Abstract
The SuperCDMS SNOLAB dark matter search experiment aims to
be sensitive to energy depositions down to
(1 eV). This imposes requirements on the resolution,
signal efficiency, and noise ...rejection of the trigger system. To
accomplish this, the SuperCDMS level-1 trigger system is implemented
in an FPGA on a custom PCB. A time-domain optimal filter algorithm
realized as a finite impulse response filter provides a baseline
resolution of 0.38 times the standard deviation of the noise,
σ
n
, and a 99.9% trigger efficiency for signal
amplitudes of 1.1 σ
n
in typical noise
conditions. Embedded in a modular architecture, flexible trigger
logic enables reliable triggering and vetoing in a dead-time-free
manner for a variety of purposes and run conditions. The trigger
architecture and performance are detailed in this article.
G4CMP simulates phonon and charge transport in cryogenic semiconductor crystals using the Geant4 toolkit. The transport code is capable of simulating the propagation of acoustic phonons as well as ...electron and hole charge carriers. Herein processes for anisotropic phonon propagation, oblique charge-carrier propagation, and phonon emission by accelerated charge carriers are included. The simulation reproduces theoretical predictions and experimental observations such as phonon caustics, heat-pulse propagation times, and mean charge-carrier drift velocities. In addition to presenting the physics and features supported by G4CMP, this report outlines example applications from the dark matter and quantum information science communities. These communities are applying G4CMP to model and design devices for which the energy transported by phonons and charge carriers is germane to the performance of superconducting instruments and circuits placed on silicon and germanium substrates. The G4CMP package is available to download from GitHub: github.com/kelseymh/G4CMP.
The Cryogenic Dark Matter Search low ionization threshold experiment (CDMSlite) searches for interactions between dark matter particles and germanium nuclei in cryogenic detectors. The experiment has ...achieved a low energy threshold with improved sensitivity to low-mass (<10 GeV/c2) dark matter particles. We present an analysis of the final CDMSlite dataset, taken with a different detector than was used for the two previous CDMSlite datasets. This analysis includes a data "salting" method to protect against bias, improved noise discrimination, background modeling, and the use of profile likelihood methods to search for a dark matter signal in the presence of backgrounds. We achieve an energy threshold of 70 eV and significantly improve the sensitivity for dark matter particles with masses between 2.5 and 10 GeV/c2 compared to previous analyses. We set an upper limit on the dark matter-nucleon scattering cross section in germanium of 5.4×10-42 cm2 at 5 GeV/c2, a factor of ~2.5 improvement over the previous CDMSlite result.
Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by ...cosmogenic radiation inside the germanium. There are limited experimental data available to constrain production rates and a large spread of theoretical predictions. We examine the calculation of expected production rates, and analyze data from the second run of the CDMS low ionization threshold experiment (CDMSlite) to estimate the rates for several isotopes. We model the measured CDMSlite spectrum and fit for contributions from tritium and other isotopes. Using the knowledge of the detector history, these results are converted to cosmogenic production rates at sea level. The production rates in atoms/(kg·day) are 74±9 for 3H, 1.5±0.7 for 55Fe, 17±5 for 65Zn, and 30±18 for 68Ge.
Future direct searches for low-mass dark matter particles with germanium detectors, such as SuperCDMS SNOLAB, are expected to be limited by backgrounds from radioactive isotopes activated by ...cosmogenic radiation inside the germanium. There are limited experimental data available to constrain production rates and a large spread of theoretical predictions. We examine the calculation of expected production rates, and analyze data from the second run of the CDMS low ionization threshold experiment (CDMSlite) to estimate the rates for several isotopes. We model the measured CDMSlite spectrum and fit for contributions from tritium and other isotopes. Using the knowledge of the detector history, these results are converted to cosmogenic production rates at sea level. The production rates in atoms/(kg$\cdot$day) are 74$\pm$9 for $^3$H, 1.5$\pm$0.7 for $^{55}$Fe, 17$\pm$5 for $^{65}$Zn, and 30$\pm$18 for $^{68}$Ge.
