Feedback Regulation System Research Articles

Building Feedback-Regulation System Through Atomic Design for Highly Active SO2 Sensing.

Reasonably constructing an atomic interface is pronouncedly essential for surface-related gas-sensing reaction. Herein, we present an ingenious feedback-regulation system by changing the interactional mode between single Pt atoms and adjacent S species for high-efficiency SO2 sensing. We found that the single Pt sites on the MoS2 surface can induce easier volatilization of adjacent S species to activate the whole inert S plane. Reversely, the activated S species can provide a feedback role in tailoring the antibonding-orbital electronic occupancy state of Pt atoms, thus creating a combined system involving S vacancy-assisted single Pt sites (Pt-Vs) to synergistically improve the adsorption ability of SO2 gas molecules. Furthermore, in situ Raman, ex situ X-ray photoelectron spectroscopy testing and density functional theory analysis demonstrate the intact feedback-regulation system can expand the electron transfer path from single Pt sites to whole Pt-MoS2 supports in SO2 gas atmosphere. Equipped with wireless-sensing modules, the final Pt1-MoS2-def sensors array can further realize real-time monitoring of SO2 levels and cloud-data storage for plant growth. Such a fundamental understanding of the intrinsic link between atomic interface and sensing mechanism is thus expected to broaden the rational design of highly effective gas sensors.

Meta-Modulation: A General Learning Framework for Cross-Task Adaptation.

Building learning systems possessing adaptive flexibility to different tasks is critical and challenging. In this article, we propose a novel and general meta-learning framework, called meta-modulation (MeMo), to foster the adaptation capability of a base learner across different tasks where only a few training data are available per task. For one independent task, MeMo proceeds like a "feedback regulation system", which achieves an adaptive modulation on the so-called definitive embeddings of query data to maximize the corresponding task objective. Specifically, we devise a type of efficient feedback information, definitive embedding feedback (DEF), to mathematize and quantify the unsuitability between the few training data and the base learner as well as the promising adjustment direction to reduce this unsuitability. The DEFs are encoded into high-level representation and temporarily stored as task-specific modulator templates by a modulation encoder. For coming query data, we develop an attention mechanism acting upon these modulator templates and combine both task/data-level modulation to generate the final data-specific meta-modulator. This meta-modulator is then used to modulate the query's embedding for correct decision-making. Our framework is scalable for various base learner models like multi-layer perceptron (MLP), long short-term memory (LSTM), convolutional neural network (CNN), and transformer, and applicable to different learning problems like language modeling and image recognition. Experimental results on a 2-D point synthetic dataset and various benchmarks in language and vision domains demonstrate the effectiveness and competitiveness of our framework.

Ways of penetration of glucocorticosteroids from the tympanic cavity to the structures of the inner ear: A review

To date, in domestic and foreign literature, there are more and more reports of the successful use of glucocorticosteroids for the treatment of pathology of the inner ear by local intratympanic administration. Many methods are being developed to deliver drugs to the structures of the inner ear. As you know, the systemic administration of glucocorticosteroids has a number of contraindications and a large number of side effects, due to a wide spectrum of action. Exogenous glucocorticoids disrupt the natural balance of the hypothalamic-pituitary-adrenal system, interfering with the negative feedback regulation system, which requires a long time to fully restore. The intratympanic method of administering glucocorticosteroids makes it possible to bypass the above undesirable effects and at the same time provide the desired therapeutic effect on the vestibular and cochlear structures of the inner ear. With regard to the effect on the structures of the inner ear, intratympanic use of glucocorticosteroids turned out to be more effective than the systemic one, which is associated with the presence of a hematoperilymphatic barrier, comparable in its permeability to the blood-brain barrier. Moreover, when administered systemically, large doses of steroids are required to achieve a sufficient concentration of the drug in the fluids of the inner ear. To date, many questions remain regarding the routes by which the drug penetrates to the structures of the inner ear, the principles of distribution of the drug within the cochlear fluids, as well as the anatomical obstacles that may be encountered on the way to achieving the desired therapeutic effect. The purpose of this article is to highlight the current achievements in the field of research on the routes of penetration of drugs, in particular glucocorticosteroids, to the structures of the inner ear from the tympanic cavity.

