Continuous high-frequency pesticide monitoring to observe the unexpected and the overlooked.

Synthetic Plant Protection Products (PPPs) are a key element for a large part of today's global food systems. However, the transport of PPPs and their transformation products (TPs) to water bodies has serious negative effects on aquatic ecosystems. Small streams in agricultural catchments may experience pronounced concentration peaks given the proximity to fields and poor dilution capacity. Traditional sampling approaches often prevent a comprehensive understanding of PPPs and TPs concentration patterns being limited by trade-offs between temporal resolution and duration of the observation period. These limitations result in a knowledge gap for accurate ecotoxicological risk assessment and the achievement of optimal monitoring strategies for risk mitigation. We present here high-frequency PPPs and TPs concentration time-series measured with the autonomous MS2Field platform that combines continuous sampling and on-site measurements with a high-resolution mass spectrometer, which allows for overcoming temporal trade-offs. In a small agricultural catchment, we continuously measured 60 compounds at 20 minutes resolution for 41 days during the growing season. This observation period included 8 large and 15 small rain events and provided 2560 concentration values per compound. To identify similarities and differences among the compound-specific concentration time-series, we analysed the entire dataset with positive matrix factorisation. Six factors sufficiently captured the overall complexity in concentration dynamics. While one factor reflected dilution during rainfall, five factors identified PPPs groups that seemed to share a common history of recent applications. The investigation per event of the concentration time-series revealed a surprising complexity of dynamic patterns; physico-chemical properties of the compounds did not influence the (dis)similarity of chemographs. Some PPPs concentration peaks led while others lagged by several hours the water level peaks during large events. During small events, water level peaks always preceded concentration peaks, which were generally only observed when the water levels had almost receded to pre-event levels. Thus, monitoring schemes relying on rainfall or water level as proxies for triggering sampling may lead to systematic biases. The high temporal resolution revealed that the Swiss national monitoring integrating over 3.5 days underestimated critical concentration peaks by a factor of eight to more than 32, captured 3 out of 11 exceedances of legal acute quality standards (the relevant values in the Swiss Water Protection Law) and recorded 1 out of 9 exceedances of regulatory acceptable concentrations (the relevant values for the PPPs registration process). MS2Field allowed for observing unexpected and overlooked pesticide dynamics with consequences for further research but also for monitoring. The large variability in timing of concentration peaks relative to water level calls for more in-depth analyses regarding the respective transport mechanisms. To perform these analyses, spatially distributed sampling and time-series of geo-referenced PPPs application data are needed.

The COVID-19 pandemic: growth patterns, power law scaling, and saturation.

More and more countries are showing a significant slowdown in the number of new COVID-19 infections due to effective governmentally instituted lockdown and social distancing measures. We have analyzed the growth behavior of the top 25 most affected countries by means of a local slope analysis and found three distinct patterns that individual countries follow depending on the strictness of the lockdown protocols: rise and fall, power law, or logistic. For countries showing power law growth we have determined the scaling exponents. For countries that showed a strong slowdown in the rate of infections we have extrapolated the expected saturation of the total number of infections and the expected final date. Three different extrapolation methods (logistic, parabolic, and cutoff power law) were used. All methods agree on the order of magnitude of saturation and end dates. Global infection rates are analyzed with the same methods. The relevance and accuracy of these extrapolations is discussed.

In silico and in vitro evaluation of the impact of mutations in non-severe haemophilia A patients on assay discrepancies.

