SI}} {{CMG}} A sex-determination system is a [[biology,biological]] system that determines the development of [[sex,sexual characteristics]] in an [[organism]]. Most sexual organisms have two [[sex]]es. In many cases, sex determination is genetic: [[male]]s and [[female]]s have different [[allele]]s or even different [[gene]]s that specify their sexual [[Comparative anatomy,morphology]]. In [[animal]]s, this is often accompanied by [[chromosome,chromosomal]] differences. In other cases, sex is determined by [[ecosystem,environmental]] variables (such as [[temperature]]) or social variables (the size of an [[organism]] relative to other members of its [[population]]). The details of some sex-determination systems are not yet fully understood. ==Chromosomal determination== === XX/XY sex chromosomes === {{Main,XY sex-determination system}} The XX/XY sex-determination system is one of the most familiar sex-determination systems and is found in [[human]] beings and most other [[mammal]]s. ...
SEX ratio is a central demographic parameter directly related to the reproductive potential of individuals and populations (Penman and Piferrer 2008). The phenotypic sex depends on the processes of both sex determination and sex differentiation. Exogenous factors, such as temperature, hormones, or social behavior, can modify the gonad development pathway in fish (Baroiller and DCotta 2001; Piferrer and Guiguen 2008). Both genetic (GSD) and environmental sex determination has been reported in this group (Devlin and Nagahama 2002; Penman and Piferrer 2008), although primary sex determination is genetic in most species (Valenzuela et al. 2003). Among GSD, single, multiple, or polygenic sex-determining (SD) gene systems have been documented (Kallman 1984; Matsuda et al. 2002; Lee et al. 2004; Vandeputte et al. 2007).. Sex determination in fish can evolve very rapidly (Woram et al. 2003; Peichel et al. 2004; Ross et al. 2009). Different sex determination mechanisms have been reported between ...
This is the first report, to the best of our knowledge, of a molecular difference in a sex-determining gene between reptiles with GSD or TSD. Several lines of evidence support the idea that this amino acid shift accompanies turnover of sex-determining mechanisms. Dmrt1 is known to direct sexual development in chicken [12], a species found within Reptilia, a clade known for frequent and reversible changes in sex-determining mechanism [1]. Dmrt1 is expressed more in gonadal tissues of males than of females, even in a turtle that has TSD [26]. In other species, including mice and rats, Dmrt1 contributes to male sexual development but does not act first among sex-differentiating genes [27]. Capture or influence by one gene on sexual development could occur at any point in the gene cascade [28]. Therefore, we are not surprised to find exceptions to the two AA pattern across sampled reptiles. Sex-determining mechanisms have changed frequently, suggesting more than one cause. GSD, in extant therian ...
The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila), some snakes, and some plants (Ginkgo). In this system, the sex of an individual is determined by a pair of sex chromosomes. Females typically have two of the same kind of sex chromosome (XX), and are called the homogametic sex. Males typically have two different kinds of sex chromosomes (XY), and are called the heterogametic sex. In humans, the presence of the Y chromosome is responsible for triggering male development; in the absence of the Y chromosome, the fetus will undergo female development. More specifically, it is the SRY gene located on the Y chromosome that is of importance to male differentiation. Variations to the sex gene karyotype could include rare disorders such as XX males (often due to translocation of the SRY gene to the X chromosome) or XY gonadal dysgenesis in people who are externally female (due to mutations in the SRY gene). In addition, other ...
CONSIDERING the fundamental importance of sex for species propagation, it is surprising that primary sex-determining mechanisms are not strongly conserved among animal taxa (Bull 1983; Charlesworth 1996; Ming et al. 2011; Bachtrog et al. 2014). Closely related species or even populations of the same species can have different sex-determining mechanisms (Takehana et al. 2007; Ross et al. 2009; Kobayashi et al. 2013; Heule et al. 2014; Larney et al. 2014). Zebrafish (Danio rerio) is a popular model for studies of vertebrate development, behavior, physiology, evolution, disease, and human health (Mills et al. 2007; Seth et al. 2013; Braasch et al. 2014; Ota and Kawahara 2014; Wilkinson et al. 2014), but researchers struggle with highly variable and distorted sex ratios, and investigations into the genetic nature of zebrafish sex determination are conflicting. To help understand these issues, we conducted a population genomic study of sex determination in multiple zebrafish strains.. Zebrafish ...