Study on Layered-Backfill-Based Water Protection Technology of Thick Coal Seam in the Ecologically Fragile Mining Area in Western China

The mining areas in Western China are characterized by water shortage and ecological fragility, and the coal resources in these areas are extracted in a large-scale and highly intensive manner, which is highly likely to induce ecological problems, such as soil erosion and grassland degradation. In addition, there is a secondary protection zone of Hongshixia water source near Guojiatan minefield. If the water resources loss of Salawusu Formation is too large, it will affect the normal water supply of Yulin city. To reasonably coordinate coal exploitation and water protection, the development characteristics of water-conducted fissures with different backfill ratios are obtained in combination with theoretical analysis, field test, and numerical modelling. The panel layout of the layered-backfill-based water protection working face and the parallel operation of mining and backfilling are designed, and a feedback regulation system integrating hydrological monitoring and backfill ratios is established, which assists in evaluating the effectiveness of water protection. The results indicated that when the slicing mining method was adopted with the roof naturally caving, the maximum development height of the water conducted fracture zone was 220.0 m (developed to the Yan’an Formation), and the water conducted fracture zone could only develop to the Yan’an Formation without crossing the Zhiluo Formation when the backfill ratio reached 80%. The water emission rates in the west of the field testing area reduced from 334.95 m3/h to 60.60 m3/h, dropping by 86.86%. Compared to the scene prior to the layered backfill mining, the shallow water outflow was reduced by 72.74 m3/h, and it helped annually reduce the shallow water loss of 637200 m3, which was equivalent to 1.74% of the actual water supply to Yunli city every year. The results of this study can provide guidance on effectively avoiding the loss of shallow water resources that are regarded as indispensable sources of domestic water.

Feedback regulation system for spraying parameters based on online droplet mass deposit measurements

In order to effectively optimize and regulate spraying parameters based on actual spraying performance and improve pesticide utilization rate, in this research, a feedback regulation system for the regulation of spraying parameters was designed based on droplet mass deposit online measurement. The system consisted of an online droplet mass deposit measurement module, wireless transmission module, decision module, and spraying parameters regulation module. First, the droplet mass deposits on the sampling points were measured. Based on the deviation between the measured and expected droplet mass, the expected spraying parameters were determined by the decision module. The spraying parameter was regulated to the expected value by regulating the pulse duty cycle on the pump motor using a micro control unit and a relay. Evaluation tests were conducted indoors using an indoor spraying platform and outdoors using an unmanned aerial vehicle. The results showed that the relative errors between the expected and measured droplet mass deposit after regulation were 6.84% and 11.48% for the indoor and outdoor tests, respectively. Therefore, an optimal spraying performance was observed after regulation. This research provided an experimental platform to quickly optimize spraying parameters and also provided technical references for precision spraying. Keywords: spray, droplet mass deposit, online measurement, wireless transmission, duty cycle, feedback regulation DOI: 10.25165/j.ijabe.20221502.6118 Citation: Sun C D, Qiu W. Feedback regulation system for spraying parameters based on online droplet mass deposit measurements. Int J Agric & Biol Eng, 2022; 15(2): 25–29.

Cultivation of Saccharomyces cerevisiae with Feedback Regulation of Glucose Concentration Controlled by Optical Fiber Glucose Sensor.

