Effects of hypochlorous acid mouthwash on salivary bacteria including Staphylococcus aureus in patients with periodontal disease: a randomized controlled trial.

BACKGROUND: The effects of a low concentration of hypochlorous acid (HOCl) mouthwash on salivary bacteria remained unclear. We aimed to evaluate the antibacterial effects of 100 ppm HOCl mouthwash on salivary bacteria, including Staphylococcus aureus (S. aureus), in patients with periodontal disease (PD). METHODS: Patients with PD were randomized into mouthwash-only (MW, n = 26) and mouthwash with periodontal flosser (MWPF, n = 27) groups. Patients without PD were selected for the control group (n = 30). S. aureus culture and saliva samples (before and after the intervention) were collected for bacterial DNA extraction. A real-time polymerase chain reaction assay and serial dilutions of S. aureus culture and saliva samples were used to measure the salivary bacteria total count (SBTC) and confirm the antibacterial effects of the mouthwash using S. aureus. RESULTS: No significant difference in demographic data was observed among the three groups. Before the intervention, the baseline SBTC of the MW and MWPF groups was significantly higher than that of the control group. After the mouthwash rinses, the SBTC data significantly changed in the MW and MWPF groups only (by 62.4% and 77.4%, respectively). After the base-2 log-transformation of the SBTC data, a similar trend was observed. Linear regression revealed that baseline SBTC and the MWPF intervention significantly affected SBTC reduction percentage by volume. After incubation with 10% (v/v) of mouthwash, the survival rates of 106 and 107 colony-forming units/mL of S. aureus were 0.51% ± 0.06% and 1.42% ± 0.37%, respectively. CONCLUSIONS: These study results indicated that 100 ppm HOCl mouthwash treatment could effectively reduce SBTC in patients with PD and the abundance of S. aureus. It provides that the HOCl mouthwash can be an option for individuals to help control SBTC, especially in patients with PD. TRIAL REGISTRATION: The study protocol was approved by the Institutional Review Board of Kaohsiung Medical University Hospital (KMUHIRB-F(I)-20200042) on 20/03/2020 and retrospectively registered at ClinicalTrial.gov (NCT05372835) on 13/05/2022.

Estimation of Greenhouse Lettuce Growth Indices Based on a Two-Stage CNN Using RGB-D Images.

Growth indices can quantify crop productivity and establish optimal environmental, nutritional, and irrigation control strategies. A convolutional neural network (CNN)-based model is presented for estimating various growth indices (i.e., fresh weight, dry weight, height, leaf area, and diameter) of four varieties of greenhouse lettuce using red, green, blue, and depth (RGB-D) data obtained using a stereo camera. Data from an online autonomous greenhouse challenge (Wageningen University, June 2021) were employed in this study. The data were collected using an Intel RealSense D415 camera. The developed model has a two-stage CNN architecture based on ResNet50V2 layers. The developed model provided coefficients of determination from 0.88 to 0.95, with normalized root mean square errors of 6.09%, 6.30%, 7.65%, 7.92%, and 5.62% for fresh weight, dry weight, height, diameter, and leaf area, respectively, on unknown lettuce images. Using red, green, blue (RGB) and depth data employed in the CNN improved the determination accuracy for all five lettuce growth indices due to the ability of the stereo camera to extract height information on lettuce. The average time for processing each lettuce image using the developed CNN model run on a Jetson SUB mini-PC with a Jetson Xavier NX was 0.83 s, indicating the potential for the model in fast real-time sensing of lettuce growth indices.

Experimental design of a simple medium for the bioluminescence of Aliivibrio fischeri and mathematical modelling for growth estimation.