Author Summary The sex determination system extremely diverse among organisms including insects in which even each order occupy a different manner of sex determination. The silkworm, Bombyx mori, is a lepidopteran model insect with economic importance. The mechanism of the silkworm sex determination has been in mystery for a long time until a Fem piRNA was identified as the primary female sex determinator recently. However, genetic and phenotypic proofs are urgently needed to fully exploit the mechanism, especially of the male sex determination. In the current study, we provided comprehensively genetic evidences by generating CRISPR/Cas9-mediated knockout mutations for those genes BmSxl, Bmtra2, BmImp, BmImpM, BmPSI and BmMasc, which were considered to be involved in insect sex determination. The results showed that mutations of BmSxl, BmImp and BmImpM had no physiological and morphological effects on the sexual development while Bmtra2 depletion caused Bmdsx splicing disappeared and induced embryonic
Brief oversimplification: Most bees, ants, and true wasps have a single sex-determining locus (no sex chromosomes) with many alleles. Haploids are male, and diploids are almost always heterozygous at the sex locus and become female. Homozygous diploids develop as males, and these diploid males are usually inviable or infertile. This is called single-locus complementary sex determination, or sl-CSD (or just CSD). Just a few years ago, the sex locus of the honeybee was definitively identified by Martin Beye and co-workers ...
Sex determinations are diverse in vertebrates. Although many sex-determining genes and pathways are conserved, the mechanistic roles of these genes and pathways in the genetic sex determination are not well understood. DAX1 (encoded by the NR0B1 gene) is a vertebrate specific orphan nuclear receptor that regulates gonadal development and sexual determination. In human, duplication of the NR0B1 gene leads to male-to-female sex reversal. In mice, Nr0b1 shows both pro-testis and anti-testis functions. We generated inheritable nr0b1 mutation in the zebrafish and found the nr0b1 mutation caused homozygous mutants to develop as fertile males due to female-to-male sex reversal. The nr0b1 mutation did not increase Caspase-3 labeling nor tp53 expression in the developing gonads. Introduction of a tp53 mutation into the nr0b1 mutant did not rescue the sex-reversal phenotype. Further examination revealed reduction in cell proliferation and abnormal somatic cell differentiation in the nr0b1 mutant gonads at ...
In most mammals, the Y chromosomal Sry gene initiates testis formation within the bipotential gonad, resulting in male development. SRY is a transcription factor and together with SF1 it directly up-r
As a consequence of genetic sex determination, the indifferent gonadal blastema normally becomes either a testis or an ovary. This applies to mammals and to the majority of non-mammalian vertebrates. With the exception of placental mammals, however, partial or complete sex inversion can be induced in one sex by sexual steroid hormones of the opposite sex during a sensitive period of gonadogenesis. There is evidence that also during normal gonadogenesis in these species, in the XY/XX mechanism of sex determination testicular differentiation is induced by androgens, and in the ZZ/ZW mechanism, ovarian differentiation by oestrogens. In either case, the hormones may act via serological H-Y antigen as a morphogenetic factor. In contrast, in placental mammals including man, primary gonadal differentiation is independent of sexual steroid hormones, and factors directing differential gonadal development have not yet been conclusively identified. However, various mutations at the chromosome or gene ...
In vertebrates with separate sexes, sex determination can be genotypic (GSD) or temperature-dependent (TSD). TSD is very common in reptiles, where the ambient temperature during sensitive periods of early development irreversibly determines whether an individual will be male or female. The number of males and females in a population is the sex ratio, a key demographic parameter crucial for population viability.