Glucose belongs among the most important substances in both physiology and industry. Current food and biotechnology praxis emphasizes its on-line continuous monitoring and regulation. These provoke increasing demand for systems, which enable fast detection and regulation of deviations from desired glucose concentration. We demonstrated control of glucose concentration by feedback regulation equipped with in situ optical fiber glucose sensor. The sensitive layer of the sensor comprises oxygen-dependent ruthenium complex and preimmobilized glucose oxidase both entrapped in organic–inorganic polymer ORMOCER®. The sensor was placed in the laboratory bioreactor (volume 5 L) to demonstrate both regulations: the control of low levels of glucose concentrations (0.4 and 0.1 mM) and maintenance of the glucose concentration (between 2 and 3.5 mM) during stationary phase of cultivation of Saccharomyces cerevisiae. Response times did not exceed 6 min (average 4 min) with average deviation of 4%. Due to these regulation characteristics together with durable and long-lasting (≥2 month) sensitive layer, this feedback regulation system might find applications in various biotechnological processes such as production of low glucose content beverages.

Interplay among miR-29 family, mineral metabolism, and gene regulation in Bos indicus muscle.

An interplay between gene expression, mineral concentration, and beef quality traits in Bos indicus muscle has been reported previously under a network approach. However, growing evidence suggested that miRNAs not only modulate gene expression but are also involved with mineral homeostasis. To our knowledge, understanding of the miRNA-gene expression-mineral concentration relationship in mammals is still minimal. Therefore, we carried out a miRNA co-expression and multi-level miRNA-mRNA integration analyses to predict the putative drivers (miRNAs and genes) associated with muscle mineral concentration in Nelore steers. In this study, we identified calcium and iron to be the pivotal minerals associated with miRNAs and gene targets. Furthermore, we identified the miR-29 family (miR-29a, -29b, -29c, -29d-3p, and -29e) as the putative key regulators modulating mineral homeostasis. The miR-29 family targets genes involved with AMPK, insulin, mTOR, and thyroid hormone signaling pathways. Finally, we reported an interplay between miRNAs and minerals acting cooperatively to modulate co-expressed genes and signaling pathways both involved with mineral and energy homeostasis in Nelore muscle. Although we provided some evidence to understand this complex relationship, future work should determine the functional implications of minerals for miRNA levels and their feedback regulation system.\\An interplay between gene expression, mineral concentration, and beef quality traits in Bos indicus muscle has been reported previously under a network approach. However, growing evidence suggested that miRNAs not only modulate gene expression but are also involved with mineral homeostasis. To our knowledge, understanding of the miRNA-gene expression-mineral concentration relationship in mammals is still minimal. Therefore, we carried out a miRNA co-expression and multi-level miRNA-mRNA integration analyses to predict the putative drivers (miRNAs and genes) associated with muscle mineral concentration in Nelore steers. In this study, we identified calcium and iron to be the pivotal minerals associated with miRNAs and gene targets. Furthermore, we identified the miR-29 family (miR-29a, -29b, -29c, -29d-3p, and -29e) as the putative key regulators modulating mineral homeostasis. The miR-29 family targets genes involved with AMPK, insulin, mTOR, and thyroid hormone signaling pathways. Finally, we reported an interplay between miRNAs and minerals acting cooperatively to modulate co-expressed genes and signaling pathways both involved with mineral and energy homeostasis in Nelore muscle. Although we provided some evidence to understand this complex relationship, future work should determine the functional implications of minerals for miRNA levels and their feedback regulation system.

Brucella Infection Regulates Thioredoxin-Interacting Protein Expression to Facilitate Intracellular Survival by Reducing the Production of Nitric Oxide and Reactive Oxygen Species.

Thioredoxin-interacting protein (TXNIP) is a multifunctional protein that functions in tumor suppression, oxidative stress, and inflammatory responses. However, how TXNIP functions during microbial infections is rarely reported. In this study, we demonstrate that Brucella infection decreased TXNIP expression to promote its intracellular growth in macrophages by decreasing the production of NO and reactive oxygen species (ROS). Following Brucella abortus infection, TXNIP knockout RAW264.7 cells produced significantly lower levels of NO and ROS, compared with wild-type RAW264.7 cells. Inducible NO synthase (iNOS) inhibitor treatment reduced NO levels, which resulted in a dose-dependent restoration of TXNIP expression, demonstrating that the expression of TXNIP is regulated by NO. In addition, the expression of iNOS and the production of NO were dependent on the type IV secretion system of Brucella Moreover, Brucella infection reduced TXNIP expression in bone marrow-derived macrophages and mouse lung and spleen. Knocked down of the TXNIP expression in bone marrow-derived macrophages increased intracellular survival of Brucella These findings revealed the following: 1) TXNIP is a novel molecule to promote Brucella intracellular survival by reducing the production of NO and ROS; 2) a negative feedback-regulation system of NO confers protection against iNOS-mediated antibacterial effects. The elucidation of this mechanism may reveal a novel host surveillance pathway for bacterial intracellular survival.