Haemophilia A (HA) is caused by a lack or reduced amount of factor VIII protein (FVIII). About one-third of patients with non-severe HA carrying specific missense mutations show discrepant results between FVIII activity (FVIII:C), measured by one-stage or chromogenic two-stage assays. The aim of this study was to elucidate the mechanism underlying the assay discrepancy in vitro and in silico. Thirteen missense mutations in the Factor 8-gene associated with discrepant results in patients were transiently expressed. FVIII:C of the mutations was determined using two one-stage assays (FVIII:C1st, FVIII:CBonn) and a two-stage chromogenic assay (FVIII:Cchr). Furthermore, thrombin generation test (TGT) and in silico analysis were performed to investigate the haemostatic potential as well as the structural impact of the variants, respectively. For the majority (9/13) of the analysed mutations, the discrepancy was confirmed. Moreover, we established a modified TGT protocol for in vitro characterization of FVIII. Hence, TGT parameters were significantly impaired in the group of variants associated with higher chromogenic values. Additionally, in silico analysis revealed the impact of the mutations on FVIII protein structure leading to assay discrepancy. Moreover, the data shows that also among one-stage clotting assays, assay discrepancy is observed. Our results show that for the majority of mutations, application of a global assay like TGT method could help to improve diagnosis or correct assessment of the severity of HA.

The Space Physics Environment Data Analysis System (SPEDAS).

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

Comparison of different types of landfill leachate treatments by employment of nontarget screening to identify residual refractory organics and principal component analysis.

Three different chemical oxidation processes were investigated in terms of their capability to degrade organic chemical components of real mature landfill-leachate in combination with biological treatment run in a Sequencing Batch Biofilter Granular Reactor (SBBGR). H2O2, H2O2 + UV and O3 were integrated with SBBGR and respective effluents were analyzed and compared with the effluent obtained from biological SBBGR treatment alone. In agreement with their respective oxidative power, conventional bulk parameters (residual COD, TOC, Ntot, TSS) determined from the resulting effluents evidenced the following efficacy ranking for degradation: SBBGR/O3 > SBBGR/UV + H2O2 > SBBGR/H2O2 > SBBGR. A more detailed characterization of the organic compounds was subsequently carried out for the four treated streams. For this, effluents were first subjected to a sample preparation step, allowing for a classification in terms of acidic, basic, strongly acidic and strongly basic compounds, and finally to analysis by liquid chromatography/high resolution mass spectrometry (LC/HR-MS). This classification, combined with further data post-processing (non-target screening, Venn Diagram, tri-dimensional plot and Principal Component Analysis), evidenced that the SBBGR/H2O2 process is comparable to the pure biological oxidation. In contrast, SBBGR/O3 and SBBGR/UV + H2O2 not only resulted in a very different residual composition as compared to SBBGR and SBBGR/H2O2, but also differ significantly from each other. In fact, and despite of the SBBGR/O3 being the most efficient process, this treatment remained chemically more similar to SBBGR/H2O2 than to SBBGR/UV + H2O2. This finding may be attributable to different mechanism of degradation involved with the use of UV radiation. Apart from these treatment differences, a series of recalcitrant compounds was determined in all of the four treatments and partly identified as hetero-poly-aromatic species (humic acids-like species).

Systematic dimensional reduction of the layered ß-FeSe structure by solvothermal synthesis.

Dimensional reduction of superconducting anti PbO-type iron selenide has been achieved by terminating the tetragonal square layers of FeSe4/4 tetrahedra by ethylenediamine (en) ligands. We obtained three new structures in the Fe-Se-en system. Fe3Se4(en)3 contains FeSe2 single chains bridged via Fe(en)3 complexes. Fe10Se12(en)7 has Fe2Se3 double strands separated by Fe(en)3 complexes and free en molecules. Fe0.85Se(en)0.3 conserves the tetragonal layers of bulk FeSe which are now widely separated by en molecules. Through systematic dilution of the solvent we were able to introduce an additional parameter in solvothermal synthesis and thus have control over the connectivity of the tetrahedra. Additionally, a phase diagram of the Fe-Se-en system is generated by variation of the reaction temperature. The magnetic properties of the FeSe derivatives range from superconductivity and antiferromagnetism to paramagnetism.

Global observations of magnetospheric high-m poloidal waves during the 22 June 2015 magnetic storm.