G4CMP simulates phonon and charge transport in cryogenic semiconductor crystals using the Geant4 toolkit. The transport code is capable of simulating the propagation of acoustic phonons as well as ...electron and hole charge carriers. Processes for anisotropic phonon propagation, oblique charge-carrier propagation, and phonon emission by accelerated charge carriers are included. The simulation reproduces theoretical predictions and experimental observations such as phonon caustics, heat-pulse propagation times, and mean charge-carrier drift velocities. In addition to presenting the physics and features supported by G4CMP, this report outlines example applications from the dark matter and quantum information science communities. These communities are applying G4CMP to model and design devices for which the energy transported by phonons and charge carriers is germane to the performance of superconducting instruments and circuits placed on silicon and germanium substrates. The G4CMP package is available to download from GitHub: github.com/kelseymh/G4CMP.
Placenta accreta spectrum (PAS) disorders (with increasing order of the depth of invasion: accreta, increta, percreta) are quite challenging for the purpose of diagnosis and treatment. Pathological ...examination or imaging evaluation are not very dependable when considered as stand-alone diagnostic tools. On the other hand, timely diagnosis is of great importance, as maternal and fetal mortality drastically increases if patient goes through the third phase of delivery in a not well-suited facility. A multidisciplinary approach for diagnosis (incorporating clinical, imaging, and pathological evaluation) is mandatory, particularly in complicated cases. For imaging evaluation, the diagnostic modality of choice in most scenarios is ultrasound (US) exam; patients are referred for MRI when US is equivocal, inconclusive, or not visualizing placenta properly. Herewith, we review the reported US and MRI features of PAS disorders (mainly focusing on MRI), going over the normal placental imaging and imaging pitfalls in each section, and lastly, covering the imaging findings of PAS disorders in the first trimester and cesarean section pregnancy (CSP).
Despite growing evidence for the association between other dietary macronutrients and bone health, limited and inconsistent knowledge is available regarding carbohydrate intake. In this systematic ...review and meta-analysis, we purposed to clarify and synthesize the knowledge about the relation between carbohydrate intake and the risk of fracture.
Systematic review and meta-analysis of observational studies.
In this study, PubMed and Scopus were used to conduct a comprehensive search for articles published up to September 2018. The screening was done independently by two authors. Pooled effect sizes were calculated using fixed and random effect models for the highest versus lowest intake categories. The dose–response nature of the relationship was also investigated.
No association was observed between carbohydrate intake and the risk of fracture in high versus low intake meta-analysis (overall relative risk RR: 1.24; 95% confidence interval 95% CI: 0.84–1.84; P = 0.27) with moderate heterogeneity (I2 = 57.7%, P heterogeneity = 0.05). Moreover, there was no relationship between carbohydrate intake and the risk of fracture in both linear (overall RR: 1.00; 95% CI: 0.94–1.05; P = 0.88) (I2 = 68.1%, P heterogeneity = 0.48) and nonlinear (Pnon-linearity = 0.14) models.
No association was observed between carbohydrate intake and the risk of fracture.
•No association was observed between carbohydrate intake and the risk of fracture in high versus low intake meta-analysis.•No relationship was found between carbohydrate intake and the risk of fracture in linear model.•No relationship was found between carbohydrate intake and the risk of fracture in nonlinear model.
Abstract
Study question
Does supplementing in vitro maturation (IVM) medium with bone marrow mesenchymal stem cell-conditioned medium (BMSC-CM), L-carnitine (LC), and Repaglinide (RG) enhance the ...developmental competence of oocytes derived from endometriosis-induced mice?
Summary answer
L-carnitine and BMSC-CM supplementation improved maturation and fertilization, and developmental competence of oocytes following IVF by modulating nitro-oxidative stress and accelerating nuclear maturation of oocytes.
What is known already
Endometriosis (EMS) is a detrimental condition of the female reproductive system affecting up to 15% of women of reproductive age. Oocytes retrieved from EMS-affected ovaries are more likely to fail IVM and to show altered morphology and lower cytoplasmic mitochondrial content. Mesenchymal stem cells (MSCs) secrete various types of cytokines, growth factors, bioactive factors, and tissue regenerative components into mesenchymal stem cell-conditioned medium. L-carnitine is an antioxidant playing an important role in cell metabolism and is crucial for fatty acid metabolism. Repaglinide (RG) is an anti-hyperglycemic medication that induces insulin secretion by attaching to β cells of the pancreas.