Regulated hAAT Expression from a Novel rAAV Vector and Its Application in the Prevention of Type 1 Diabetes.

We, and others, have previously achieved high and sustained levels of transgene expression from viral vectors, such as recombinant adeno-associated virus (rAAV). However, regulatable transgene expression may be preferred in gene therapy for diseases, such as type 1 diabetes (T1D) and rheumatoid arthritis (RA), in which the timing and dosing of the therapeutic gene product play critical roles. In the present study, we generated a positive feedback regulation system for human alpha 1 antitrypsin (hAAT) expression in the rAAV vector. We performed quantitative kinetics studies in vitro and in vivo demonstrating that this vector system can mediate high levels of inducible transgene expression. Transgene induction could be tailored to occur rapidly or gradually, depending on the dose of the inducing drug, doxycycline (Dox). Conversely, after withdrawal of Dox, the silencing of transgene expression occurred slowly over the course of several weeks. Importantly, rAAV delivery of inducible hAAT significantly prevented T1D development in non-obese diabetic (NOD) mice. These results indicate that this Dox-inducible vector system may facilitate the fine-tuning of transgene expression, particularly for hAAT treatment of human autoimmune diseases, including T1D.

Design of the Voltage Measurement and Feedback Regulation System of 100-kV High-Voltage Power Supply on J-TEXT Tokamak

A 100-kV/60-A high-voltage power supply (HVPS) based on pulse step modulation (PSM) technology has been established on J-TEXT Tokamak to feed the electron cyclotron resonance heating (ECRH) system for plasma heating. To fulfill the waveform monitoring, feedback regulation, and protection requirements, a high speed and precision voltage measurement and transmission system with high voltage and ground isolation is designed and applicated to the HVPS. A feedback regulation method is proposed to not only suppress the output voltage overshoot during startup of the HVPS operation but also ensure the precision of the output voltage on flat stage under the change of load conditions. Experiment results on the J-TEXT HVPS show that the voltage measurement system behaves well both in precision (measurement error $ ). The feedback regulation method can reduce the overshoot voltage to less than 1%.

Dysregulation of hypothalamic-pituitary estrogen receptor α-mediated signaling causes episodic LH secretion and cystic ovary.

Polycystic ovary syndrome (PCOS) is a hypothalamic-pituitary-gonadal (HPG) axis disorder. PCOS symptoms most likely result from a disturbance in the complex feedback regulation system of the HPG axis, which involves gonadotrophic hormones and ovarian steroid hormones. However, the nature of this complex and interconnecting feedback regulation makes it difficult to dissect the molecular mechanisms responsible for PCOS phenotypes. Global estrogen receptor α (ERα) knockout (KO) mice exhibit a disruption of the HPG axis, resulting in hormonal dysregulation in which female ERα KO mice have elevated levels of serum estradiol (E2), testosterone, and LH. The ERα KO females are anovulatory and develop cystic hemorrhagic ovaries that are thought to be due to persistently high circulating levels of LH from the pituitary. However, the role of ERα in the pituitary is still controversial because of the varied phenotypes reported in pituitary-specific ERα KO mouse models. Therefore, we developed a mouse model where ERα is reintroduced to be exclusively expressed in the pituitary on the background of a global ERα-null (PitERtgKO) mouse. Serum E2 and LH levels were normalized in PitERtgKO females and were comparable to wild-type serum levels. However, the ovaries of PitERtgKO adult mice displayed a more overt cystic and hemorrhagic phenotype when compared with ERα KO littermates. We determined that anomalous sporadic LH secretion caused the severe ovarian phenotype of PitERtgKO females. Our observations suggest that pituitary ERα is involved in the estrogen negative feedback regulation, whereas hypothalamic ERα is necessary for the precise control of LH secretion. Uncontrolled, irregular LH secretion may be the root cause of the cystic ovarian phenotype with similarities to PCOS.-Arao, Y., Hamilton, K. J., Wu, S.-P., Tsai, M.-J., DeMayo, F. J., Korach, K. S. Dysregulation of hypothalamic-pituitary estrogen receptor α-mediated signaling causes episodic LH secretion and cystic ovary.