Matthey-Doret, C., van der Kooi, C. J., Jeffries, D. L., Bast, J., Dennis, A. B., Vorburger, C., & Schwander, T. (2019). Mapping of multiple complementary sex determination loci in a parasitoid wasp. Genome Biology and Evolution, 11(10), 2954-2962. https://doi.org/10.1093/gbe/evz219 ...
Sex determination (SD) systems are remarkably variable across life, yet the evolutionary significance of this variation is poorly understood. And not just the forces that shape this variation, but also those that shape the taxonomic distribution of the different sex determination systems remain elusive. For example, some systems like XX/XY sex chromosomes seem to have evolved over and over, while others like haplodiploidy (where males develop from unfertilized eggs, while females develop from fertilized eggs) are much less frequent and restricted to a smaller number of taxonomic groups. The aim of the proposed project is two-fold. First of all we will describe and review the taxonomic distribution of SD systems among the insects and their closest relatives. This review will be based on data from over ten thousand species that were collected from the cytogenetic literature and will be the most comprehensive till date. Secondly we will use a formal comparative approach to understand the ...
Theory predicts that the mechanism of genetic sex determination can substantially influence the evolution of sexually selected traits. For example, female heterogamety (ZZ/ZW) can favour the evolution of extreme male traits under Fishers runaway model of sexual selection. We empirically test whether the genetic system of sex determination has played a role in the evolution of exaggerated male ornaments in actinopterygiian fishes, a clade in which both female-heterogametic and male-heterogametic systems of sex determination have evolved multiple times. Using comparative methods both uncorrected and corrected for phylogenetic non-independence, we detected no significant correlation between sex-chromosome systems and sexually selected traits in males. Results suggest that sex-determination mechanism is at best a relatively minor factor affecting the outcomes of sexual selection in ray-finned fishes ...
These neurovascular foramina are very numerous and densely packed, which is taken to be indicative of a highly sensitive snout. This is also seen in modern Crocodylians, where the facial skin plays an important role in a number of behaviours, most notably detecting movements in water that could indicate potential prey, and monitoring the temperature of nesting sites (very important for Crocodylians, which have a temperature dependent method of sex determination). Tyrannosaurids are thought to have been terrestrial hunters, making it highly unlikely that they would have used sensitive facial skin to detect movements in the water, and though Carr et al, consider it quite likely that they had a temperature dependent sex determination system and a consequent need to asses the temperature of nesting sites, they feel that this in itself would be unlikely to be the sole reason for the high levels of neurovascular development in the face of Daspletosaurus horneri. Instead they suggest that this area of ...
Author Summary How cells diverge from a common progenitor and adopt specific fates is still poorly understood. We analyzed gene expression profiles in the distinct cell lineages of the gonad over the period when sex determination occurs. The undifferentiated progenitor cells expressed genes characteristic of both sexual fates, explaining the plasticity of the gonadal cells to differentiate as male or female cell types. The establishment of sex-specific fate in both the germ cells and somatic cells involved activation of some genes; but, importantly, we show that an active repression of genes associated with the alternative pathway is also a characteristic of cell fate commitment. Although germ cell progenitors expressed genes associated with both possible fates, genes characteristic of the male fate were over-represented in the progenitors, giving them a male bias. However, in somatic cell progenitors, which control sex determination, genes associated with the female fate were over-represented. These
In many vertebrates, sex of offspring is determined by external environmental cues rather than by sex chromosomes. In reptiles, for instance, temperature-dependent sex determination (TSD) is common. Despite decades of work, the mechanism by which temperature is converted into a sex-determining signal remains mysterious. This is partly because it is difficult to distinguish the primary molecular events of TSD from the confounding downstream signatures of sexual differentiation. We use the Australian central bearded dragon, in which chromosomal sex determination is overridden at high temperatures to produce sex-reversed female offspring, as a unique model to identify TSD-specific features of the transcriptome. We show that an intron is retained in mature transcripts from each of two Jumonji family genes, JARID2 and JMJD3 , in female dragons that have been sex-reversed by temperature but not in normal chromosomal females or males. JARID2 is a component of the master chromatin modifier Polycomb ...
