Development of the Male and Female Reproductive Systems

The graphs below show the numbers of male and female workers in 1975 and 1995 in several employment sectors of the republic of Freedonia. Write a report for a university teacher describing the information shown.You should write at least 150 words. You should spend about 20 minutes on this task. model answer: The two decades between 1975 and 1995 brought significant changes in the representation of women in Freedonia's work force, according to the graphs. In 1975, for example, some 300 000 men and 250 000 women worked in the communications sector. Twenty years later, though the number of men remained unchanged, the number of women rose to 550 000. A similar situation was seen in the wholesale and retail trade sector, where the number of women rose from about 550 000 in 1975 to almost 800 000 two decades later. The number of men in this sector remained stable over the period, at around 700 000. Women also made gains in both the finance/banking industries and in the defence-related public sector. Whereas some 125 000 women worked in finance and banking institutions in 1975, the number increased to 450 000 by 1995. The number of men grew only marginally from 425 000 to 480 000 over the same period. In defence, the number of men declined from 225 000 to 200 000, while the number of women rose from 25 000 to over 100 000. Two sectors that retained stable employment numbers for both men and women were manufacturing, which had about 300 000 women and 650 000 men in both surveyed years, and the public sector (non-defence), which employed 650 000 women and 850 000 men. Thus, women appear to have made gains in the Freedonian work force but not at the expense of men. (243 words) Development of the Male and Female Reproductive Systems Development of the Male and Female Reproductive Systems Bởi: OpenStaxCollege The development of the reproductive systems begins soon after fertilization of the egg, with primordial gonads beginning to develop approximately one month after conception Reproductive development continues in utero, but there is little change in the reproductive system between infancy and puberty Development of the Sexual Organs in the Embryo and Fetus Females are considered the “fundamental” sex—that is, without much chemical prompting, all fertilized eggs would develop into females To become a male, an individual must be exposed to the cascade of factors initiated by a single gene on the male Y chromosome This is called the SRY (Sex-determining Region of the Y chromosome) Because females not have a Y chromosome, they not have the SRY gene Without a functional SRY gene, an individual will be female In both male and female embryos, the same group of cells has the potential to develop into either the male or female gonads; this tissue is considered bipotential The SRY gene actively recruits other genes that begin to develop the testes, and suppresses genes that are important in female development As part of this SRY-prompted cascade, germ cells in the bipotential gonads differentiate into spermatogonia Without SRY, different genes are expressed, oogonia form, and primordial follicles develop in the primitive ovary Soon after the formation of the testis, the Leydig cells begin to secrete testosterone Testosterone can influence tissues that are bipotential to become male reproductive structures For example, with exposure to testosterone, cells that could become either the glans penis or the glans clitoris form the glans penis Without testosterone, these same cells differentiate into the clitoris 1/7 Development of the Male and Female Reproductive Systems Not all tissues in the reproductive tract are bipotential The internal reproductive structures (for example the uterus, uterine tubes, and part of the vagina in females; and the epididymis, ductus deferens, and seminal vesicles in males) form from one of two rudimentary duct systems in the embryo For proper reproductive function in the adult, one set of these ducts must develop properly, and the other must degrade In males, secretions from sustentacular cells trigger a degradation of the female duct, called the Müllerian duct At the same time, testosterone secretion stimulates growth of the male tract, the Wolffian duct Without such sustentacular cell secretion, the Müllerian duct will develop; without testosterone, the Wolffian duct will degrade Thus, the developing offspring will be female For more information and a figure of differentiation of the gonads, seek additional content on fetal development Interactive Link Feature A baby’s gender is determined at conception, and the different genitalia of male and female fetuses develop from the same tissues in the embryo View this animation to see a comparison of the development of structures of the female and male reproductive systems in a growing fetus Where are the testes located for most of gestational time? Further Sexual Development Occurs at Puberty Puberty is the stage of development at which individuals become sexually mature Though the outcomes of puberty for boys and girls are very different, the hormonal control of the process is very similar In addition, though the timing of these events varies between individuals, the sequence of changes that occur is predictable for male and female adolescents