Resting zone of the growth plate houses a unique class of skeletal stem cells.

SummarySkeletal stem cells regulate bone growth and homeostasis by generating diverse cell types including chondrocytes, osteoblasts and marrow stromal cells. The emerging model postulates a distinct type of skeletal stem cells closely associated with the growth plate1-4, a special cartilaginous tissue playing critical roles in bone elongation5. The resting zone maintains the growth plate by expressing parathyroid hormone-related protein (PTHrP) that interacts with Indian hedgehog (Ihh) released from the hypertrophic zone6-10, while providing a source of other chondrocytes11. However, the identity of skeletal stem cells and how they are maintained in the growth plate are unknown. Here we show that skeletal stem cells are formed among PTHrP+ chondrocytes within the resting zone of the postnatal growth plate. PTHrP+ chondrocytes expressed a panel of markers for skeletal stem/progenitor cells and uniquely possessed the properties as skeletal stem cells in cultured conditions. Cell lineage analysis revealed that PTHrP+ resting chondrocytes continued to form columnar chondrocytes long term, which underwent hypertrophy and became osteoblasts and marrow stromal cells beneath the growth plate. Transit-amplifying chondrocytes in the proliferating zone, which was concertedly maintained by a forward signal from undifferentiated cells (PTHrP) and a reverse signal from hypertrophic cells (Ihh), provided instructive cues to maintain cell fates of PTHrP+ resting chondrocytes. Our findings unravel a unique somatic stem cell type that is initially unipotent and acquires multipotency at the post-mitotic stage, underscoring the malleable nature of the skeletal cell lineage. This system provides a model in which functionally dedicated stem cells and their niche are specified postnatally and maintained throughout tissue growth by a tight feedback regulation system.

Burden-driven feedback control of gene expression.

Cells use feedback regulation to ensure robust growth despite fluctuating demands for resources and differing environmental conditions. However, the expression of foreign proteins from engineered constructs is an unnatural burden that cells are not adapted for. Here we combined RNA-seq with an in vivo assay to identify the major transcriptional changes that occur in Escherichia coli when inducible synthetic constructs are expressed. We observed that native promoters related to the heat-shock response activated expression rapidly in response to synthetic expression, regardless of the construct. Using these promoters, we built a dCas9-based feedback-regulation system that automatically adjusts the expression of a synthetic construct in response to burden. Cells equipped with this general-use controller maintained their capacity for native gene expression to ensure robust growth and thus outperformed unregulated cells in terms of protein yield in batch production. This engineered feedback is to our knowledge the first example of a universal, burden-based biomolecular control system and is modular, tunable and portable.

The impact of variable cost on a dynamic Cournot–Stackelberg game with two decision-making stages

This paper analyses a dynamic model of Cournot–Stackelberg which involves a feedback regulation system based on the costs of production. The manufacturer makes decisions based on costs of production and wholesale prices as the leader of the market, while the retailers make decisions according to order amount. The decision-making process of the system is divided into two stages in order to carry out the research more clearly and the doubling period bifurcation will occur with speed of adjusting decision-making increase. It is proved that the stability of the model can be considered separately into two decision-making processes, the cross-effects of the two decision-making stages are analyzed. The manufacturer's decision-making has a decisive influence on the stability of the whole system when the manufacturer is a marketing leader and the parameters also have a significant effect on the stability of the system. Finally, the paper proposes a chaos control method based on adaptive method, which is inspired by decision-making methods. The result of the paper has great significance to the Cournot–Stackelberg game with variable costs and master-slave status.

