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Metabolism is the key cellular process of plant physiology. Understanding metabolism and its dynamical behavior under different conditions may help plant biotechnologists to design new cultivars with desired goals. Computational systems biochemistry and incorporation of different omics data unravelled active metabolism and its variations in plants. In this review, we mainly focus on the basics of flux balance analysis (FBA), elementary flux mode analysis (EFMA), and some advanced computational tools. We describe some important results that were obtained using these tools. Limitations and challenges are also discussed. [ABSTRACT FROM AUTHOR]

As in most plants, during their growth from immature to mature stages, the leaves of Setaria viridis, a model C4 bioenergy plant, have differential growth rates from the base (immature or growing) to the tip (most mature). In this study, we constructed a multi-segment C4 leaf metabolic model of S. viridis with two cell types (bundle sheath and mesophyll cells) across four leaf segments (base to tip). We incorporated differential growth rates for each leaf segment as constraints and integrated transcriptomic data as the objective function for our model simulation using flux balance analysis. The model was able to predict the exchanges of metabolites between immature and mature segments of the leaf and the distribution of the activities of biomass synthesis across those segments. Our model demonstrated the use of a modelling approach in studying the source–sink relationship within an organ and provided insights into the metabolic interactions across different parts of a leaf. [ABSTRACT FROM AUTHOR]

Rectifier is the most critical block of the power conditioning circuit designed for the Piezoelectric Energy Harvester (PZEH). Maintaining high rectification efficiency under the variable ambient conditions is the major design challenge. This paper presents a novel topology of self tuned Synchronized Switch Harvesting on Inductor (SSHI) based rectifier circuit for PZEH which provides high power extraction efficiency over a wide range of frequency and magnitude of input vibrations available. The high rectification efficiency is maintained for different PZ devices also. The synchronization of SSHI block under different ambient conditions is achieved by an adaptively controlled pulse generator circuit which uses internal voltage sensing. An active diode circuit to reduce the conduction loss in SSHI block and forward voltage drop of rectifier is used. The proposed circuit is working from 100 to 350 Hz with flipping efficiency above 90% and power extraction efficiency around 50%. A maximum power conversion efficiency of 58 % and maximum flipping efficiency of 93.6% is obtained with a figure of merit of 467% and output power of 72.6 μ W . [ABSTRACT FROM AUTHOR]

Events like melting glaciers, rising sea level, and changing weather patterns are being observed across the globe due to widely reported global warming. The monsoon season rainfall in the North-Western Himalayan region (NWH) becomes more uncertain as there is considerable variation between the duration of the monsoon season and the amount of rainfall during the season. The NWH region receives substantial amount of rainfall and witness various disasters during the monsoon season. In this context, the present study deals with the analysis of the rainfall patterns under various future warming scenarios (2076–2100), namely representative concentration pathway scenario 4.5 (RCP 4.5) and RCP 8.5 (RCP 8.5) with respect to the reference historical time period (1976–2000) during the principal monsoon season (i.e. 1st June to 30th September) of two Indian states (Uttarakhand and Himachal Pradesh) of the NWH region. To serve this purpose, six attributes are defined as follows; start date of the rainy season (SRS), date of the 50% of the seasonal total rainfall (HRS), end date of the rainy season (ERS), length of the rainy season (LRS), 1 day maximum intensity (MRS) and the day corresponding to the maximum rainfall intensity (MDRS). These attributes are estimated for both historical time period and various future warming scenarios based on the archives of five coupled climate models which participated in the Climate Model Inter-comparison Project Phase 5 (CMIP5). Considering huge inter-model variations amongst the CMIP5 models, results are presented here based on the multi-model mean (MME). Characteristics of various attributes of rainfall during the historical time period are compared with that of the two future warming scenarios viz.; RCP 4.5 and RCP 8.5 by means of statistical techniques. There is a possibility of early SRS, delayed ERS and extended LRS along with intense MRS under different future warming scenarios over Himachal Pradesh (HP) as compared with the historical time period; however, results are significant only for 1 day maximum rainfall under RCP 8.5. Similarly, over the Uttarakhand (UK) region, changes in the rainfall pattern are noted under two future warming scenarios viz.; RCP 4.5 and RCP 8.5 as compared with the historical time period; nonetheless, significant changes are noted in MRS and MDRS only under RCP 8.5. It is anticipated that both of the NWH states of HP and UK would experience enhanced MRS under the warmest future warming scenario (i.e. RCP 8.5). Based on the present analysis, intense rainfall events are expected which could act as an initiator for various meteorological hazards over the NWH region in future. [ABSTRACT FROM AUTHOR]