Increasing numbers of studies are using Aliivibrio fischeri (A. fischeri), a marine bioluminescent bacterium as a model, however the culture medium used for its growth are complex and expensive. The objectives of this study were: (1) to evaluate the effect of yeast extract, tryptone, and NaCl to select a simple and inexpensive culture medium suitable for A. fischeri growth and bioluminescence induction; and (2) to compare the performance of mathematical models to predict the growth of A. fischeri. A fractional factorial design was performed to evaluate the effect of yeast extract, tryptone, and sodium chloride on the luminescence of A. fischeri. The result showed that sodium chloride is the most important factor, congruent with its inducer role in bioluminescence. The best medium for bioluminescence induction was selected through an optimization plot, this medium is inexpensive, and generates the same luminescence as commercial formulations. The estimation of A. fischeri growth at OD600 measurement was statistically analyzed. All evaluated models fitted the data adequately (r2  > 0.96). The nonlinear models Gompertz, Richards and logistic provided a lower variation and a better fit of the growth estimation (r2 >0.99), showing that these mathematical models can be used for the accurate growth prediction of A. fischeri.

COVID-DAI: A novel framework for COVID-19 detection and infection growth estimation using computed tomography images.

The COVID-19 pandemic is spreading at a fast pace around the world and has a high mortality rate. Since there is no proper treatment of COVID-19 and its multiple variants, for example, Alpha, Beta, Gamma, and Delta, being more infectious in nature are affecting millions of people, further complicates the detection process, so, victims are at the risk of death. However, timely and accurate diagnosis of this deadly virus can not only save the patients from life loss but can also prevent them from the complex treatment procedures. Accurate segmentation and classification of COVID-19 is a tedious job due to the extensive variations in its shape and similarity with other diseases like Pneumonia. Furthermore, the existing techniques have hardly focused on the infection growth estimation over time which can assist the doctors to better analyze the condition of COVID-19-affected patients. In this work, we tried to overcome the shortcomings of existing studies by proposing a model capable of segmenting, classifying the COVID-19 from computed tomography images, and predicting its behavior over a certain period. The framework comprises four main steps: (i) data preparation, (ii) segmentation, (iii) infection growth estimation, and (iv) classification. After performing the pre-processing step, we introduced the DenseNet-77 based UNET approach. Initially, the DenseNet-77 is used at the Encoder module of the UNET model to calculate the deep keypoints which are later segmented to show the coronavirus region. Then, the infection growth estimation of COVID-19 per patient is estimated using the blob analysis. Finally, we employed the DenseNet-77 framework as an end-to-end network to classify the input images into three classes namely healthy, COVID-19-affected, and pneumonia images. We evaluated the proposed model over the COVID-19-20 and COVIDx CT-2A datasets for segmentation and classification tasks, respectively. Furthermore, unlike existing techniques, we performed a cross-dataset evaluation to show the generalization ability of our method. The quantitative and qualitative evaluation confirms that our method is robust to both COVID-19 segmentation and classification and can accurately predict the infection growth in a certain time frame. RESEARCH HIGHLIGHTS: We present an improved UNET framework with a DenseNet-77-based encoder for deep keypoints extraction to enhance the identification and segmentation performance of the coronavirus while reducing the computational complexity as well. We propose a computationally robust approach for COVID-19 infection segmentation due to fewer model parameters. Robust segmentation of COVID-19 due to accurate feature computation power of DenseNet-77. A module is introduced to predict the infection growth of COVID-19 for a patient to analyze its severity over time. We present such a framework that can effectively classify the samples into several classes, that is, COVID-19, Pneumonia, and healthy samples. Rigorous experimentation was performed including the cross-dataset evaluation to prove the efficacy of the presented technique.

Growth estimation of the larger foraminifer Heterostegina depressa by means of population dynamics.

In Heterostegina depressa, the flagship species of laboratory investigations of larger benthic foraminifera (LBF) since the 70's, the timing of reproduction, longevity and natural chamber building rates are still understudied. A recently developed method, the natural laboratory (sensu Hohenegger), has been applied on H. depressa populations from Sesoko Jima, NW Okinawa, Japan. An averaged chamber building rate and longevity of H. depressa were calculated based on 17 monthly samplings at fixed stations. All samples were collected at 20 and 50 m water depths using SCUBA. Live populations were dried and investigated by microCT. The monthly frequency distributions of chamber numbers and test diameters have been decomposed in normally distributed components. For each month, mean and standard deviations of the components were used to calculate the maximum chamber number and maximum test diameter. Based on these values, the natural chamber building rate (CBR) or diameter increase rate (DIR) could be estimated using the Michaelis-Menten function. CBR and DIR were inverted to estimate the 'birthdate' of all investigated individuals. Based on frequencies of these 'birthdates', main reproduction events could be detected and compared to the reproduction timing of other subtropical and tropical LBF taxa. Furthermore, peaks in reproduction could be linked to monsoon wet seasons (="rainy seasons") and winter rains.