We report global observations of high-m poloidal waves during the recovery phase of the 22 June 2015 magnetic storm from a constellation of widely spaced satellites of five missions including Magnetospheric Multiscale (MMS), Van Allen Probes, Time History of Events and Macroscale Interactions during Substorm (THEMIS), Cluster, and Geostationary Operational Environmental Satellites (GOES). The combined observations demonstrate the global spatial extent of storm time poloidal waves. MMS observations confirm high azimuthal wave numbers (m ~ 100). Mode identification indicates the waves are associated with the second harmonic of field line resonances. The wave frequencies exhibit a decreasing trend as L increases, distinguishing them from the single-frequency global poloidal modes normally observed during quiet times. Detailed examination of the instantaneous frequency reveals discrete spatial structures with step-like frequency changes along L. Each discrete L shell has a steady wave frequency and spans about 1 RE , suggesting that there exist a discrete number of drift-bounce resonance regions across L shells during storm times.

Ca2+/Calmodulin-Dependent Protein Kinase II in Vascular Smooth Muscle.

Ca2+-dependent signaling pathways are central regulators of differentiated vascular smooth muscle (VSM) contractile function. In addition, Ca2+ signals regulate VSM gene transcription, proliferation, and migration of dedifferentiated or "synthetic" phenotype VSM cells. Synthetic phenotype VSM growth and hyperplasia are hallmarks of pervasive vascular diseases including hypertension, atherosclerosis, postangioplasty/in-stent restenosis, and vein graft failure. The serine/threonine protein kinase Ca2+/calmodulin-dependent protein kinase II (CaMKII) is a ubiquitous mediator of intracellular Ca2+ signals. Its multifunctional nature, structural complexity, diversity of isoforms, and splice variants all characterize this protein kinase and make study of its activity and function challenging. The kinase has unique autoregulatory mechanisms, and emerging studies suggest that it can function to integrate Ca2+ and reactive oxygen/nitrogen species signaling. Differentiated VSM expresses primarily CaMKIIγ and -δ isoforms. CaMKIIγ isoform expression correlates closely with the differentiated phenotype, and some studies link its function to regulation of contractile activity and Ca2+ homeostasis. Conversely, synthetic phenotype VSM cells primarily express CaMKIIδ and substantial evidence links it to regulation of gene transcription, proliferation, and migration of VSM in vitro, and vascular hypertrophic and hyperplastic remodeling in vivo. CaMKIIδ and -γ isoforms have opposing functions at the level of cell cycle regulation, proliferation, and VSM hyperplasia in vivo. Isoform switching following vascular injury is a key step in promoting vascular remodeling. Recent availability of genetically engineered mice with smooth muscle deletion of specific isoforms and transgenics expressing an endogenous inhibitor protein (CAMK2N) has enabled a better understanding of CaMKII function in VSM and should facilitate future studies.

Attentional bias in clinical depression and anxiety: The impact of emotional and non-emotional distracting information.

Both anxiety and major depression disorder (MDD) were reported to involve a maladaptive selective attention mechanism, associated with bias toward negative stimuli. Previous studies investigated attentional bias using distractors that required processing as part of task settings, and therefore, in our view, these distractors should be regarded as task-relevant. Here, we applied a unique task that used peripheral distractors that presented emotional and spatial information simultaneously. Notably, the emotional information was not associated in any way to the task, and thus was task-irrelevant. The spatial information, however, was task-relevant as it corresponded with task instructions. Corroborating previous findings, anxious patients showed attentional bias toward negative information. MDD patients showed no indication of this bias. Spatial information influenced all groups similarly. These results indicate that anxiety, but not MDD, is associated with an inherent negative information bias, further illustrating that the two closely related disorders are characterized by different processing patterns.

Transient, small-scale field-aligned currents in the plasma sheet boundary layer during storm time substorms.

