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Presents the comment of Rong-jue Wei concerning the omission of acoustics and related subjects in the curriculum of a physics major. China/United States Physics Examination and Application (CUSPEA); The lack of acoustics courses; Acoustics as a requisite part of basic physics training.

In the United States, obesity and severe obesity in children and adolescents are defined using threshold values from the 2000 Centers for Disease Control and Prevention (CDC) sex-specific body mass index (BMI)- for-age growth charts. BMI z-scores and percentiles from the 2000 CDC BMI-for-age growth charts are also used to monitor children's weight status over time and to evaluate obesity treatments. Parameters to calculate percentiles and corresponding z-scores (BMIz) were derived from selected percentiles between the 3rd and 97th. Use of the BMI-for-age growth charts for children and adolescents with extremely high BMI requires extrapolation beyond the 97th percentile, which leads to compression of BMIz values into a very narrow range and is not recommended. This report evaluates eight alternative BMI metrics for monitoring weight status in children and adolescents with extremely high BMI., (All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.)

Background: In the United States (US), urinary tract infections (UTI) lead to more than 10 million office visits each year. Temperature and season are potentially important risk factors for UTI, particularly in the context of climate change., Methods: We examined the relationship between ambient temperature and outpatient UTI diagnoses among patients followed from 2015 to 2017 in two California healthcare systems: Kaiser Permanente Southern California (KPSC) and Sutter Health in Northern California. We identified UTI diagnoses in adult patients using diagnostic codes and laboratory records from electronic health records. We abstracted patient age, sex, season of diagnosis, and linked community-level Index of Concentration at the Extremes (ICE-I, a measure of wealth and poverty concentration) based on residential address. Daily county-level average ambient temperature was assembled from the Parameter-elevation Regressions on Independent Slopes Model (PRISM). We implemented distributed lag nonlinear models (DLNM) to assess the association between UTI and lagged daily temperatures. Main analyses were confined to women. In secondary analyses, we stratified by season, healthcare system, and community-level ICE-I., Results: We observed 787,186 UTI cases (89% among women). We observed a threshold association between ambient temperature and UTI among women: an increase in daily temperature from the 5th percentile (6.0 ˚C) to the mean (16.2 ˚C) was associated with a 3.2% (95% CI: 2.4, 3.9%) increase in same-day UTI diagnosis rate, whereas an increase from the mean to 95th percentile was associated with no change in UTI risk (0.0%, 95% CI: -0.7, 0.6%). In secondary analyses, we observed the clearest monotonic increase in the rate of UTI diagnosis with higher temperatures in the fall. Associations did not differ meaningfully by healthcare system or community-level ICE-I. Results were robust to alternate model specifications., Discussion: Increasing temperature was related to higher rate of outpatient UTI, particularly in the shoulder seasons (spring, autumn)., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background Previous reports suggest that the use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) may upregulate angiotensin-converting enzyme 2 receptors and increase severe acute respiratory syndrome coronavirus 2 infectivity. We evaluated the association between ACEI or ARB use and coronavirus disease 2019 (COVID-19) infection among patients with hypertension. Methods and Results We identified patients with hypertension as of March 1, 2020 (index date) from Kaiser Permanente Southern California. Patients who received ACEIs, ARBs, calcium channel blockers, beta blockers, thiazide diuretics (TD), or no therapy were identified using outpatient pharmacy data covering the index date. Outcome of interest was a positive reverse transcription polymerase chain reaction test for COVID-19 between March 1 and May 6, 2020. Patient sociodemographic and clinical characteristics were identified within 1 year preindex date. Among 824 650 patients with hypertension, 16 898 (2.0%) were tested for COVID-19. Of those tested, 1794 (10.6%) had a positive result. Overall, exposure to ACEIs or ARBs was not statistically significantly associated with COVID-19 infection after propensity score adjustment (odds ratio [OR], 1.06; 95% CI, 0.90-1.25) for ACEIs versus calcium channel blockers/beta blockers/TD; OR, 1.10; 95% CI, 0.91-1.31 for ARBs versus calcium channel blockers/beta blockers/TD). The associations between ACEI use and COVID-19 infection varied in different age groups ( P -interaction=0.03). ACEI use was associated with lower odds of COVID-19 among those aged ≥85 years (OR, 0.30; 95% CI, 0.12-0.77). Use of no antihypertensive medication was significantly associated with increased odds of COVID-19 infection compared with calcium channel blockers/beta blockers/TD (OR, 1.32; 95% CI, 1.11-1.56). Conclusions Neither ACEI nor ARB use was associated with increased likelihood of COVID-19 infection. Decreased odds of COVID-19 infection among adults ≥85 years using ACEIs warrants further investigation.