An evaluation of a special-type vital statistics registration system in a rural area of Nigeria.

PIP: An alternative system for registering birth and deaths, instituted in 1964 in Igbo-Ora, a rural Nigerian town of than conventional registration procedures. In the alternative system, 6 individuals were hired and expected to visit all the households in the town every 2 weeks and to record any deaths or births which had occurred during the previous 2 weeks. The system has been in operation for 10 years. The completeness of the birth and death registration by the home visitors was assessed for 1974. Birth registrations were at least 95% complete and death registrations were approximately 87% complete; however, for children under 1 year of age death registrations were only 49% complete. It was suggested that death registrations for those under 1 year of age could be improved if the health visitors would specifically inquire 1) about the health status of each newborn at every visit during the 1st year and 2) about the outcome of each pregnancy observed by the visitors. The use of home visitors, although more costly, was considerably more accurate than the conventional system in which individuals were expected to register births and deaths themselves. The evaluation procedures included a complete household survey of the town and the use of techniques developed by Brass and by Fargues and Courbage for correcting death registrations. Tables show 1) estimated population figures and crude birth and death rates for the town for 1964-1974; 2) estimated gross reproduction rate for 1974; and 3) crude birth and death rates for 1974 estimated by using various analytical techniques.^ieng

Asymptotic worst-case mixing in simple demographic models of HIV/AIDS.

The majority of published modeling work regarding the impact of mixing patterns among subgroups on the spread of HIV infection assumes either that the overall population size remains constant, the aggregate immigration to the population occurs at a constant annual rate, or that no immigration occurs and the population in question declines due to HIV or other causes. In this paper, immigration rates are modeled as simple functions of population size and may be interpreted as aggregate birth rates. This assumption implies asymptotic exponential growth in the disease-free population as long as per capita birth rates exceed per capita mortality rates. The introduction of HIV infection to such a population may change this situation, and the asymptotic population growth rate can be reduced substantially as a result. The specific manner in which this occurs depends in part upon difficult to observe mixing patterns among those with different sexual activity rates. Rather than attempting to explicitly model a variety of mixing patterns, a bound on the impact of worst-case mixing is produced, where "worst case" refers to the mixing pattern that maximizes the asymptotic prevalence of infection, which is equivalent to minimizing the asymptotic population growth rate. These new techniques are illustrated with a numerical example.

Our population predicament: a new look.

PIP: Issued to mark the Population Reference Bureau's 50th anniversary, this issue updates the story of world population presented in its popular predecessor of 1971, "Man's Population Predicament." Estimated at 1/2 billion in 1650, world population reached about 2 billion in 1930, 4 billion in 1975, and is projected to be about 6 billion in 2000. Most of today's rapid growth is occurring among the 3/4 of the world's peoples living in less developed countries where the post-World War II gap between high birth rates and falling death rates has only recently begun to narrow. This growth, coupled with high consumption in developing countries, is putting tremendous pressures on the Earth's resources, environment, and social fabric. New evidence on Europe's population transition and from China, Indonesia, and Thailand in the 1970s suggests that well-designed family planning programs can speed fertility decline but rapid worldwide attainment of replacement level fertility will also require special development efforts and measures that go beyond family planning. Current projections of the world's ultimate peak population range from 8 billion in the mid 21st century to 11 billion in about 2125, depending on when replacement-level fertility is reached. China's drive for a drastic birth rate reduction and the oil crisis might change fertility behavior more rapidly than most demographers have heretofore thought likely.^ieng

America's baby boom generation: the fateful bulge.