MEMS-based piezoelectric energy harvesters utilize the principle of piezoelectricity for harvesting energy from the ambient vibrations of the environment. These energy harvesters are popular because of their small size. Most of these energy harvesters are constructed using a cantilever beam or plate structure comprising of single or multiple beam or plates. This paper presents the idea of coupling effect present in the piezoelectric multiple-plate cantilever structures. In these multi-plate structures, the fixed ends of plates are connected by a metal layer. We observe that the vibrations of one plate tend to affect the vibrations and output of the neighboring plate. In this paper, we present a qualitative explanation of this coupling effect among the neighboring plates in terms of their electrical and mechanical interaction. Then we present a Finite Element Method Analysis of these multi-plate cantilever structures on COMSOL Multiphysics platform to verify our proposed hypothesis of coupling effect occurring in these structures. [ABSTRACT FROM AUTHOR]

In this paper a new structure of MEMS based piezoelectric (PZ) energy harvester with resonant frequency of 100 Hz is proposed which can be integrated with machine monitoring wireless sensor nodes. Various geometries having different structures of PZ cantilevers have been investigated. The constant length of 5 mm is chosen for all the cantilever beams. A new Perforated Tapered shaped cantilever beam has been proposed. The achieved resonant frequency of the final proposed perforated Tapered structure with proof mass is 101 Hz, which is 27.5% lower than that of the commonly used rectangular structure having same dimensions (including proof mass). The peak voltage output of the proposed structure is 8.5 V which 97% higher than that of the commonly used rectangular structure. [ABSTRACT FROM AUTHOR]

In this paper, modeling of performance parameters and time efficient yet accurate sizing methodology of CMOS analog non-linear circuits have been proposed. The proposed modeling methodology generates empirical models of the non-linear circuit performance parameters in monomial or posynomial form, which is geometric programming (GP) compatible, as a function of the final design variables of the circuit (i.e. the width and length of the transistors). The proposed non-linear circuit sizing methodology, referred to as iterative geometric programming utilizes a correction factor for each of the GP compatible performance parameter models. These correction factors are updated using SPICE simulation after every iteration of the GP optimization. The proposed methodology takes advantage of GP optimization and at the same time it uses SPICE simulation to improve the design point by rectifying inaccuracies that may exists in the GP compatible performance models. Both the proposed methodologies have been validated in a 0.18 μm CMOS technology. The dynamic comparator and the bootstrap switch which are commonly used non-linear circuits in analog-mixed signal systems, have been used as the example circuits. It has been observed that the proposed sizing algorithm converges rapidly and give final design point with SPICE level accuracy higher than 99 %. The efficiency and the accuracy of the proposed algorithm has been numerically compared w.r.t. the sizing algorithm using evolutionary algorithm. It has been observed that the proposed algorithm gives much better results. Moreover, the proposed algorithm is hundreds times faster than that of the evolutionary algorithm. [ABSTRACT FROM AUTHOR]