Background: The 2000 CDC growth charts are based on national data collected between 1963 and 1994 and include a set of selected percentiles between the 3 rd and 97 th and LMS parameters that can be used to obtain other percentiles and associated z-scores. Obesity is defined as a sex- and age-specific body mass index (BMI) at or above the 95 th percentile. Extrapolating beyond the 97 th percentile is not recommended and leads to compressed z-score values., Aim: This study attempts to overcome this limitation by constructing a new method for calculating BMI distributions above the 95 th percentile using an extended reference population., Subjects and Methods: Data from youth at or above the 95 th percentile of BMI-for-age in national surveys between 1963 and 2016 were modelled as half-normal distributions. Scale parameters for these distributions were estimated at each sex-specific 6-month age-interval, from 24 to 239 months, and then smoothed as a function of age using regression procedures., Results: The modelled distributions above the 95 th percentile can be used to calculate percentiles and non-compressed z-scores for extreme BMI values among youth., Conclusion: This method can be used, in conjunction with the current CDC BMI-for-age growth charts, to track extreme values of BMI among youth.

Background: Lipid screening determines eligibility for statins and other cardiovascular risk reduction interventions., Objective: To examine trends in lipid screening among adults aged ≥20 years in a large, multiethnic, integrated health care delivery system in southern California., Methods: Temporal trends in lipid screening were examined from 2009 to 2015 with an index date of September 30 of each year. Lipid screening was defined as the proportion of eligible members each year who (a) had ever been screened among those aged 20-39 years and (b) had been screened in the previous 6 years for those aged ≥ 40 years. Trends were analyzed by age, gender, and the presence of atherosclerotic cardiovascular disease (ASCVD) or diabetes without ASCVD status., Results: More than 2 million individuals were included each year: 5%-6% had ASCVD (includes those with diabetes), 7%-8% had diabetes without ASCVD, and 87% had neither condition. Among the entire population, lipid screening increased from 79.8% in 2009 to 82.6% in 2015 (P < 0.0001). Among those with ASCVD or diabetes, lipid screening was 99% across all years. Among those without ASCVD or DM, screening increased from 76.9% in 2009 to 80.0% in 2015 (P < 0.0001), with higher screening among women compared with men and lower screening among individuals younger than 55 years., Conclusions: Consistently high rates of lipid screening were observed among individuals with ASCVD or diabetes. In individuals without these conditions, screening increased over time. However, there is room to further increase screening rates in adults younger than 55 years., Disclosures: This manuscript and research work was supported by a contractual agreement between the Southern California Permanente Medical Group and Regeneron Pharmaceuticals and Sanofi U.S. Researchers from Regeneron and Sanofi collaborated on the study design, interpretation of data, and writing of the manuscript. Ling Grant, Harrison, Chang, Hsu, Cheetham, Wei, and Reynolds are employed by Kaiser Permanente Southern California. Scott is employed by Southern California Permanente Medical Group. Boklage is employed by Regeneron, and Romo-LeTourneau is employed by Sanofi. Preliminary results from this study were presented at the American Heart Association Scientific Sessions; November 12-16, 2016; New Orleans, LA.

In US states with small subpopulations, the observed mortality rates are often zero, particularly among young ages. Because in life tables, death rates are reported mostly on a log scale, zero mortality rates are problematic. To overcome the observed zero death rates problem, appropriate probability models are used. Using these models, observed zero mortality rates are replaced by the corresponding expected values. This enables logarithmic transformations and, in some cases, the fitting of the eight-parameter Heligman-Pollard model to produce mortality estimates for ages 0-130 years, a procedure illustrated in terms of mortality data from several states., (Copyright © 2014 John Wiley & Sons, Ltd.)

Objective: This report, following publication of the national life tables (1,2) for 1999-2001, presents state-specific life tables for the 50 states and District of Columbia by race (white and black) and sex. These tables are the most recent in a series of decennial life tables for the United States., Methods: Data used to prepare these state-specific life tables include population counts by age on the census date of April 1, 2000; deaths occurring in the 3-year period of 1999-2001; and counts of U.S. resident births during 1997-2001. Methods for calculating the life tables were modified from the previous decennial life tables to automate the smoothing of age-specific mortality data and to allow for the estimation of life tables for smaller population subgroups, which often had insufficient data available to estimate reliable life tables under the previous method. The current method allows for the estimation of life tables for the black population in six states, which were never previously published due to small numbers of deaths. Standard errors for estimating life expectancy and probability of dying are also presented in this report., Results: Among the 50 states, Hawaii had the highest life expectancy at birth during the 1999-2001 period at 80.23 years, and Mississippi had the lowest life expectancy at 73.88 years. Life expectancy for the District of Columbia was even lower at 73.09 years. State-specific life expectancy at birth improved from the previous decennial period (1989-1991) for all states and the District of Columbia. Life expectancy at age 65 ranged from 20.42 years in Hawaii to 16.61 years in Kentucky. Life expectancy at age 65 also improved for all states except Kentucky.