We report on field-aligned current observations by the four Magnetospheric Multiscale (MMS) spacecraft near the plasma sheet boundary layer (PSBL) during two major substorms on 23 June 2015. Small-scale field-aligned currents were found embedded in fluctuating PSBL flux tubes near the separatrix region. We resolve, for the first time, short-lived earthward (downward) intense field-aligned current sheets with thicknesses of a few tens of kilometers, which are well below the ion scale, on flux tubes moving equatorward/earthward during outward plasma sheet expansion. They coincide with upward field-aligned electron beams with energies of a few hundred eV. These electrons are most likely due to acceleration associated with a reconnection jet or high-energy ion beam-produced disturbances. The observations highlight coupling of multiscale processes in PSBL as a consequence of magnetotail reconnection.

Using executive control training to suppress amygdala reactivity to aversive information.

The ability to regulate emotions is essential for adaptive behavior. This ability is suggested to be mediated by the connectivity between prefrontal brain regions and the amygdala. Yet, it is still unknown whether the ability to regulate emotions can be trained by using a non-emotional procedure, such as the recruitment of executive control (EC). Participants who were trained using a high-frequent executive control (EC) task (80% incongruent trials) showed reduced amygdala reactivity and behavioral interference of aversive pictures. These effects were observed only following multiple-session training and not following one training session. In addition, they were not observed for participants exposed to low-frequent EC training (20% incongruent trials). Resting-state functional connectivity analysis revealed a marginally significant interaction between training group and change in the connectivity between the amygdala and the right inferior frontal gyrus (IFG). Amygdala-IFG connectivity was significantly increased following the training only in the high-frequent EC training group. These findings are the first to show that non-emotional training can induce changes in amygdala reactivity to aversive information and alter amygdala-prefrontal connectivity.

GABA and Glutamate in Children with Primary Complex Motor Stereotypies: An 1H-MRS Study at 7T.

BACKGROUND AND PURPOSE: Complex motor stereotypies are rhythmic, repetitive, fixed, purposeful but purposeless movements that stop with distraction. They can occur in otherwise normal healthy children (primary stereotypies) as well in those with autism spectrum disorders (secondary stereotypies). The underlying neurobiologic basis for these movements is unknown but is thought to involve cortical-striatal-thalamo-cortical pathways. To further clarify potential neurochemical alterations, gamma-aminobutyric acid (GABA), glutamate, glutamine, N-acetylaspartate, and choline levels were measured in 4 frontostriatal regions by using (1)H MRS at 7T. MATERIALS AND METHODS: A total of 18 children with primary complex motor stereotypies and 24 typically developing controls, ages 5-10 years, completed MR spectroscopy at 7T. Single voxel STEAM acquisitions from the anterior cingulate cortex, premotor cortex, dorsolateral prefrontal cortex, and striatum were obtained, and metabolites were quantified with respect to Cr by using LCModel. RESULTS: The 7T scan was well tolerated by all the participants. Compared with the controls, children with complex motor stereotypies had lower levels of GABA in the anterior cingulate cortex (GABA/Cr, P = .049; GABA/Glu, P = .051) and striatum (GABA/Cr, P = .028; GABA/Glu, P = .0037) but not the dorsolateral prefrontal cortex or the premotor cortex. Glutamate, glutamine, NAA, and Cho levels did not differ between groups in any of the aforementioned regions. Within the complex motor stereotypies group, reduced GABA to Cr in the anterior cingulate cortex was significantly associated with greater severity of motor stereotypies (r = -0.59, P = .021). CONCLUSIONS: These results indicate possible GABAergic dysfunction within corticostriatal pathways in children with primary complex motor stereotypies.

Individual differences in common factors of emotional traits and executive functions predict functional connectivity of the amygdala.