Background: Growing evidences suggest that microRNAs (miRNAs) can efficiently regulate gene expression at intracellular and extracellular levels. It has been previously reported that plant/food-derived miRNAs are highly enriched in human serum or serum from phytophagous animals, and they are responsible for regulating mammalian gene expression. Thus, miRNAs could function as active signaling molecules, which carry information across distinct species or even kingdoms. However, the mode of miRNA shuttling among various organisms is still a mystery to unravel. The intra and inter kingdom miRNA transfer has boosted up the hypothesis about the potential impact of plant or animal miRNAs on each other. To our knowledge, the software for analyzing cross-kingdom miRNA-targets is lacking.Results: We have developed a web-tool “IIKmTA: Inter and Intra Kingdom miRNA-Target Analyzer” utilizing a database; the data of which have been collected from another web server. Here, user can analyze the targeting potential of (i) plant miRNAs on animal UTRs (Untranslated regions), and vice versa (i.e., inter kingdom), (ii) plant miRNAs on plant UTRs and animal miRNAs on animal UTRs (i.e., intra kingdom). Further, user can analyze (i) miRNAs to targets, (ii) targets to miRNAs, and (iii) miRNA sets targeting sets of targets. For a wide variety of animal and plant species, IIKmTA can identify the miRNA binding sites in the probable target UTRs. Moreover, GC% and AU% of miRNAs will be calculated. All the results can be saved as.csv file.Conclusions: Recent researches identified miRNAs in plants and human secretions and their role in regulating the human genes. Such findings indicate the therapeutic role of secretory miRNAs of such plants which exhibits medicinal value and in near future many diseases may be treated by consumption of these plant miRNAs through food. Using our newly developed database and analyzing tool, one can easily determine the different relationships between miRNAs and their targets across kingdoms. IIKmTA is freely available at http://www.bioinformatics.org/iikmta/. [ABSTRACT FROM AUTHOR]

In the present research, direct metal laser sintering (DMLS) method was chosen to fabricate titanium nitride (TiN) reinforced Ti6Al4V alloy based metal matrix composites (MMCs) under an argon atmosphere using continuous wave (CW) fiber laser having a capacity of 400 W. Laser sintering process parameters, such as layer thickness (0.4 mm), laser beam spot diameter (0.4 mm), and hatching gap (0.2 mm) were kept constant throughout the experiments. Effects of input variable process parameters, such as laser power (50-65 W), scanning speed (3500-4500 mm/min), and volume % of TiN (5-15% v/v) on density, microhardness, and coefficient of friction of the fabricated MMCs were analyzed. The obtained results show the improvement in the physical properties of the fabricated MMCs and FESEM images evidently confirm the presence of TiN particulates and also revealed the uniform distribution of the TiN reinforcement in Ti6Al4V matrix. It was found that the microhardness measured by Vickers test was improved from 388 to 590 HV0.2 with an increase in the volume percentage of TiN. The results showed the coefficient of friction for fabricated samples were in the range of 0.33-0.42. The density (3.40-4.10 g/cm3) of the MMCs was found to increase with increasing the volume percentage of TiN reinforcement in the powder mixture. X-ray diffraction (XRD) analysis of the fabricated MMC confirmed the presence of different in-situ phases, such as Ti, TiN, TiO2, VN, AlV, Ti3Al2N2, and V6N2.7 as a consequence of a series of a chemical reaction between TiN and different elements of Ti6Al4V in the argon atmosphere. [ABSTRACT FROM AUTHOR]