LOB DOMAIN-CONTAINING PROTEIN 15 Positively Regulates Expression of VND7, a Master Regulator of Tracheary Elements.

Xylem includes xylem parenchyma cells, fibers and tracheary elements. Differentiation of tracheary elements is an irreversible process that is controlled by the master regulator VASCULAR-RELATED NAC-DOMAIN 7 (VND7). Molecular events occurring downstream of VND7 are well understood, but little is known regarding upstream regulation of VND7. In this study, we identified LOB DOMAIN-CONTAINING PROTEIN 15 (LBD15)/ASYMMETRIC LEAVES2-LIKE (ASL11) as a regulator of VND7. LBD15 was expressed in immature vascular cells and positively regulated both VND7 expression and differentiation of tracheary elements. LBD15 directly associated with the upstream sequence of VND7 and positively regulated VND7 expression. A 25 bp upstream sequence was essential for VND7 expression in the elongation zone of Arabidopsis roots. Taken together with previous studies identifying LBD15 as a target of VND7, we propose that LBD15 acts in a positive feedback regulation system that promotes and accelerates VND7 expression during the initiation phase of tracheary element differentiation in roots.

A multichannel microcalorimetric system

A new generation isothermal multichannel microcalorimetry system based on an earlier reported system which has been commercialised under the name “Thermal Activity Monitor” (TAM) is described and evaluated. The system has a modular design constituting a thermostat that accommodates up to four calorimetric units. The temperature stability of the thermostat has been improved 100-fold compared to the original TAM mainly due to novel technology for absolute temperature measurements consisting of a platinum resistance sensor combined with a high-resolution thermoelectric (TE) module housed in an aluminium body for temperature fluctuation measurements. In combination with the continuous liquid overflow design similar to that of the original TAM with an inbuilt Peltier cooling/heating system forming part of a single feedback regulation system, temperature drifts/fluctuations over 24 h better than ±10 µK have been achieved. Besides the isothermal mode, the thermostat can be controlled to perform temperature ramps with rates from close to 0 up to 2 K h−1. Two basic designs of twin heat flow calorimeters are described. One is similar to those originally reported having the sample and reference sides mirrored horizontally, and with a solid heat sink time constant of 6000 s. The other has the sample and reference mirrored on the vertical axis with a solid heat sink time constant of 500 s making it considerably smaller. Both calorimeters are equipped with insertion ampoule holders that can hold 4 mL reaction volume. The lowest observed long-term signal stability among a population of data from the two calorimeters was ±17 nW/24 h for the calorimeter with the larger heat sink and ±50 nW/24 h for the calorimeter with the smaller heat sink. Test experiments indicated the absence of significant systematic errors for the former calorimeter type while a maximum of 2–3% error was observed for the latter type. This difference between the two calorimeter types was attributed to different positioning of the TE sensors relative to the calibration heater.

Transcriptional expression of seven key genes involved in steroidal glycoalkaloid biosynthesis in potato microtubers

Red light (10–12 lx) has been shown to induce the accumulation of steroidal glycoalkaloids (SGA) in potato (Solanum tuberosum) tubers. This study was to analyse the impact of genotypes, red light illumination and duration of incubation on SGA biosynthesis at the transcriptional level. The microtubers of wild species S. chacoense and cultivated potato varieties Shepody, Favorita, Longshu-3 and Zhuangshu-3 were tested. After 24 h incubation in the dark, the genes coding for hydroxymethylglutaryl coenzyme A reductase (hmg1, hmg2) and squalene synthase (pss1) remained relatively stable in S. chacoense and Longshu-3. The gene coding for vetispiradiene synthase (pvs1) was significantly induced in Favorita and Longshu-3. The expressions of sgt1 (solanidine galactosyl transferase) and sgt3 (rhamnosyltransferase) were induced in all tested varieties except S. chacoense. The transcript abundance of hmg1, hmg2, sgt1 and sgt3 was increased with red light illumination and incubation duration, but pvs1 was decreased. The results imply a feedback regulation system at the transcriptional level in SGA biosynthesis during red light illumination.