PIP: From 1955-64 nearly 42 million births occurred in the U.S., an unprecedented expansion. The roots of the baby boom lie in the universal rush to early marriage and favorable economic climate for the relatively scarce young men born of the Depression cohort. The impact of the boom interrupted a century-long fertility decline. Pro-marriage, pronatalist norms were revived by the Depression cohort who formed families of at least 2 children or more. During the 1960-70's schools, colleges, and universities were built to accomodate the boom and are now excessive for the baby bust cohort. Unemployment and crime rates rose and fell with the passing of the boom babies through late adolescence and early adulthood. In the 1980's, boom babies will be aged 20-30. Demands for housing will be high. Annual birth numbers will increase even if the rate of childbearing hovers below replacement level at about 1.8 per woman. Per capita earnings and overall labor productivity should improve as the boom baby cohort reaches middle age in the 1990s. However, chances for advancement will be fewer. As the cohort reaches retirement age, the over 65 population will double from 31 million in 2000 to almost 60 million in 2030. Although the burden will be somewhat offset by reduced proportions of under 18-year-olds, the ratio of active workers paying Social Security will fall drastically.^ieng

Canada's population: growth and dualism.

PIP: In Canada the current 1.3% population growth rate is causing some concern. Those concerned argue that such a rate of growth in combination with high levels of consumption could jeopardize the country's resource base and its comfortable style of living. Many Canadians are questioning high levels of immigration, for now that the fertility level is below replacement level, net immigration contributes substantially to population growth (over 1/3 in 1976). The growing proportion of non-Europeans among recent immigrants is causing resentment, and, in a tight job market, immigrants are regarded as threats to the World War 2 baby boom cohort who are now at working ages. The baby boom generation also puts stress on housing and health services, and it will increase the need for pension checks as it ages. Although French fertility is no longer high and immigration is no longer dominated by the British, the French group's 200-year struggle to preserve its identity continues on in the current effort of the Quebec government to enforce the use of French language by law within that province. Geography and climate dictate another demographic fact that divides the country and pervades its history. In addition to intense regionalism, uneven population distribution is responsible for 2 other concerns: the rapid growth of several already large cities and depopulation of many small communities. Focus in this discussion is on Canada's population growth in the past and as projected for the future, historical and current fertility, mortality and immigration trends, the search for a new immigration policy, the impact of the baby boom generation on the population's age structure and the problems this creates, and recent shifts in population distribution and in the country's ethnic and linguistic makeup. The population policy proposals evolved thus far involve to a great extent the use of immigration as a lever for achieving given population objectives.^ieng

World population projections: alternative paths to zero growth.

PIP: This article discusses Frejka's analysis of alternative paths to zero population growth. A net reproduction rate (NRR) of 1 is a vital step in reaching zero growth, but because of age distribution variances, it does not necessarily represent zero growth. The projections described here include: 1)the immediate path of achieving NRR of 1 in 1970-1975: 2)rapid path of an NRR of 1 in 2000-2005: and 3)slow path of NRR of 1 in 2040-2045. The population of the world in the year 2000 would be respectively: 5,700,000,000; 6,000000,000; and 7,000,000,000. Zero growth would be reached in 2000 for the immediate path; in 2100 with a population of 8,000,000,000 in the rapid path; and in 2045 with a population of 15,000,000,000. Individual projections are also given for several countries on different continents.^ieng

Declining world fertility: trends, causes, implications.

This Bulletin examines the evidence that the world's fertility has declined in recent years, the factors that appear to have accounted for the decline, and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world, the authors derive estimates which indicate that the world's total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975, thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors' projections, which are compared to similar projections from the World Bank, the United Nations, and the U.S. Bureau of the Census, indicate that, by the year 2000, less than 1/5 of the world's population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."

Indonesia's family planning story: success and challenge.