Introduction: For the last two decades, obesity rates have been increasing in both developed and developing countries, with the number of obese women roughly doubling during this period (Stevens et al. in Popul Health Metr 10(1):33, 2012). Obesity represents one of the biggest epidemics of the 21st century. The aim of this retrospective study is to characterise the outcomes of gynaecologic surgeries in cases of extremely obese women with a body mass index (BMI) over 40 kg/m2.Methods: This study is a retrospective case control study in a single-centre setting. Our clinical database was searched for gynaecological operations performed on morbidly obese patients (BMI > 40 kg/m2) between 2009 and 2014 in the Department of Gynaecology and Obstetrics at Hannover Medical School. We matched these results with random patients of normal body weight who had similar surgical procedures and diseases.Results: We included 97 obese patients in our case group and 99 patients in the control group. We found an association between a strongly elevated BMI and peri- and postoperative morbidity. Both intraoperative and postoperative complications are significantly increased in morbid obesity with a BMI over > 40 kg/m2. We observed intraoperative complications in 55.6% and postoperative complications in 50.5% of patients with extreme obesity. In contrast, the complication rate in the control group with a normal BMI was 11% intraoperatively (p = 0.0001) and 3% postoperatively (p = 0.0001). The data showed that perioperative and postoperative morbidity could be reduced by laparoscopic surgery in many cases, with a significant lower rate of difficulties with closing the wound, a significant shorter duration of surgery and a significant lower rate of infections combined with a significant lower reoperation rate and shorter hospital stay. In gynaecological-oncological diseases, we could demonstrate a reduced radicality during the operative procedure due to extreme obesity.Discussion: Dealing with the growing number of obese patients is essential, because the problems emerging from obesity are manifold for the treating hospitals as well as the general health system. For this high-risk patient group, it is indispensable to obtain a thorough overview of the patient's overall situation preoperatively to ensure good perioperative care and complications management. [ABSTRACT FROM AUTHOR]

Objectives: Myomas are defined as benign tumours that arise from smooth muscle cells of the uterus. Clinically, they are found in 5-77% of women of reproductive age. The prevalence rate varies considerably in the literature and a large number of fibroids do not cause symptoms. The lifetime risk of acquiring myomas is 70% for Caucasian women and ≥ 80% for African American women.Materials/methods: The data of 265 patients undergoing surgery for symptomatic myomas by laparoscopy or laparotomy, performed in the gynaecological department of Hannover Medical School, Hannover, Germany, between 2009 and 2013, were retrospectively analysed in this retrospective design study.Results: High pregnancy rates (up to 70%) and birth rates (up to 86%) after myomectomy, regardless of the surgical approach adopted, were found in the current study. The trend was that ≥ 3 myomas and those that were ≥ 6 cm in size were almost always removed by laparotomy in our clinic. It was possible to remove up to 42 myomas without having to perform a hysterectomy. A statistically significant negative correlation was observed in relation to the association between the size of the largest myoma extracted and the pregnancy rate (p = 0.02). A statistically significant correlation between the number of removed myomas and the pregnancy rate was observed for patients who wished to bear children (p = 0.010). Elevated complication rates (of up to 50%) were reported for more than three extracted myomas with a statistically significance (p = 0.0471).Conclusions: It is necessary to ensure sound preoperative selection of the surgical approach in order to achieve the most optimal results, especially for those patients who wished to bear children. [ABSTRACT FROM AUTHOR]

In this paper, an efficient deterministic methodology for generating Pareto-optimal front (PoF) of analog circuits is proposed. The proposed methodology utilizes modified epsilon constraint method along with geometric programming based circuit sizer to determine the Pareto-optimal points (PoPs) of the analog circuits. The generated PoPs are then modeled to generate the PoFs. The efficiency of the proposed methodology and the accuracy of the generated PoF has been verified with respect to that of the commonly used stochastic approach. It is found that to generate PoF having similar spread, the proposed methodology takes only 20 min whereas the stochastic approach takes 60 h. It also has been observed that the accuracy of the generated PoF using the proposed methodology improved by more than 10% with respect to that of the stochastic approach. The proposed methodology has been implemented to generate the PoF of a two-stage Op-Amp, fully differential folded cascode Op-Amp, fully differential single-stage and two-stage Op-Amps. The generated PoFs have been utilized for (1) feasibility checking for a user given specification of an Op-Amp, (2) performance prediction and (3) topology selection of the analog circuit. As per authors' knowledge, this is the first paper which deals with all the aspects, i.e., generation, modeling and application of the PoF of the analog circuits. [ABSTRACT FROM AUTHOR]