Salicylic acid 3-hydroxylase regulates Arabidopsis leaf longevity by mediating salicylic acid catabolism

The plant hormone salicylic acid (SA) plays critical roles in plant defense, stress responses, and senescence. Although SA biosynthesis is well understood, the pathways by which SA is catabolized remain elusive. Here we report the identification and characterization of an SA 3-hydroxylase (S3H) involved in SA catabolism during leaf senescence. S3H is associated with senescence and is inducible by SA and is thus a key part of a negative feedback regulation system of SA levels during senescence. The enzyme converts SA (with a Km of 58.29 µM) to both 2,3-dihydroxybenzoic acid (2,3-DHBA) and 2,5-DHBA in vitro but only 2,3-DHBA in vivo. The s3h knockout mutants fail to produce 2,3-DHBA sugar conjugates, accumulate very high levels of SA and its sugar conjugates, and exhibit a precocious senescence phenotype. Conversely, the gain-of-function lines contain high levels of 2,3-DHBA sugar conjugates and extremely low levels of SA and its sugar conjugates and display a significantly extended leaf longevity. This research reveals an elegant SA catabolic mechanism by which plants regulate SA levels by converting it to 2,3-DHBA to prevent SA overaccumulation. The research also provides strong molecular genetic evidence for an important role of SA in regulating the onset and rate of leaf senescence.

Study on Real-Time Regulation of Water Resources Yellow River Basin

This paper puts forward and studies the concept, features as well as regulation process of real-time dispatch of basin water resources. The real-time regulation of basin water resources features temporal regulation system of multiple time-step nesting, dynamic balance regulation system of self-adapting demand-supply, dynamic information-based feedback regulation system, and three-element regulation system in combination of reservoir dispatch, river reach water distribution and flow forecast control. With example of lower Yellow River reaches below Xiaolangdi, a real-time regulation model of water resources in river basin with multiple time-step nesting and scrolling-amendment has been developed. The developed model has been put into actual practice and resulted in the safety of water supply and avoid of dry-up in consecutive low flow yeas of Yellow River Basin.

Rabeprazole delays gastric emptying of a nutrient liquid

It is generally considered that gastric acid suppression delays gastric emptying of solid meals because gastric hypoacidity impairs peptic digestion and antral triturition. Rabeprazole is one of the most potent acid suppressants. We conducted this cross-over study to investigate if rabeprazole delays gastric emptying of liquid nutrients, for which peptic digestion is unnecessary. On two randomized occasions, 13 healthy male volunteers underwent the (13)C-acetate breath test following ingestion of a 300 kcal-liquid meal. On one occasion, they had received 20 mg rabeprazole for the preceding 2 days and 1 h before the test. On another, they took no pretreatment. Based on 4 h breath samples, the half (13)CO(2) excretion time (t(1/2b)) and the time of maximal excretion (t(max)) were calculated as overall measures of gastric emptying. In addition, time profiles of gastric emptying were generated using the Wagner-Nelson analytical method, which creates the gastric emptying curve as accurately as the scintigraphy. Rabeprazole significantly prolonged t(max) but unchanged t(1/2b). The gastric emptying profiles showed that rabeprazole evoked a segmental slowing of gastric emptying during 0.5-1.25 h of post-meal ingestion. Rabeprazole suppresses gastric emptying of a liquid nutrient 0.5 h after meal ingestion. We have speculated that: (i) rabeprazole delays gastric emptying via a mechanism other than acid-pepsin maldigestion; and (ii) rabeprazole may intensify the post-gastric feedback regulation system (>0.5 h of post-meal).