PIP: A historical overview and descriptions of family planning programs in Indonesia are presented. 85 million of the 135 million inhabitants of the Indonesian archipelago are concentrated on the island of Java, which comprises about 7% of the Indonesian land mass. The Dutch colonial government preferred a policy ("transmigration") which advocated the redistribution of population from Java to the other islands to relieve overpopulation. This policy was also advocated by President Sukarno after the Indonesian Revolution of 1940. The need for family planning was recognized by small groups, and official policy supported national family planning programs to replace transmigration programs only after Sukarno became president in 1966. The focus of the program was on Java and Bali, the 2 most populous islands. Local clinics became the locus for birth control efforts. Fieldworkers affiliated with the clinics were given the job of advocating birth control use door-to-door. Fieldworkers "incentive programs," area "target" (quota) programs, and "special drives" were organized to create new contraceptive "acceptors." A data reporting system and a research program increase the effectiveness of the family planning drive by ascertaining trends in contraceptive use which can determine where and how money and effort can best be applied. "Village Contraception Distribution Centers" bring the contraceptive means closer to the people than do the clinics. Figures from the years 1969-1977 show the great increase in acceptance of contraceptives by the inhabitants of the Java-Bali area. Steps are now being taken to alleviate the large monthly variations in the number of (often temporary) acceptors caused by the "target programs" and "special drives." The average acceptor is 27-years-old, has 2.6 children, has not finished primary school, and has a husband of low social status. Bali has shown the greatest success in family planning. It is a small island with a highly developed system of local clinics. The strong community structures on Bali encourage birth control use. Bali, which is predominantly Hindi, is more receptive to the IUD than Java, which is predominantly Muslim. In East Java, the authoritarian bureaucracy makes efficient use of its money. Central Java is making slow but steady progress in family planning. In West Java, fieldworkers are teamed with paramedics; there, door-to-door contraceptive supply was more effective than the clinic system. In many areas traditional methods, i.e., herbs, massage, total abstinence for long periods of time, etc., were favored. More educated women often do not use contraceptives for fear of side effects. The need for family planning on the outer Indonesian islands is not as great, but programs are being set under way. These programs are the beginning of an attempt to alleviate problems that could be encountered if Indonesia's population growth continues unchecked.^ieng

Postcensal estimates for local areas using current samples with census as the source of sampling frame.

"Two techniques for direct postcensal local area estimation are introduced in this paper. Compared with existing techniques for postcensal local area estimation, the proposed techniques are not subject to any bias due to the assumption of constancy of certain statistical relationships between the variable of interest and the symptomatic or associated variables established at a certain point in time (typically a census)." The author notes that "application of the proposed techniques calls for recognition of an integrated design approach at the early planning stage, incorporating considerations of survey designs for the census and the postcensal sample surveys, maintenance and upkeep of the census sampling frame, data analysis and local area estimation requirements simultaneously. When the current samples are continuous and overlap each other, a third technique for postcensal local area estimation is also proposed. An example illustrating these techniques in estimating postcensal district population in Hong Kong is given." (summary in FRE)

Population and development: is a consensus possible?

PIP: The debate concerning population growth and economic development cen ters on whether efforts should be specifically directed at reducing popu lation growth or on general economic and social development. Arguments supporting the former include 1) the position that unrestrained population growth is the principal cause of social problems; 2) the position that there is a demand for fertility control and thus provision of services is needed; 3) the human rights position that it is a fundamental right to determine family size, to have good health, and for women to control their own bodies; and 4) the population-programs-plus-d evelopment position. Positions against the need for special population programs include 1) the pronatalist position; 2) the revolutionary position; 3) the anticolonial and genocide position; 4) the position that the developed countries overconsume resources, which is more detrimental than the population growth; 5) the position that the problem is one of underemployment and that a proper economy can provide employment regardless of population size; 6) the position that the problem is one of distribution of the population, not of its size; 7) the position that fertility will decline when mortality declines and that provision of social security will lead to fertility declines; 8) the status-of-women position; 9) the religious-doctrine position; 10) the medical-risk-of-contraception position; 11) the holistic-development position; and 12) the social-justice position. A consensus position on population plus development programs which would include elements of the other positions seems to be the most logical means of formulating a program for action that would be acceptable to a majority of countries.^ieng

Population growth and economic development: the case of Mexico.

