Context
. The Hubble diagram of type-Ia supernovae (SNe-Ia) provides cosmological constraints on the nature of dark energy with an accuracy limited by the flux calibration of currently available ...spectrophotometric standards. This motivates new developments to improve the link between existing astrophysical flux standards and laboratory standards.
Aims
. The StarDICE experiment aims to establish a five-stage metrology chain from NIST photodiodes to stars, with a targeted accuracy of 1 mmag in
griz
colors. We present the first two stages, resulting in the calibration transfer from NIST photodiodes to a demonstration 150 mpixel CMOS sensor (Sony IMX411ALR as implemented in the QHY411M camera by QHYCCD). As a side-product, we provide full characterization of this camera, which we believe to be of potential interest in astronomical imaging and photometry and specifically discuss its use in the context of gravitational wave optical follow-up.
Methods.
A fully automated spectrophotometric bench was built to perform the calibration transfer. The sensor readout electronics was studied using thousands of flat-field images from which we derived stability, high-resolution photon transfer curves (PTC), and estimates of the individual pixel gain. The sensor quantum efficiency (QE) was then measured relatively to a NIST-calibrated photodiode, in a well-defined monochromatic light beam from 375 to 1078 nm. Last, flat-field scans at 16 different wavelengths were used to build maps of the sensor response, fully characterizing the sensor for absolute photometric measurements.
Results.
We demonstrated statistical uncertainty on QE below 0.001 e
−
/
γ
between 387 nm and 950 nm, the range being limited by the sensitivity decline of the tested sensor in the infrared. Systematic uncertainties in the bench optics are controlled at the level of 1 × 10
−3
e
−
/
γ
. Linearity issues are detected at the level of 5 × 10
−3
e
−
/
γ
for the tested camera and require further developments to fully correct. Uncertainty in the overall normalization of the QE curve (without relevance for the cosmology, but relevant to evaluate the performance of the camera itself) is 1%. Regarding the camera we demonstrate stability in steady state conditions at the level of 32.5 ppm. Homogeneity in the response is below 1% RMS across the entire sensor area. Quantum efficiency stays above 50% in most of the visible range, peaking well above 80% between 440 nm and 570 nm. Differential nonlinearities at the level of 1% are detected. A simple two-parameter model is proposed to mitigate the effect and found to adequately correct the shape of the PTC on half the numerical scale. No significant deviations from integral linearity were detected in our limited test. Static and dynamical correlations between pixels are low, making the device likely suitable for galaxy shape measurements.
Measurements of the growth rate of structures at
z
< 0.1 with peculiar velocity surveys have the potential of testing the validity of general relativity on cosmic scales. In this work, we present ...growth-rate measurements from realistic simulated sets of type-Ia supernovae (SNe Ia) from the Zwicky Transient Facility (ZTF). We describe our simulation methodology, the light-curve fitting, and peculiar velocity estimation. Using the maximum likelihood method, we derived constraints on
fσ
8
using only ZTF SN Ia peculiar velocities. We carefully tested the method and we quantified biases due to selection effects (photometric detection, spectroscopic follow-up for typing) on several independent realizations. We simulated the equivalent of 6 years of ZTF data, and considering an unbiased spectroscopically typed sample at
z
< 0.06, we obtained unbiased estimates of
fσ
8
with an average uncertainty of 19% precision. We also investigated the information gain in applying bias correction methods. Our results validate our framework, which can be used on real ZTF data.
For dentists, leadership is often tied to the primary revenue generator for the business. The consummate leader in a dental practice is almost always working in the business and rarely on the ...business, knowing full well that working on the business is the seed that generates growth and advances the business. An extreme focus on business results has proven to be a significant cause for strife in organizations. It is important to recognize where good business results come from, and they don't come from putting in extra hours or double-booking the operatory. Truly outstanding results come from amazing customer experiences. When customers are amazed, they want more. When extraordinary teams focus on creating great patient experiences -- from the moment they initiate contact with the office through the billing cycle -- that's the catalyst to create customer loyalty.