Evidence suggests that individual differences in emotion control are associated with frontoparietal-limbic networks and linked to emotional traits and executive functions. In a first attempt to directly target the link between emotional traits and executive functions using resting-state fMRI analysis, 43 healthy adults completed a test battery including executive tasks and emotional trait self-assessments that were subjected to a principal component analysis. Of the three factors detected, two explained 40.4% of the variance and were further investigated. Both factors suggest a relation between emotional traits and executive functions. Specifically, the first factor consisted of measures related to inhibitory control and negative affect, and the second factor was related to reward and positive affect. To investigate whether this interplay between emotional traits and executive functions is reflected in neural connectivity, we used resting-state fMRI to explore the functional connectivity of the amygdala as a starting point, and progressed to other seed-based analyses based on the initial findings. We found that the first factor predicted the strength of connectivity between brain regions known to be involved in the cognitive control of emotion, including the amygdala and the dorsolateral prefrontal cortex, whereas the second factor predicted the strength of connectivity between brain regions known to be involved in reward and attention, including the amygdala, the caudate and the thalamus. These findings suggest that individual differences in the ability to inhibit negative affect are mediated by prefrontal-limbic pathways, while the ability to be positive and use rewarding information is mediated by a network that includes the amygdala and thalamostriatal regions.

Anti-streptococcal, tubulin, and dopamine receptor 2 antibodies in children with PANDAS and Tourette syndrome: single-point and longitudinal assessments.

Single-point-in-time ELISA optical densities for three putative antibodies identified in Sydenham's chorea, the streptococcal group A carbohydrate antigen, N-acetyl-beta-d-glucosamine, tubulin, and the dopamine 2 receptor, showed no differences in children with PANDAS (n=44) or Tourette syndrome (n=40) as compared to controls (n=24). Anti-tubulin and D2 receptor antibodies assessed in serial samples from 12 PANDAS subjects obtained prior to a documented exacerbation, during the exacerbation (with or without a temporally associated streptococcal infection), and following the exacerbation, showed no evidence of antibody levels correlating with a clinical exacerbation. These data do not support hypotheses suggesting an autoimmune hypothesis in either TS or PANDAS.

Significance of urban and agricultural land use for biocide and pesticide dynamics in surface waters.

Biocides and pesticides are designed to control the occurrence of unwanted organisms. From their point of application, these substances can be mobilized and transported to surface waters posing a threat to the aquatic environment. Historically, agricultural pesticides have received substantially more attention than biocidal compounds from urban use, despite being used in similar quantities. This study aims at improving our understanding of the influence of mixed urban and agricultural land use on the overall concentration dynamics of biocides and pesticides during rain events throughout the year. A comprehensive field study was conducted in a catchment within the Swiss plateau (25 km(2)). Four surface water sampling sites represented varying combinations of urban and agricultural sources. Additionally, the urban drainage system was studied by sampling the only wastewater treatment plant (WWTP) in the catchment, a combined sewer overflow (CSO), and a storm sewer (SS). High temporal resolution sampling was carried out during rain events from March to November 2007. The results, based on more than 600 samples analyzed for 23 substances, revealed distinct and complex concentration patterns for different compounds and sources. Five types of concentration patterns can be distinguished: a) compounds that showed elevated background concentrations throughout the year (e.g. diazinon >50 ng L(-1)), indicating a constant household source; b) compounds that showed elevated concentrations driven by rain events throughout the year (e.g. diuron 100-300 ng L(-1)), indicating a constant urban outdoor source such as facades; c) compounds with seasonal peak concentrations driven by rain events from urban and agricultural areas (e.g. mecoprop 1600 ng L(-1) and atrazine 2500 ng L(-1) respectively); d) compounds that showed unpredictably sharp peaks (e.g. atrazine 10,000 ng L(-1), diazinon 2500 ng L(-1)), which were most probably due to improper handling or even disposal of products; and finally, e) compounds that were used in high amounts but were not detected in surface waters (e.g. isothiazolinones). It can be safely concluded that in catchments of mixed land use, the contributions of biocide and pesticide inputs into surface waters from urban areas are at least as important as those from agricultural areas.

Psychotropic medication in children and adolescents in Germany: prevalence, indications, and psychopathological patterns.