As shown in [link], a concerted release of hormones from the hypothalamus (GnRH), the anterior pituitary (LH and FSH), and the gonads (either testosterone or estrogen) is responsible for the maturation of the reproductive systems and the development of secondary sex characteristics, which are physical changes that serve auxiliary roles in reproduction The first changes begin around the age of eight or nine when the production of LH becomes detectable The release of LH occurs primarily at night during sleep and precedes the physical changes of puberty by several years In pre-pubertal children, the sensitivity of the negative feedback system in the hypothalamus and pituitary is very high This means that very low concentrations of androgens or estrogens will negatively 2/7 Development of the Male and Female Reproductive Systems feed back onto the hypothalamus and pituitary, keeping the production of GnRH, LH, and FSH low As an individual approaches puberty, two changes in sensitivity occur The first is a decrease of sensitivity in the hypothalamus and pituitary to negative feedback, meaning that it takes increasingly larger concentrations of sex steroid hormones to stop the production of LH and FSH The second change in sensitivity is an increase in sensitivity of the gonads to the FSH and LH signals, meaning the gonads of adults are more responsive to gonadotropins than are the ... Journal of Water and Environment Technology, Vol.2, No.2, 2004 - 37 - DEVELOPMENT OF THE OZONIZER AND OZONATION TECHNOLOGY FOR WATERWORKS IN JAPAN Hiroshi HOSHIKAWA*, Takayuki MORIOKA*, Shigeru HATSUMATA* * Fuji Electric Systems Co., Ltd., 11-2 Osaki 1-chome, Shinagawa-ku, Tokyo 141-0032、Japan ABSTRACT Advanced water treatment facilities are used widely, mainly to remove taste and odor and to reduce trihalomethane generation. Each such facility consists of an ozonation and biological activated carbon (BAC) process and has made the achievement in wateworks (Sato, 2002). To make these facilities more efficient, a large number of researchers were taken to make the ozonizer more efficient and to enhance treatment technology. The ozonizer was reduced in the discharge gap using oxygen, and thus increasing ozone concentrations to 300 g/Nm 3 . However, to avoid incomplete combustion and ensure safety, ozone concentrations must be within 150 g/Nm 3 (Ishioka, 2002; Mizutani et al.,1999). The present report also demonstrates that ozonation technology is effective in removing taste and odor and in reducing trihalomethane ( Morioka et al., 1993; Morioka, 2001); and that bromate information can be suppressed by keeping concentrations of dissolved ozone to no more than 0.1 mg/L ( Kato et al 2002). To spread and establish ozonation more widely, basic research with demonstrative plants must be conducted with regard to ozonation techniques that are capable of handling raw water from waterworks. KEYWORDS Ozonation; ozonizer; Silent discharge method; Biological activated carbon(BAC); Trihalomethane; Bromate INTRODUCTION Waterworks sources in the largest cities are highly contaminated, and advanced water treatment facilities have been introduced, with favorable results, to remove taste and odor and to reduce trihalomethane that cannot be treated with conventional techniques of water purification. Advanced water treatment facilities consist mainly of ozonation and biological activated carbon (BAC) treatment. Ozone has powerful oxidation capability, and is thus able to treat both of them. However, for highly efficient treatment, it is important to increase ozone generation efficiency and to cause necessary and sufficient oxidation reactions in ozone contact basins. Following the introduction of ozonation, new challenges have appeared such as information of bromate by ozonation and inactivation of cryptosporidium. These must also be solved. The present report addresses these issues, together with techniques to solve those Journal of Water and Environment Technology, Vol.2, No.2, 2004 - 38 - problems, and classifies them into ozonizer (which is the key hardware in advanced water treatment facilities) and ozonation techniques. The report then describes the recent status of each of the issues. RESEARCH AND DEVELOPMENT IN INCREASING OZONE CONCENTRATION Ozone generation Method and scale of use Table 1 summarizes the ozone generation method and their scales of use. Table 1. Processes for ozone generation and their scales of use Item UV irradiation Electrolysis Silent discharge Utility ＜0.1kg/h 〇 〇 〇 Laboratory Pool 0.1～1kg/h 〇 〇 Wastewater Night soil 1kg/h＜ 〇 Drinking water Sewage water Ozone can be produced by ultraviolet irradiation, electrolysis, and silent discharge methods. The appropriate method is selected Development of the Quantitative PCR Method for Candidatus ‘Accumulibacter phosphatis’ and Its Application to Activated Sludge Toshikazu Fukushima*, Naoki Uda*, Motoharu Onuki**, Hiroyasu Satoh* and Takashi Mino* * Institute of Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8563, Japan (E-mail: fukushima@mw.k.u-tokyo.ac.jp) ** Integrated Research System for Sustainability Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan ABSTRACT To quantify Candidatus ‘Accumulibacter phosphatis’ in activated sludge, quantitative PCR method was developed utilizing SYBR GREEN I and a specific primer set targeted