This paper explores three issues related to the 2000 Centers for Disease Control and Prevention growth charts. First, it clarifies the methods that were used to create the charts as it has become apparent that the smoothing techniques have been somewhat misunderstood. The techniques included smoothing-selected percentiles between and including the 3rd and 97th percentiles and then approximating these smoothed curves using a procedure to provide the transformation parameters, lambda, mu, and sigma. Only the selected percentiles were used in this process due to small sample sizes beyond these percentiles. Second, given the concern that the infant charts were created with relatively few data points in the first few months of life, it compares the original observed percentiles with percentiles that include newly available US national data for the first few months of life. Third, it discusses the issues that arise if a 99th percentile is extrapolated based on the lambda, mu, and sigma parameters. The 99th percentile of the body mass index-for-age chart has been recommended to identify extremely obese children, yet the 97th percentile is the highest available percentile on the Centers for Disease Control and Prevention growth charts., (Copyright (c) 2010 S. Karger AG, Basel.)

Background: The 2000 Centers for Disease Control and Prevention (CDC) growth charts included lambda-mu-sigma (LMS) parameters intended to calculate smoothed percentiles from only the 3rd to the 97th percentile., Objective: The objective was to evaluate different approaches to describing more extreme values of body mass index (BMI)-for-age by using simple functions of the CDC growth charts., Design: Empirical data for the 99th and the 1st percentiles of BMI-for-age were calculated from the data set used to construct the growth charts and were compared with estimates extrapolated from the CDC-supplied LMS parameters and to various functions of other smoothed percentiles. A set of reestimated LMS parameters that incorporated a smoothed 99th percentile were also evaluated., Results: Extreme percentiles extrapolated from the CDC-supplied LMS parameters did not match well to the empirical data for the 99th percentile. A better fit to the empirical data was obtained by using 120% of the smoothed 95th percentile. The empirical first percentile was reasonably well approximated by extrapolations from the LMS values. The reestimated LMS parameters had several drawbacks and no clear advantages., Conclusions: Several approximations can be used to describe extreme high values of BMI-for-age with the use of the CDC growth charts. Extrapolation from the CDC-supplied LMS parameters does not provide a good fit to the empirical 99th percentile values. Simple approximations to high values as percentages of the existing smoothed percentiles have some practical advantages over imputation of very high percentiles. The expression of high BMI values as a percentage of the 95th percentile can provide a flexible approach to describing and tracking heavier children.

Objectives: This report describes the methodology used in the preparation of the 1999-2001 decennial life tables for the United States., Methods: Data used to prepare these life tables include population data by age on the census date April 1, 2000; deaths occurring in the 3-year period 1999-2001 classified by age at death; births for each of the years 1997-2001; and Medicare data for ages 66-100 years from the years 1999-2001. Methods that were kept the same as those of previous decennial tables include data sources used in constructing tables, the preliminary adjustment for misreported ages, the smoothing techniques for vital statistics and census data, and the calculations of death rates in different age groups. Two significant changes were made to the methodology used to estimate mortality for the populations aged 66 years and over. First, Medicare data were used to supplement vital statistics (number of deaths) and census data (population estimates) starting at age 66 years instead of age 85 years as was done in the estimation of previous U.S. decennial life tables. Second, smoothing and extrapolation of death rates for ages 66-109 was performed using a mathematical model given by Heligman and Pollard, instead of a Whittaker-Henderson Type B formula or modified Gompertz method.

Objectives: This report presents period life tables for the United States based on age-specific death rates for the period 1999-2001. These tables are the most recent in a 100-year series of decennial life tables for the United States., Methods: This report presents complete life tables by age, race (white and black), and sex. Also presented are standard errors of the probability of dying and life expectancy. The data used to prepare these life tables are population estimates based on the 2000 decennial census, deaths occurring in the United States to U.S. residents in the 3 years 1999-2001, counts of U.S. resident births in the years 1997-2001, and population and death counts from the Medicare program for years 1999-2001., Results: In 1999-2001, life expectancy at birth was 76.83 years for the total U.S. population, representing an increase of 27.59 years from a life expectancy of 49.24 years in 1900. Between 1900 and 2000, life expectancy increased by 40.08 years for black females (from 35.04 to 75.12), by 35.54 years for black males (from 32.54 to 68.08), by 28.89 years for white females (from 51.08 to 79.97), and by 26.51 years for white males (from 48.23 to 74.74).