Purpose: Laparoscopy is nowadays a well-established surgical method and plays a main role in an ever-increasing range of indications in gynaecology. High-quality studies of surgical techniques are necessary to improve the quality of patient care. The present study aims at evaluating postoperative pain after gynaecological laparoscopy depending on the intraoperative CO2 pressure.Methods: In a prospective, monocentric, randomized single-blind study at the Department of Gynaecology and Obstetrics at the Hannover Medical School, we include patients scheduled for different laparoscopic procedures. Randomization of the intraoperative CO2 pressure was carried out in six groups. Pain was assessed the day after surgery by the blinded nurse using a visual analogue scale.Results: 550 patients were included in the period from May 2013 to January 2016. The analysis of the per protocol population PPP (n = 360) showed no statistically significant difference between the six intervention groups with regard to mean postoperative pain perception. In direct comparison between two groups, an intraoperative CO2 pressure of 15 mmHg was associated with a significant higher pain score than a pressure of 12 mmHg. The difference was 7.46 mm on a 10 cm VAS.Conclusions: The results of our study indicate that a CO2 pressure of 12 versus 15 mmHg can be advantageous. However, the clinical relevance remains unclear due to the low difference in pain. The additional benefit of an even lower pressure of 10 or 8 mmHg cannot be reliably assessed; we found signs of poor visibility conditions in these low pressure groups. [ABSTRACT FROM AUTHOR]

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Chlorophyll is one of the most important pigments present in green plants and rice is one of the major food crops consumed worldwide. We curated the existing genome scale metabolic model (GSM) of rice leaf by incorporating new compartment, reactions and transporters. We used this modified GSM to elucidate how the chlorophyll is synthesized in a leaf through a series of biochemical reactions spanned over different organelles using inorganic macronutrients and light energy. We predicted the essential reactions and the associated genes of chlorophyll synthesis and validated against the existing experimental evidences. Further, ammonia is known to be the preferred source of nitrogen in rice paddy fields. The ammonia entering into the plant is assimilated in the root and leaf. The focus of the present work is centered on rice leaf metabolism. We studied the relative importance of ammonia transporters through the chloroplast and the cytosol and their interlink with other intracellular transporters. Ammonia assimilation in the leaves takes place by the enzyme glutamine synthetase (GS) which is present in the cytosol (GS1) and chloroplast (GS2). Our results provided possible explanation why GS2 mutants show normal growth under minimum photorespiration and appear chlorotic when exposed to air. [ABSTRACT FROM AUTHOR]

Due to socio-economic reasons, it is essential to design efficient stress-tolerant, more nutritious, high yielding rice varieties. A systematic understanding of the rice cellular metabolism is essential for this purpose. Here, we analyse a genome-scale metabolic model of rice leaf using Flux Balance Analysis to investigate whether it has potential metabolic flexibility to increase the biosynthesis of any of the biomass components. We initially simulate the metabolic responses under an objective to maximize the biomass components. Using the estimated maximum value of biomass synthesis as a constraint, we further simulate the metabolic responses optimizing the cellular economy. Depending on the physiological conditions of a cell, the transport capacities of intracellular transporters (ICTs) can vary. To mimic this physiological state, we randomly vary the ICTs' transport capacities and investigate their effects. The results show that the rice leaf has the potential to increase glycine and starch in a wide range depending on the ICTs' transport capacities. The predicted biosynthesis pathways vary slightly at the two different optimization conditions. With the constraint of biomass composition, the cell also has the metabolic plasticity to fix a wide range of carbon-nitrogen ratio. [ABSTRACT FROM AUTHOR]