on the 16S rRNA gene of Candidatus ‘Accumulibacter phosphatis’. Following optimization of PCR condition, specificity was evaluated based on the melting curve and the sequencing analysis of the PCR products with DNA extracted from activated sludge. Both the melting curve and the sequencing analysis of the PCR product showed that only the target DNA from Candidatus ‘Accumulibacter phosphatis’ was amplified. Standard curves with a series of tenfold dilution of the DNA from 16S rRNA gene fragment of Candidatus ‘Accumulibacter phosphatis’ gave R 2 values greater than 0.999. The minimum detection limit was 1.0×10 3 copies per reaction. The amount of Candidatus ‘Accumulibacter phosphatis’ in laboratory-scale and full-scale activated sludge samples were quantified both by the quantitative PCR method and by the FISH method. The quantification results by these two methods agreed satisfactorily, with an R 2 value of 0.6871 showing a statistically significant correlation (p<0.001). Thus, we developed a rapid quantification method by using quantitative PCR for the quantification of Candidatus ‘Accumulibacter phosphatis’ in activated sludge. Keywords: Quantitative PCR; SYBR GREEN I; Candidatus ‘Accumulibacter phosphatis’; Activated Sludge INTRODUCTION Candidatus ‘Accumulibacter phosphatis’ is currently thought to be the most relevant polyphosphate accumulating organisms (PAOs) in the enhanced biological phosphorus removal (EBPR) process (Seviour et al., 2003; Mino et al., 1998). Hesselmann et al. (1999) and Crocetti et al. (2000) revealed that the bacteria closely related to Rhodocyclus (a member of the β-Proteobacteria) were progressively enriched and responsible for phosphorus removal in laboratory-scale EBPR reactors fed with acetate by using newly designed oligonucleotide probes. Hesselmann et al. (1999) reported that the bacteria was a coccobacillus and tentatively proposed its name as Candidatus ‘Accumulibacter phosphatis’. In further study, Candidatus ‘Accumulibacter phosphatis’ has frequently been found to dominate many laboratory-scale EBPR cultures (Onuki et al., 2002; Liu et al., 2001; Oehmen et al., 2005) and has also been observed in abundance in full-scale wastewater treatment plants by using fluorescence in situ hybridization (FISH) (Wong et al., 2005; Beer et al., 2006). It is therefore important to accurately and easily assess the contribution of Candidatus ‘Accumulibacter 27 CONTROL OF THE CHASSIS AND ‘BY WIRE’ SYSTEMS 27.1 MOTOR VEHICLE CONTROL As already stated, a road vehicle on pneumatic tires cannot maintain a given trajectory under the effect of external perturbations unless managed by some control device, which is usually a human driver. Its stability solely involves such state variables as the sideslip angle β and the yaw velocity r. In the case of two-wheeled vehicles the capsize motion is intrinsically unsta- ble forcing the driver not only to control the trajectory but stabilize the vehicle. A possible scheme of the vehicle-driver system is shown in Fig. 27.1. The driver is assumed to be able to detect the yaw angle ψ, the angular and linear accelerations ˙ β,˙r, dV/dt, V 2 /R and to be able to assess his position on the road (X and Y ). Moreover, the driver receives other information from the vehicle, such as forces, moments, noise, vibrations, etc. that allow him to assess, largely unconsciously, the conditions of the vehicle and the road-wheel interactions. 27.1.1 Conventional vehicles In all classical vehicles of the second half of the twentieth century up to the 1990s, the driver had to perform all control and monitoring tasks. The only assistance came from devices like power steering or power brakes that amplified the force the driver exerted on the controls. In this situation, the human controller is fully inserted in the control loop or, as usually said, the systems include a human in the loop. G. Genta, L. Morello, The Automotive Chassis, Volume 2: System Design, 429 Mechanical Engineering Series, c  Springer Science+Business Media B.V. 2009 430 27. CONTROL OF THE CHASSIS AND ‘BY WIRE’ SYSTEMS FIGURE 27.1. Simplified scheme of the vehicle-driver system. Actually the driver must control high level functions (choice of the trajec- tory, decisions about speed and driving style, about manoeuvres like overtaking, etc.) and intermediate level functions (reacting to perturbations coming from the air and the road, following the chosen trajectory, etc.). Only stability at the lowest level, involving the sideslip angle and the yaw velocity, is provided by the dynamic behavior of the vehicle. As already stated, in motorbikes the driver must also act as a stabilizer against capsizing. In particular: • Direction control is implemented by applying a torque to the steering wheel that is then transmitted through a mechanical system (steering box, steering arms, various linkages) to the steering wheels, which are al- ways the front wheels. The torque exerted by the driver may be increased by an hydro-pneumatic or electromechanical system (power steering) that nonetheless never replaces the driver by exerting the whole moment. The required sensitivity is provided by the torque the steering system exerts on the driver through the aligning torque and the contact forces at the wheel- road interface. These, in turn, depend upon the geometry of the steering system (caster angle, toe in, offsets, etc.). • The control of the power supplied by the engine is managed through the accelerator pedal, operating directly through a mechanical leverage. Sensi- tivity is supplied by the elastic reaction of a spring that reacts to the motion of the pedal. The driver must control the power accurately enough so that the maximum force the wheel can exert on the ground is not exceeded. • Engine control is accompanied by control of the gearbox and the clutch, which operate through the clutch pedal and the gear lever. These controls are often automatic. 