Purpose: We investigated whether the substance use problems of excessive alcohol consumption and marijuana use, firearm availability, depressive symptoms, and mental health service utilization, differed among white and African American suicide decedents compared with natural cause-of-death decedents., Methods: The subjects were a representative sample of 22,957 deceased individuals aged 15 years or older from the 1993 US National Mortality Followback Survey (NMFS). A matched case-control study was constructed for suicide decedents aged 15 to 64 years, with natural death controls frequency matched to cases by age and gender. Conditional logistic regression analysis was used to examine the associations of risk factors with suicide by race., Results: When compared with natural causes of death, suicide deaths among white decedents were associated with use of mental health services, heavy drinking, marijuana use, depression symptoms, and firearm availability. Suicides by African American decedents were associated only with use of mental health services, marijuana, and firearm availability. The interaction of mental health service use and marijuana use was significant only for white suicide decedents., Conclusion: This study contributes to the limited understanding of how risk factors unique to suicide differ, and possibly interact, among African American and white decedents. Similarities and differences in risk factors should be considered in suicide prevention planning efforts.

Objectives: This report provides detailed information on how the 2000 Centers for Disease Control and Prevention (CDC) growth charts for the United States were developed, expanding upon the report that accompanied the initial release of the charts in 2000., Methods: The growth charts were developed with data from five national health examination surveys and limited supplemental data. Smoothed percentile curves were developed in two stages. In the first stage, selected empirical percentiles were smoothed with a variety of parametric and nonparametric procedures. In the second stage, parameters were created to obtain the final curves, additional percentiles and z-scores. The revised charts were evaluated using statistical and graphical measures., Results: The 1977 National Center for Health Statistics (NCHS) growth charts were revised for infants (birth to 36 months) and older children (2 to 20 years). New body mass index-for-age (BMI-for-age) charts were created. Use of national data improved the transition from the infant charts to those for older children. The evaluation of the charts found no large or systematic differences between the smoothed percentiles and the empirical data., Conclusion: The 2000 CDC growth charts were developed with improved data and statistical procedures. Health care providers now have an instrument for growth screening that better represents the racial-ethnic diversity and combination of breast- and formula-feeding in the United States. It is recommended that these charts replace the 1977 NCHS charts when assessing the size and growth patterns of infants, children, and adolescents.

Background: The 2000 Centers for Disease Control and Prevention growth charts for the United States include population reference data for body mass index (BMI)-for-age (ages 2-19 y) and weight-for-stature (from 77 to 121 cm). For younger children, either set of reference data could be used., Objective: The objective of this study was to compare BMI-for-age with weight-for-stature., Design: We used data for 4348 children (aged 2-5 y) from the third National Health and Nutrition Examination Survey. Weight-for-stature and BMI-for-age percentiles were calculated for each child. The 10th and 85th percentiles of weight-for-stature at selected ages were also reexpressed as BMI-for-age percentiles., Results: More than 63% of children had lower weight-for-stature than BMI-for-age percentiles. Children were more likely to be classified as < or = 10th percentile by weight-for-stature than by BMI-for-age, but less likely to be classified as > or = 85th percentile. Differences in classification by the 2 measures varied with age and stature and were greater for shorter children. The 10th and 85th percentiles of weight-for-stature corresponded to BMI-for-age percentiles from the 3rd to the 21st percentile and from the 74th to the 92nd percentile, respectively, depending on age and stature., Conclusions: Weight-for-stature is easier to use than BMI-for-age. However, BMI-for-age captures changes in the weight-height relation with age and can be used continuously up to the age of 20 y. BMI-for-age is recommended in most situations. BMI-for-age and weight-for-stature will not give identical results and are not interchangeable.

Objective: To present a clinical version of the 2000 Centers for Disease Control and Prevention (CDC) growth charts and to compare them with the previous version, the 1977 National Center for Health Statistics (NCHS) growth charts., Methods: The 2000 CDC percentile curves were developed in 2 stages. In the first stage, the empirical percentiles were smoothed by a variety of parametric and nonparametric procedures. To obtain corresponding percentiles and z scores, we approximated the smoothed percentiles using a modified LMS estimation procedure in the second stage. The charts include of a set of curves for infants, birth to 36 months of age, and a set for children and adolescents, 2 to 20 years of age., Results: The charts represent a cross-section of children who live in the United States; breastfed infants are represented on the basis of their distribution in the US population. The 2000 CDC growth charts more closely match the national distribution of birth weights than did the 1977 NCHS growth charts, and the disjunction between weight-for-length and weight-for-stature or length-for-age and stature-for-age found in the 1977 charts has been corrected. Moreover, the 2000 CDC growth charts can be used to obtain both percentiles and z scores. Finally, body mass index-for-age charts are available for children and adolescents 2 to 20 years of age., Conclusion: The 2000 CDC growth charts are recommended for use in the United States. Pediatric clinics should make the transition from the 1977 NCHS to the 2000 CDC charts for routine monitoring of growth in infants, children, and adolescents.