Study design, size, duration
To induce EMS, two groups of mice were used. The first group, as donor mice, were intraperitoneally injected with estradiol-17β depot for one week. Then, they were sacrificed on day 14, and their uterine horns were removed. The suspension including tissue fragments from uterine horns was injected intraperitoneally to the recipient mice group. To ensure the induction of EMS, ovaries of some mice in both normal and EMS groups were analyzed by histological examination.
Participants/materials, setting, methods
Adult female NMRI mice (6-8 weeks old) were divided into two normal and EMS-induced mice. Oocytes obtained from normal and EMS-induced mice were cultured in the IVM medium supplemented with RG, LC, and BMSC-CM for 24 hours. Subsequently, IVM, IVF, embryo development rates, blastocyst cell numbers were assessed. Moreover, the levels of reactive oxygen species (ROS), nitric oxide (NO), and total antioxidant capacity (TAC) of the IVM medium were evaluated.
Main results and the role of chance
Microscopic studies of ovarian tissue samples showed that folliculogenesis, quality of follicles, and oocyte quality reduced in the EMS-induced group. The IVM results represent that 0.3 mg/ml and 0.6 mg/ml of LC, and 25% and 50% of BMSC-CM enhanced the percentage of MII oocytes significantly. Indeed, the highest IVM rate in both the normal and EMS-induced mice was observed in the BMSC-CM 50% group. More importantly, 0.3 and 0.6 mg/ml of LC, and 25% and 50% of BMSC-CM treatments showed a dramatic decrease in ROS and NO levels and a significant enhancement in TAC levels compared to the control group. Our results also indicated that there was a substantial improvement in terms of IVF, cleavage, and blastocyst rates in all treatment groups compared to the control group. The highest blastocyst formation rate was obtained in 50% of the BMSC-CM group. In normal groups, there was a dramatic increase in the mean of total cell number and TE cells in 1µM RG, 0.3 and 0.6 mg/ml LC, 25% and 50% BMSC-CM. In EMS-induced groups, except for the 1M RG group, all treatment groups exhibited a significant difference in the mean total cell population and TE cells compared to the control group.
Limitations, reasons for caution
Due to limited laboratory facilities, the levels of growth factors, pro-inflammatory cytokines, anti-apoptotic, and antioxidants were not measured in the IVM medium. We, therefore, do not know which of the constituents of the BMSC-CM, in particular, had promoter effects on the oocyte maturation, fertilization, and developmental competence of IVF embryos.
Wider implications of the findings
These approaches may outline the clinical applications of LC and BMSC-CM in the assisted reproductive technology (ART) setting and pave the way to improve the maturation culture. Also, these findings can advance the efficiency of fertility outcomes in endometriosis-related infertile couples.
Trial registration number
N/A
Endometriosis (EMS) is one of the most prevalent causes for female infertility. Herein, we investigated the effect of the repaglinide (RG), L-carnitine (LC), and bone marrow mesenchymal stem ...cell-conditioned medium (BMSC-CM) supplementation during in vitro maturation (IVM) on the quality, maturation, and fertilization rates, as well as embryonic quality and development of oocytes derived from normal and EMS mouse model. Immature oocytes were collected from two groups of normal and EMS-induced female NMRI mice at 6-8 weeks of age. Oocytes were cultured in IVM medium unsupplemented (control group), or supplemented with 1 M RG, 0.3 and 0.6 mg/mL LC, and 25 and 50% BMSC-CM. After 24 h of oocyte incubation, IVM rate and antioxidant status were assessed. Subsequently, the rates of fertilization, cleavage, blastulation, and embryonic development were assessed. Our results demonstrated that supplementation of IVM medium with LC and BMSC-CM, especially 50% BMSC-CM, significantly enhanced IVM and fertilization rates, and markedly improved blastocyst development and total blastocyst cell numbers in EMS-induced mice compared to the control group (53.28±0.24 vs 18.09±0.10%). Additionally, LC and BMSC-CM were able to significantly modulate EMS-induced nitro-oxidative stress by boosting total antioxidant capacity (TAC) and mitigating nitric oxide (NO) levels. Collectively, LC and BMSC-CM supplementation improved oocyte quality and IVM rates, pre-implantation developmental competence of oocytes after in vitro fertilization, and enhanced total blastocyst cell numbers probably by attenuating nitro-oxidative stress and accelerating nuclear maturation of oocytes. These outcomes may provide novel approaches to refining the IVM conditions that can advance the efficiency of assisted reproductive technologies in infertile couples.
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