PIP: A review of events in Mexico since the publication in 1958 of Coale and Hoover's "Population Growth and Economic Development in Low Income Countries," in which they concluded that a low income country with high fertility would achieve better progress if it could reduce its fertility than if it did not do so. India and Mexico were the cases considered. Over the 20 years from 1955-75 the population of Mexico more than doubled, slightly exceeding Coale and Hoover's high projections. During that time Mexico saw substantial economic progress: a 72% increase in the proportion of primary school age children actually attending school; a 26% increase in literacy; an 89% increase in per capita income at constant prices; a 38% increase in the urban population; and a 27% rise in the average duration of life. These figures reveal the error of assuming that rapid population increase in a poor country leads inevitably to malnutrition, impoverishment, and social collapse, but also show that economic development does not automatically lead to a slowing of population growth. If Mexican fertility had fallen beginning in 1955, the population under 15 would have been most effected. The income per equivalent adult consumer might have been higher, the gains in school attendance and literacy might have covered a larger percentage of the population, and declining rather than increasing absolute numbers of persons might have been unaffected by the gains. Creation of employment opportunities for fewer persons entering the labor force would have been easier than for the large number of new entrants who will need work over the next 20 years.^ieng

Application of demographic methods in population planning.

PIP: Although demographic methods help population program planning by providing quantitative formulas, the validity of the projections depend on the assumptions made and the quality of input data. Particularly in the case of reproductive performance, which is independently influenced by a variety of factors, projections present problems. In order to develop effective population programs planners must recognize all dimensions of population change.^ieng

Economic development and population growth.

PIP: High rates of population growth cause the population to be younger reducing the relative number of persons of productive age. The younger cohorts are not easily absorbed into the labor market or adequately educated because of lack of funds. The rate of population growth also affects the distribution of the population as illustrated in the high degree of migration to cities from rural areas. The size of the population affects the amount of population pressure experienced by the economy and the degree of division of labor. Aside from growth factors, population size itself affects the economy. Although a large population can be healthy for the economy, this seldom seems to be the case in developing countries because of the restricted availability of resources.^ieng

Demographic growth and health needs in Latin America.

The net effect of the rapid population growth in Latin American countries is an increase in the needs for health services. Nevertheless, the demographic factor is not the only nor the most important consideration in determining how to satisfy these demands in the region. The main contradiction lies between the magnitude of needs for services generated by the adverse living conditions prevalling among the majority of the population, together with a restricted supply of health services, the availability of which varies according to social class. The problem of the increasing demand for medical care, generated by the rapid population growth, should be recognized as originating in the socioeconomic structural conditions prevailing in Latin American countries today which determine, simultaneously, low health levels, deficiencies in the provision of health services, and rapid population growth.

PIP: Unfavorable living conditions prevailing in Latin America are exacerbated by rapid population growth. Where the socioeconomic level is very low the need for health care services is very severe. 71% of the high per capita income population in Chile (1.00 and more) satisfied their demand for annual medical visits, compared to 39% of the low income (.0-.19) in 1968. A health policy which delivers medical services to the population sector which most needs them and does not discriminate by social class would reduce the present high rates of population growth. Population projections by the Latin American Demographic Center anticipate increases by an average of 50% between 1975-1990. Estimated growth will exceeded 60% in Honduras, Nicaragua, Mexico, and the Dominican Republic. Since life expectancy is lowest in Nicaragua and Honduras, demographic increase will occur where health needs are the greatest. By contrast, Argentina and Uruguay, where life expectancy is the highest, anticipate 20% growth.

Child saving and child spacing in Africa: the evolution of a concept.

PIP: In 1963 neither the Nigerian Society of Health nor anyone in the power structure of Nigeria would publicly endorse family planning. By early 1968 a family planning day was declared where it was proclaimed that the quality of the people was important not the quantity. However Nigeria still does not have a family planning program that reaches a large percentage of the women at risk. The first phase is a quiet beginning, the second is the achievement of acceptance, the third is to train teachers, and the fourth phase is the establishment of maternal-child care services. This last phase may incorporate the family planning services. Is hoped that this will lead to a more favorable attitude toward family planning.^ieng