The karyotypes of three species of Pyrgomorphidae grasshoppers were studied: Zonocerus elegans (Thunberg, 1815), Pyrgomorpha guentheri (Burr, 1899) and Atractomorpha lata (Mochulsky, 1866). Data on karyotypes of P. guentheri and Z. elegans are reported here for the first time. All species have karyotypes consisting of 19 acrocentric chromosomes in males and 20 acrocentric chromosomes in females (2n♂=19, NF=19; 2n♀=20, NF=20) and X0/XX sex determination system. A comparative analysis of the localization of C-heterochromatin, clusters of ribosomal DNA, and telomere repeats revealed inter-species diversity in these cytogenetic markers. These differences indicate that the karyotype divergence in the species studied is not associated with structural chromosome rearrangements, but with the evolution of repeated DNA sequences.
The karyotypes of three species of Pyrgomorphidae grasshoppers were studied: Zonocerus elegans (Thunberg, 1815), Pyrgomorpha guentheri (Burr, 1899) and Atractomorpha lata (Mochulsky, 1866). Data on karyotypes of P. guentheri and Z. elegans are reported here for the first time. All species have karyotypes consisting of 19 acrocentric chromosomes in males and 20 acrocentric chromosomes in females (2n♂=19, NF=19; 2n♀=20, NF=20) and X0/XX sex determination system. A comparative analysis of the localization of C-heterochromatin, clusters of ribosomal DNA, and telomere repeats revealed inter-species diversity in these cytogenetic markers. These differences indicate that the karyotype divergence in the species studied is not associated with structural chromosome rearrangements, but with the evolution of repeated DNA sequences.
Sex determination relies on a hierarchically structured network of genes, and is one of the most plastic processes in evolution. The evolution of sex-determining genes within a network, by neo- or sub-functionalization, also requires the regulatory landscape to be rewired to accommodate these novel gene functions. We previously showed that in medaka fish, the regulatory landscape of the master male-determining gene dmrt1bY underwent a profound rearrangement, concomitantly with acquiring a dominant position within the sex-determining network. This rewiring was brought about by the exaptation of a transposable element (TE) called Izanagi, which is co-opted to act as a silencer to turn off the dmrt1bY gene after it performed its function in sex determination. We now show that a second TE, Rex1, has been incorporated into Izanagi. The insertion of Rex1 brought in a preformed regulatory element for the transcription factor Sox5, which here functions in establishing the temporal and cell-type-specific
We previously identified a primary sex-determining locus, Tas, on mouse Chr 17 that causes ovarian tissue development in C57BL/6J Thp/+ and TOrl/+ individuals if the AKR/JY chromosome is present. We hypothesized that Tas is located within the region of Chr 17 deleted by Thp and TOrl and that C57BL/6J carries a diagnostic Tas allele, based on the observation that ovarian tissue develops in XY mice when Thp is on a C57BL/6J inbred strain background, whereas normal testicular development occurs when Thp is on a C3H/HeSnJ inbred strain background. To test this hypothesis, we mated (C57BL/6J x C3H/HeSnJ)F1 females to C57BL/6J Thp/+ hermaphrodites. As expected, half of the XY Thp/+ offspring developed ovarian and testicular tissue while half developed exclusively testicular tissue. Unexpectedly, the inheritance of selected Chr 17 molecular loci was independent of gonadal development, as half of the male and hermaphroditic offspring inherited C3H/HeSnJ-derived Chr 17 loci and half inherited C57BL
Sex determination (male/female) at the biological level is determined by the presence or absence of the Y chromosome. Initially, we did not know what this factor was and it was designated the "testis determining factor" (TDF). We now know (since 1990) that TDF is the protein product encoded by the SRY gene on the Y chromosome. Without this gene/protein the potential sex is female (see Male below). For some time, female was considered the "default" sex in the absence of SRY, we now know this is not the case, with several genes specifically required for ovary formation. In females, sex determination involves at least one X chromosome gene, DAX1 encoding a nuclear hormone receptor. Another critical genetic issue is related to the presence of two X chromosomes, "gene dosage", and in the case of mammals this is regulated by inactivating one of those X chromosomes in each and every cell (see Female below). ...
