disease?

We studied two population groups (more than 1,600 patients) to determine the prevalence and clinical associations of genital tract infections with chlamydiae and herpesviruses. Base-line isolation rates for asymptomatic women having routine pelvic examinations were much lower than rates for symptomatic women. In both groups, chlamydiae were more prevalent than herpesviruses. Chlamydial infection was associated much more commonly with cervicitis (36.6%) than with vaginitis only (4.1%). Among 282 symptomatic men, the cultures of 19.9% yielded chlamydiae, and 4.3%, herpesviruses. Chlamydiae were recovered from 35.5% (27 of 76) of specimens from men with nongonococcal urethritis, and from an even larger proportion, 57% (24 of 42), of the specimens from men with frank discharge.

Florida Citrus Molasses as a Fermentation Substrate

Samples of midseason Florida citrus molasses from 10 different manufacturing plants were studied during 2 years of production for suitability as fermentation substrates. They were analyzed for degrees Brix, p H, percentage of protein, and free amino acid content. The following ranges of values were obtained: degrees Brix, 65.4 to 73.0; p H, 4.2 to 6.4; and protein, 3.3 to 5.1%. Although the general characteristics of all samples were quite similar, the total free amino acid content and the number of amino acids differed from year to year and from plant to plant. The free amino acids consistently present were asparagine, aspartic acid, alanine, γ-amino-butyric, glycine, glutamic acid, proline, serine, and threonine. Occasionally found were arginine, histidine, isoleucine, leucine, lysine, phenylalanine, tyrosine, and valine. An extremely high level of proline was detected in all samples.

THE EFFECT OF ULTRA-VIOLET, X-RAY, AND RADIUM RADIATION ON THE TOXICITY OF NORMAL BLOOD

While the number of experiments performed is perhaps somewhat limited the results obtained were quite definite and warrant the following conclusions. The toxicity of normal blood for living plant protoplasm as studied on the growth of Lupinus albus seedlings is definitely influenced by various radiations. Ultra-violet rays produce no effect on normal blood or may even render it slightly less toxic. Roentgen rays render normal blood more toxic. The toxicity is greater in the case of the blood plasma as compared with the blood cells and a more toxic effect is produced with the Coolidge tube as compared with the gas tube. Radium emanations in the few experiments performed produced changes very much the same as those given by the x-rays.