TNT, accidentally released at several manufacturing sites, contaminates ground water and soil. It has a toxic effect to algae and invertebrate, and chronic exposure to TNT also causes harmful effects to human. On the other hand, many plants including Arabidopsis thaliana have the ability to metabolize TNT either completely or at least to a reduced less toxic form. In A. thaliana, the enzyme UDP glucosyltransferase (UDPGT) can further conjugate the reduced forms 2-HADNT and 4-HADNT (2-hydroxylamino-4, 6- dinitrotoluene and 4-hydroxylamino-2, 6- dinitrotoluene) of TNT. Based on the experimental analysis, existing literature and phylogenetic analysis, it is evident that among 107 UDPGT proteins only six are involved in the TNT degrading process. A total of 13 UDPGT proteins including five of these TNT degrading proteins fall within the same group of phylogeny. Thus, these 13 UDPGT proteins have been classified into two groups, TNT-degrading and TNT-non-degrading proteins. To understand the differences in TNT-degrading capacities; using homology modeling we first predicted two structures, taking one representative sequence from both the groups. Next, we performed molecular docking of the modeled structure and TNT reduced form 2-hydroxylamino-4, 6- dinitrotoluene (2-HADNT). We observed that while the Trp residue located within the active site region of the TNT- degrading protein showed π-Cation interaction; such type of interaction was absent in TNT-non-degrading protein, as the respective Trp residue lay outside of the pocket in this case. We observed the conservation of this π-Cation interaction during MD simulation of TNT-degrading protein. Thus, the position and the orientation of the active site residue Trp could explain the presence and absence of TNT-degrading capacity of the UDPGT proteins. [ABSTRACT FROM AUTHOR]

Objective: Surgeon-controlled endoscope leading assistance systems are a novelty in endoscopic surgery. These systems were evaluated for their applicability and reliability in operative gynecology. In this regard, we evaluated possible methods of operation, operative time, setup time, and comfort for the surgeon, complications, blood transfusions, length of stay, hemoglobin levels, and demographic data. Methods: Two systems with technically identical camera control systems were applied, the SOLOASSIST™ system and the Einstein Vision™ 3D system. The arm systems are attached to the operating table and controlled by surgeon via a manual control, a remote control or a foot switch. Comfort for the surgeon was evaluated using a questionnaire (scale 1-5; 1 'very good', 5 'poor'). All data were collected prospectively in a database (IBM SPSS Statistics 20) and evaluated. Results: One hundred and four patients underwent surgery supported by an active control system. In 43 (41 %) cases, oncological interventions were performed. Average setup time was 7 (3-30) min. There was a significant learning curve regarding the mounting of the system after 20 operations ( p = 0.045). Overall comfort was rated as 'good', divided into control 2.2 (2-4), physical effort 2.1 (1-4), picture quality 1.6 (1-3), and overall satisfaction 2.1 (1-4). About 75 unwanted camera movements were noticed in 104 surgeries. Complications occurred in no case (0 %). Conclusion: The application of an active camera control system was evaluated to be safe for all gynecological laparoscopies. Picture blur is avoided even during prolonged complex procedures. Moreover, the assistant is able to support the surgeon with two instruments, with the result that the presence of a second assistant is not required for complex interventions. Causing only minimal setup time, the examined active control systems improve the effectiveness of surgeries. The physical effort required for the assistant decreases and, by reducing tiring operations and tremor, subsequently, higher precision is reached. [ABSTRACT FROM AUTHOR]

A compensatory mutation (CM) counter balances lethal effects of a deleterious mutation (DM), ensuring the persistence of both through natural selection. However, little is known about the biological aspects of CMs those restore the structural alterations of proteins caused by slightly DMs. Here, by analyzing the evolution of the UDP-glycosyltransferase 73B4 protein among monocot-dicot plants, we investigate the occurrence of CMs around slightly DMs in 3D space. Our results illustrate that CMs exhibit significantly higher tendency to occur within the range of electrostatic interaction around the slightly DMs, compared to occurring randomly in the protein. [ABSTRACT FROM AUTHOR]