The dental industry is experiencing a mass migration and consolidation of practices as a generation leaves the workforce. Ten years ago, as the baby boomer generation started to enter retirement ago, ...the financial crash delayed those retirements. It is predicted that 20,000 practices will be vacated in the next two to three years. A mere 6,500 or so dental students graduate each year. While many dentists are buying up multiple practices, they must consider how those businesses will remain viable when the selling producers exit. Increased competition and decreased reimbursement necessitate a new model to maintain solvency and, ultimately, success. When business owners evaluate their options for the future, they must first be clear about two things -- what their current state of business is, and what they hope to shape this business into during the next few years. Forecasting beyond that window could help craft a vision for the business, but it will not aid in creating the strategic goals and waypoints to propel a business toward that vision.
Replication protein A (RPA) is a heterotrimeric, multidomain, single-stranded DNA binding protein that is essential for DNA replication, repair, and recombination. Crystallographic and NMR studies on ...RPA protein fragments have provided structures for all domains; however, intact heterotrimeric RPA has resisted crystallization, and a complete protein structure has not yet been described. In this study, computational methods and experimental reactivity information (MRAN) were used to model the complete structure of RPA. To accomplish this, models of RPA’s globular domains and its domain-linking regions were docked in various orders. We also determined rates of proteolytic cleavage and amino acid side chain chemical modifications in native, solution state RPA. These experimental data were used to select alternate modeling intermediates and final structural models, leading to a single model most consistent with our results. Using molecular dynamics simulations and multiple rounds of simulated annealing, we then relaxed this structural model and examined its flexibility. The family of resultant models is consistent with other, previously published, critical lines of evidence and with experimental reactivity data presented herein.
Many dentists today are choosing to build their own group practices. This article will review critical aspects of building multiple practices. The fastest means of growth for a dental group is the ...acquisition of existing practices. The acquisition process starts with clear, identified goals. Creating the economies of scale necessary to increase profitability through expansion requires a centralized software platform. One of the most immediate benefits of centralization is the ability to pull the billing activities out of the front office. When this is done, the staff can focus on patient interaction, case presentation, and other activities that directly impact production. The dental team is your greatest asset in growing your practice multiple. Start by creating a production-based mindset with a compensation program that rewards the team for hitting goals.
In 1950, more than 99% of dentists were solo practitioners. Today, the ADA places that number closer to 60%, and trends indicate that number will continue to fall. While many dentists are choosing a ...dental service organization or another form of "corporate dentistry," it seems many are choosing to build their own group practices. Over the next four months, the author will explore the four phases of expanding your practice to multiple locations, starting with the most critical: planning. The planning phase includes three stages: 1. clarifying your vision and mission, 2. drafting a business plan, and 3. developing the leadership and communication skills to implement your plan.
Your practice lease is one of the most important documents you'll sign in your professional life. To ensure that your lease does not impact your ability to grow your practice or provide the best ...possible care for your patients, there are several things you should do: 1. Note the expiration date of your lease. 2. Do not go month to month with your lease. 3. Keep your future plans private for as long as possible, within the terms of your current lease. 4. Do not rely on the broker to negotiate the terms of your lease. 5. Do not accept any addendums to your lease without having them reviewed by a lease professional (not a broker).
Right now, dental graduates have record level of debt. The retirement boom is forecasted to outpace the rate of new dental graduates for the next six to 10 years. Preferred provider organizations ...have created intense pressure for practice profitability. Dental consumer spending, which began to slow during the early 2000s, is expected to continue to lag for the next three to five years. And dentists' earnings remain sluggish. More than 17% of doctors now work in group practices, a critical mass that could lead to permanent change, according to Malcolm Gladwell in his book, The Tipping Point: How Little Things Can Make a Big Difference. Before making any significant changes, thoroughly research all of your options. One of the most popular choices, a management services organization, generally operates in return for 10% of gross production.
Undo is a command that users rely on in most software applications. Its importance in multi-user CAD is no different. However, due to its unique nature, users may have different expectations ...regarding how undo should behave. This research seeks to better understand users' expectations regarding undo in multi-user CAD by having users participate in collaborative design exercises and then asking them how they would expect undo to behave. In addition, users participated in a survey in which they watched 8 videos showing users interacting within multi-user CAD and were then asked about how they would want undo to behave. Based on these findings, various recommendations are made for how undo ought to be implemented in multi-user CAD. These include recommendations regarding the user experience/user interface as well as proposing an equation that seeks to quantify whether a user expects to share an undo stack with another user or if they should only be able to undo their own actions.