27.1 Motor vehicle control 431 • Braking control is performed by applying a force on the brake pedal that is then transmitted through a system (usually hydraulic, but pneumatic in industrial vehicles) to the brakes located in all wheels. Here the force ex- erted by the driver can also be augmented by a hydro-pneumatic device (power braking). In all cases, sensitivity is granted by the fact that the force exerted by the driver is proportional (or at least depends in an DEVELOPMENT OF THE FINITE AND INFINITE INTERVAL LEARNING CONTROL THEORY JING XU NATIONAL UNIVERSITY OF SINGPAORE 2003 DEVELOPMENT OF THE FINITE AND INFINITE INTERVAL LEARNING CONTROL THEORY BY JING XU (B. ENG., M. ENG.) A DISSERTATION SUBMITTED IN PARTICIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCOTOR OF PHILOSOPHY IN ENGINEERING NATIONAL UNIVERSITY OF SINGAPORE 2003 Acknowledgments I would like to express my deepest gratitude to my supervisor, Prof. Xu JianXin, for his valuable guidance, encouragement and patience during my entire PhD study. His wealthy knowledge and accurate foresight have impressed and benefited me very much, especially in the area of nonlinear control and learning control. Moreover, his rigorous scientific approach and endless enthusiasm to the career have influenced me significantly. Without his continuous guidance and help, I could not have accomplished this thesis and all the relevant works. Thanks are also presented to the researchers, working in the center of intelligent control of the Electrical & Computer Engineering Department, National University of Singapore, for their encouragement and valuable advice. I would like to take this opportunity to thank Dr. Chen Jianping, Mr. Zhang Hengwei, Dr. Pan Yajun, Ms. Yan Rui, Ms. Zheng Qing and all the other labmates in the Control & Simulation Lab for their kindly assistance in both my research work and the other personal aspects. My very special thanks go to Dr. Tan Ying from whom I have learned a lot via frequent discussions. Finally, I am indebted to my parents, my husband Mr. Ou Ke and my younger sister Miss Wei Zeli, for their constant support and encouragement throughout all my studies. It is impossible to thank them adequately. I would like to dedicate this thesis to all my family members. Xu Jing June 2003 i Contents Acknowledgments i Contents ii Summary vii List of Tables ix List of Figures ix Introduction 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.1 Finite Interval Learning Control (FIL) . . . . . . . . . . . . . 1.1.2 Infinite Interval Learning Control (IIL) . . . . . . . . . . . . . 10 1.1.3 Learning for Nonsmooth Nonlinearities . . . . . . . . . . . . . 12 1.2 Objective of This Thesis . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.3 Thesis Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 ii Contents iii FIL for Systems with Input Deadzone 23 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 2.2 Preliminaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.3 FIL for A Pure Deadzone Component . . . . . . . . . . . . . . . . . . 25 2.4 FIL for Dynamic Systems with Input Deadzone . . . . . . . . . . . . 28 2.5 Illustrative Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 2.6 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 2.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 FIL for Systems with Input Backlash 46 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 3.2 FIL for A Pure Backlash Component . . . . . . . . . . . . . . . . . . 47 3.3 FIL for Dynamic Systems with Input Backlash . . . . . . . . . . . . . 51 3.4 Illustrative Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 3.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 FIL for Systems with Norm-bounded Uncertainties 60 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 4.2 FIL for SISO Systems with Norm-bounded Uncertainties . . . . . . . 61 4.2.1 FIL for Systems with GLC Uncertainties . . . . . . . . . . . . 62 4.2.2 FIL for Systems with NGLC Uncertainties . . . . . . . . . . . 65 Contents iv 4.3 FIL for Norm-bounded Uncertainties under Alignment Condition . . 69 4.3.1 FIL for GLC Systems under Alignment Condition . ... and the different genitalia of male and female fetuses develop from the same tissues in the embryo View this animation to see a comparison of the development of structures of the female and male. .. of the Male and Female Reproductive Systems Development of the Secondary Sexual Characteristics Male Female Growth of facial, axillary, and pubic hair, and Broadening of the pelvis and growth... the hypothalamus and pituitary gland, and an increase in sensitivity of the gonads to FSH and LH stimulation These changes lead to increases in either 5/7 Development of the Male and Female Reproductive