OBJECTIVE: The aim of this study was to identify the "real-life" prevalence of psychotropic medications in children and adolescents in Germany and related behavioral and emotional problems. Data from the nationwide representative National German Health Interview and Examination Survey for Children and Adolescents (KiGGS) were analyzed. METHOD: A total of 17,450 subjects aged 0-17 years from 167 communities were examined as part of the KiGGS in Germany between 2003 and 2006 to determine their use of antidepressants, antipsychotics, anxiolytics, and sedatives within the 7 days prior to being interviewed. Medication use was assessed by a medical doctor who conducted a computer-assisted personal interview (CAPI) with the parents, and related emotional and behavioral problems were assessed using the Strength and Difficulties Questionnaire (SDQ). RESULTS: The overall prevalence for these medications was moderate (4.81/1000; 95% confidence interval [CI], 3.70-6.26), but prevalence varied across the different classes of drugs (sedatives > antipsychotics > antidepressants > anxiolytics). Rates of off-label use were high for antipsychotics and antidepressants. About 30% of the medication, especially sedatives, was used without prescription. Subjects using psychotropic medication obtained higher scores in the screening for emotional or behavioral problems than the total sample, but 40% of the children did not show abnormal scores. CONCLUSION: The indication for antipsychotics was mostly behavioral symptomatology, while antidepressants were used for a wide variety of symptoms. The high proportion of children and adolescents using psychotropic medication with normal scores in the emotional and behavioral screening was remarkable. It cannot be determined whether in these cases low scores were related to improvement in symptoms or whether medication was being misused.

Agent-based model for friendship in social networks.

A model is proposed to understand the structuring of social networks in a fixed setting such as, for example, inside a university. The friendship formation is based on the frequency of encounters and mutual interest. The model shows distinctive single-scale behavior and reproduces accurately the measurable experimental quantities such as clustering coefficients, degree distribution, degree correlation, and friendship distribution. The model produces self-organized community structures and can be described as a network of densely interconnected networks. For the friendships, we find that the mutual interest is the dominant factor, which optimizes the network and that the number of encounters determines the statistically relevant distributions.

Experimental observation and computer simulations of 3D triplet structures in diffusion limited growth of xenon crystals.

Changes of growth morphologies are induced by a perturbation of the thermal diffusion field in the surrounding melt of a growing xenon crystal. Apart from the dendritic morphology, seaweed and doublon morphologies and for the first time transitions from dendritic to triplet structures (first predicted by T. Abel, E. Brener, and H. Müller-Krumbhaar [Phys. Rev. E 55, 7789 (1997)10.1103/PhysRevE.55.7789] were observed experimentally. With 3D phase-field simulations it was possible to reproduce the experimental procedure and to verify that triplet structures can grow in a stable way even in the presence of anisotropic surface free energy as found for experimental substances.

Isolated left pulmonary artery: interventional stenting of a persistent fifth aortic arch.

A few cases of isolated pulmonary artery have been successfully palliated by stenting the arterial duct using coronary stents. However, progressive luminal narrowing within the stent due to neointimal proliferation and peal formation is a considerable problem. We report the successful interventional palliation in a 7-week-old infant with isolated left pulmonary artery using sirolimus-eluting stents. In this unusual case, the isolated pulmonary artery was supplied by a duct-like remnant of a persistent fifth aortic arch, whereby the distal part of this vessel showed severe constriction. Implantation of two sirolimus-eluting coronary stents re-established good perfusion of the left pulmonary artery. Seven months after the procedure, echocardiography revealed that perfusion of the stented vessel and the left pulmonary artery was still very good. Stents eluting antimitotic agents also help to preserve the patency of small vessels in infants, and may be useful for ductal stenting.

Feedback control of unstable cellular solidification fronts.

We present a feedback control scheme to stabilize unstable cellular patterns during the directional solidification of a binary alloy. The scheme is based on local heating of cell tips which protrude ahead of the mean position of all tips in the array. The feasibility of this scheme is demonstrated using phase-field simulations and, experimentally, using a real-time image processing algorithm, to track cell tips, coupled with a movable laser spot array device to heat the tips locally. We demonstrate, both numerically and experimentally, that spacings well below the threshold for a period-doubling instability can be stabilized. As predicted by the numerical calculations, cellular arrays become stable with uniform spacing through the feedback control which is maintained with minimal heating.