Sex determination switch protein which controls sexual development by sex-specific splicing. Regulates dosage compensation in females by suppressing hyperactivation of X-linked genes. Expression of the embryo-specific isoform is under the control of primary sex-determining signal, which depends on the ratio of X chromosomes relative to autosomes (X:A ratio). Expression occurs in 2X:2A cells, but not in X:2A cells. The X:A ratio seems to be signaled by the relative concentration of the X-linked transcription factors SIS-A and SIS-B. As a result, the embryo-specific product is expressed early only in female embryos and specifies female-adult specific splicing; in the male where it is not expressed, the default splicing gives rise to a truncated non-functional protein. The female-specific isoform specifies the splicing of its own transcript, thereby initiating a positive autoregulatory feedback loop leading to female development pathway. The female-specific isoform controls the sex-specific splicing of
Une eau douce est une eau qui contient peu de sels dissous. , Soft water is (a) water that is free of dissolved salts./toolbox/gender_number/determiners/audio/une_eau_douce_est_une_eau_qui_continent_peu_de_sels_dissous.mp3 ...
To determine the latitudinal pattern of sex determination, embryos from M. menidia were collected from 31 locations along the species range from Amelia Island, FL (30° 31.13 N, 081° 27.78 W) to the Magdalen Islands, Quebec, Canada (47° 23.60 N, 061° 50.76 W) (Table 1, See Hice et al. (2012) for detailed methods). This resulted in collection sites that averaged 60-80 km from each other for complete coverage of M. menidias range (Figure 1). Briefly, spawning adult M. menidia were collected with a 30m seine net, stripped spawned following the methods employed by Lagomarsino and Conover (1993) and embryos were transported to Flax Pond Laboratory in Old Field, NY or the Bluepoint Laboratory in West Sayville, NY. Larvae of mixed parentage were pooled and randomly allocated into 15 °C or 28 °C in triplicate containers prior to sex determination (Conover and Fleisher 1986). Density per container was periodically adjusted and fish were euthanized when they reached a minimum of 21-23 mm TL. ...
At present, aquaculture is the fastest growing sector of animal food production and holds great potential as a sustainable solution for world food security. The ability to control sex is one of the most important factors for the commercialisation and efficient propagation of fish species, due to influences on reproduction, growth and product quality. Accordingly, there is a large body of research that targets sexual development in commercially important species in an attempt to understand and control fish sex and reproductive function. In this review, we provide an introduction to sex determination and differentiation in fish, including the genetic, epigenetic and environmental factors that can influence fish sex ratios. We also summarise the major approaches used to control sex in fish and discuss their application in commercially important species. Specifically, we discuss the use of exogenous steroid hormones, chromosome ploidy, environmental manipulations, sex-linked genetic markers, selection for
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In humans and several other species of animals, the father determines the sex of the child. In the XY sex-determination system, the female-provided ovum contributes an X chromosome and the male-provided sperm contributes either an X chromosome or a Y chromosome, resulting in female (XX) or male (XY) offspring, respectively. [Src: http://en.wikipedia.org/wiki/Maternal_influence_on_sex_determination ...
Understanding the evolution of the X and Y is so important because we need to understand that there are all of these variations in the genetics of sex determination.
Sexual dimorphisms in trait expression are widespread among animals and are especially pronounced in ornaments and weapons of sexual selection, which can attain exaggerated sizes. Expression of exaggerated traits is usually male-specific and nutrition sensitive. Consequently, the developmental mechanisms generating sexually dimorphic growth and nutritiondependent phenotypic plasticity are each likely to regulate the expression of extreme structures. Yet we know little about how either of these mechanisms work, much less how they might interact with each other. We investigated the developmental mechanisms of sex-specific mandible growth in the stag beetle Cyclommatus metallifer, focusing on doublesex gene function and its interaction with juvenile hormone (JH) signaling. doublesex genes encode transcription factors that orchestrate male and female specific trait development, and JH acts as a mediator between nutrition and mandible growth. We found that the Cmdsx gene regulates sex differentiation in the
Exploring how our bodies work and function. The Human Reproduction chart begins with graphics and text describing the male and female reproductive systems. The menstrual cycle, ovulation and fertilization are depicted, along with a section on sex determination.. Item: 8500. ...
Sigma-Aldrich offers abstracts and full-text articles by [Takashi Kiuchi, Hikaru Koga, Munetaka Kawamoto, Keisuke Shoji, Hiroki Sakai, Yuji Arai, Genki Ishihara, Shinpei Kawaoka, Sumio Sugano, Toru Shimada, Yutaka Suzuki, Masataka G Suzuki, Susumu Katsuma].
Juego de Transformers 2 gratis, Organiza la defensa de los autobots para eliminar a la amenaza que provocan los decepticons en este increible juego de transformer. Transformers 2: Music Video byKirby. Subscribe Subscribed Unsubscribe 11,353 11K. Transformers 2 Revenge Of The Fallen Forest Battle with Deleted. June 2017. Watch the Transformers: The Last Knight trailer on the official movie site. In theatres June 2017. TermsPrivacyRatings. #TRANSFORMERS.. Transformers 2 Revenge Of The Fallen Forest Battle with Deleted Scenes 1080p HD LeeButtersnaps. Subscribe Subscribed Unsubscribe 16,236 16K. Loading. The Transformers are a species of sentient, living robotic beings (mostly) originating from the distant machine world of Cybertron. The stories of their lives, their. ASUS Transformer 2 in 1 Laptop Computer With 10.1 Screen Atom Z3735F Processor Model Number T100TAF B12 GR, Features a 10 touch screen display, Includes 1 docking. Transformers. 32,573,665 likes 176,026 talking about this. The official ...
interacting with WNT4 and CTNNB1 (antagonism between SOX9 and CTNNB1 potentially is the molecular mechanism through which the fate of the supporting cell lineage in the gonad is established to drive male or female sex determination ...
Seks na 3 dates, While the evolution of sex dates to the prokaryote or early eukaryote stage, the origin of chromosomal sex determination may have been fairly early in eukaryotes. Watch Anal Seks porn videos for free.
... XX. Majority of organisms are hermaphrodites; only about 1% males ... Hermaphrodite testis and ovaries. During larval stage, testis produce sperm (stored) ... – A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 1430b-MjBhN
Transformer configuration names like and derive from the way the windings are connected inside the transformer. These connections determine the way the transformer will behave, and they also determine the methods of calculation required for properly applying a given transformer. Delta-connected transformers have the windings of three single-phase transformers connected in series with each other to
J:204550 Fujimoto Y, Tanaka SS, Yamaguchi YL, Kobayashi H, Kuroki S, Tachibana M, Shinomura M, Kanai Y, Morohashi K, Kawakami K, Nishinakamura R, Homeoproteins Six1 and Six4 regulate male sex determination and mouse gonadal development. Dev Cell. 2013 Aug 26;26(4):416-30 ...
EPA also issued a regulatory definition of "adjacent" for purposes of making "single source determinations" in the oil and gas sector. Single source determinations are important to oil and gas operators because they can result in the "aggregation" of emissions from multiple sources, potentially triggering onerous "major source" air permit requirements. For a number of years, this issue has been a significant and evolving one. EPA has now brought some clarity to it, which should allow members of the industry to better plan their operations.. Under the CAA, a "stationary source" is defined as "any building, structure, facility, or installation" that emits air pollutants. [7] Longstanding EPA regulations provide that, in order for a group of air-pollutant-emitting units to be considered part of a single "building, structure, facility or installation," three requirements must be satisfied: (1) the units must belong to the same industrial grouping (which is determined with reference to whether they ...
Journal of Chemometrics ; Volume 22. p. 309-322. 2008. Zimonja, Monika; Rudi, Knut; Trosvik, Pål; Næs, Tormod. A comprehensive understanding of factors that influence microbial competition and cooperation, their diversity and processes will be greatly beneficial in many research areas. Current tools for microflora determinations are far from suitable for high-throughput monitoring of development in complex microbial communities. Here, we describe the application of a calibration free method, multivariate curve resolution with alternating least squares (MCR-ALS), for identification and quantification of different microbes in mixture samples. The idea is to utilize MCR-ALS to enable close monitoring of ecology in a variety of microbial communities. The data from two designed experiments consisting of DNA sequence spectra measured on mixtures were analysed with MCR-ALS using no prior information on the data except for appropriate constraints, such as non-negativity and closure. The results were ...
Antibodies are produced by the immune system in response to foreign macromolecules. Each antibody binds specifically to one feature (epitope) on one macromolecule (antigen). This allows the use of antibodies for the detection and quantitation of specific proteins in complex mixtures. Antibodies are generally isolated from animal serum, unless they are produced from tissue culture as monoclonals. The serum must be titrated to determine antibody concentration and specificity. Concentration determinations are often needed for antigen mixtures as well. Immunodiffusion and immunoelectrophoresis are useful techniques for these purposes.. If antibody and antigen are present in solution at approximately equal concentrations, they form an aggregate, which precipitates. This precipitate can be dissolved by the addition of an excess of antibody or of antigen (see figure below).. ...
Controlling a cardiac pacemaker wherein the cardiac pacing rate is controlled according to a measure of the metabolic demand. The average minute ventilation MV-8-0 is measured over the eight last breathing cycles (first one to eighth one), and it is compared with the average minute ventilation MV-8-1 over the previous eight breathing cycles (ninth one to sixteenth one), and it is determined that an effort phase is present when MV-8-0|MV-8-1, and that a recovery phase is present when MV-8-0|MV-8-1. These determinations are used to determine whether sensed changes in the ventilation correspond to transitions between the effort and recovery or ventilation gaps or artifacts so that the cardiac pacing rate is not decreased during an effort.
If you materially participate in an activity you may be able to classify the activity as nonpassive and thus use any losses from that activity to offset other sources of taxable income.. Generally, losses from passive activities can only offset passive income (which, strange though it may seem, does not include income from an investment portfolio). As with all tax things, there are exceptions to these guidelines and these determinations are made annually based on facts and cirumstances: please consult a tax advisor about your individual situation to determine the correct tax treatment.. ...
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Choices regarding diet and lifestyle are the main determiners of how quickly the skin ages, according to a spokesperson from the British Association of Beauty Therapy & Cosmetology (BABTAC).
Articles and numerals as subsumed under determiner. (For dictionary purposes these two should be considered separate, though.) Participles as straddling verb, noun, adjectives, and adverbs, or subsumed under verb. (See singing. When a participle acts as noun or adjective and therethrough acquires special meaning then those special meanings are spun off into separate Noun and Adjective sections, whereas participle proper is listed under Verb; a fraction of a verb, as it were.). ...
A signal processor which acquires a first signal, including a first primary signal portion and a first secondary signal portion, and a second signal, including a second primary signal portion and a se
Dissolved Gas Analysis is a vital test performed on the oil in the transformer. Oil analysis can reveal a variety of phenomena such as arcing, partial discharge, moisture contamination and overheating.. The breakdown of electrical insulating materials and related components inside a transformer generates gases within the unit. Identifying these gases being generated can be very useful information in any preventative maintenance program. Once oil samples have been taken and analyzed, the first step in evaluating DGA results is to consider the concentration levels (in ppm) of each key gas. It is recommended that values for each of the gases be trended over time. Any drastic change is a sign of a potential problem and action should be taken to prevent damage to the transformer.. Keeping trending records and performing regular DGA testing will ensure the health of your transformer and prevent any unscheduled downtime.. ...
Male development and hormones Dr Rob Hicks, BBC HEALTH From its time in the womb right through to old age, the male body is continuously adapting to
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