Growth Axis Research Articles

Impact of Electrical Current on Single GaAs Nanowire Structure

The impact of electrical current on the structure of single free‐standing Be‐doped GaAs nanowires grown on a Si 111 substrate is investigated. Single nanowires have been structurally analyzed by X‐ray nanodiffraction using synchrotron radiation before and after the application of an electrical current. The conductivity measurements on single nanowires in their as‐grown geometry have been realized via W‐probes installed inside a dual‐beam focused ion beam/scanning electron microscopy chamber. Comparing reciprocal space maps of the 111 Bragg reflection, extracted perpendicular to the nanowire growth axis before and after the conductivity measurement, the structural impact of the electrical current is evidenced, including deformation of the hexagonal nanowire cross section, tilting, and bending with respect to the substrate normal. For electrical current densities below 30 A mm−2, the induced changes in the reciprocal space maps are negligible. However, for a current density of 347 A mm−2, the diffraction pattern is completely distorted. The mean cross section of the illuminated nanowire volume is reconstructed from the reciprocal space maps before and after the application of electrical current. Interestingly, the elongation of two pairs of opposing side facets accompanied by shrinkage of the third pair of facets is found. The variations in the nanowire diameter, as well as their tilt and bending, are confirmed by scanning electron microscopy. To explain these findings, material melting due to Joule heating during voltage/current application accompanied by anisotropic deformations induced by the W‐probe is suggested.

S100P acts as a target of miR-495 in pancreatic cancer through bioinformatics analysis and experimental verification.

S100 calcium binding protein P (S100P) and miR-495 are aberrantly expressed and exert essential roles in cancers. However, the mechanisms of miR-495-S100P in pancreatic cancer are yet to be illustrated. Thus, we explored the regulatory functions of miR-495-S100P axis in pancreatic adenocarcinoma cells growth and invasion. In this study, we identified that S100P was upregulated in pancreatic adenocarcinoma by bioinformatics analysis of the GEO (Gene Expression Omnibus database) microarray dataset (GSE16515). Western blotting and luciferase reporter gene analysis exhibited that miR-495 negatively determined the level of S100P via binging to its 3'-untranslated regions (3'-UTRs). A series of functional experiments indicated that upregulation of miR-495 or S100P knockdown suppressed pancreatic adenocarcinoma cells proliferation, invasion, and promoted apoptosis. Furthermore, the expression of S100P was negatively associated with the level of miR-495 in The Cancer Genome Atlas (TCGA) pancreatic adenocarcinoma case-cohort. Besides, reintroduction of S100P debilitated the anti-cancer action of miR-495 in pancreatic adenocarcinoma cells. Our data indicated that miR-495 performed suppressive roles in pancreatic adenocarcinoma through targeting S100P.

The effect of selected in ovo green light photostimulation periods on post-hatch broiler growth and somatotropic axis activity

Targeted in ovo green light (GL) photostimulation during the last days of broiler egg incubation increases embryonic expression of the somatotropic axis, similar to in ovo green light photostimulation from embryonic day (ED) 0 to the end of incubation. The aim of this study was to examine the effect of selected in ovo GL photostimulation periods on post-hatch broiler growth. Four hundred twenty fertile broiler eggs were divided into 7 treatment groups: the first incubated in the dark (standard conditions) as a negative control; the second incubated under monochromatic GL from ED0-ED20 (positive control); the third group incubated under monochromatic GL light from ED15-ED20; the fourth, fifth and sixth groups were incubated under monochromatic GL on ED16, ED17, and ED18, respectively; and the seventh group was incubated under monochromatic GL from ED18-ED20. All illumination was provided intermittently using LED lamps. After hatch, all chicks were transferred to a controlled room under standard rearing conditions. The group incubated under green light from ED18 until hatch showed similar results to the positive control group in body weights, as well as breast muscle weights (as % of body weights), and an elevation in the somatotropic axis activity during the experiment. We suggest that broiler embryos can be exposed to in ovo GL photostimulation from ED18 until hatch (hatching period), and still exhibit the same performance as obtained by photostimulation from d 0 of incubation.

BLYSMUS COMPRESSUS (CYPERACEAE) В ВОЛОГОДСКОЙ ОБЛАСТИ

The article presents data on the distribution, biomorphology, ecological and phytocenotic features of Blysmus compressus in the Vologda Region, as well as issues of the species conservation. The choice of this species as a research object was determined by its rarity in the region and its indicator properties of the presence of pressurized groundwater outlets. Analysis of herbarium collections, archived and published data showed that from 1856 to 2020, B. compressus was recorded in 65 localities within 20 (out of 26) administrative districts and was confined mainly to the valleys of large rivers. Species records fall within the boundaries of 30 squares of the grid system adopted in the Atlas Florae Europaeae. As a result of a detailed biomorphological analysis of the species, its life form was determined as a secondary rhizome non-turfy perennial polycarpic herb with an iterative growth of the shoot axis. This type of biomorph, in its structural basis, is characteristic of the whole Cyperaceae family and the iteration seems to correspond to the ecological conditions of the ecotope. B. compressus prefers lowland (wet and often paludified) meadows, eutrophic (most often, spring) mires, banks of water bodies and watercourses. The habitats of the broad blysmus are always associated with pressurized groundwater outlets and, as a rule, rich in carbonates. B. compressus is a hemi-eurybiontic species. The species realizes its ecological potential with reasonable efficiency (Zhukova's coefficient for most of the traits was not lesser than 0.5), although, judging by the entire complex of traits, in none of the studied ecotopes is was in optimal conditions. B. compressus is listed in the Red Data Book of the Vologda Region by the 3/LC category. It was recorded within the boundaries of only four specially protected natural areas. The necessary protection measures include the organization of new nature reserves at the sites where B. compressus is found, population monitoring, and searching for new places of its occurrence.

A simple test of lichenometric dating using bidecadal growth of Rhizocarpon geographicum agg. and structure-from-motion photogrammetry

Digital photogrammetry was used to measure growth rates and track changes at the margins of marked Rhizocarpon geographicum agg. thalli on quartzite at the Illecillewaet Glacier in western Canada. The decadal rates were used to validate a lichenometric “growth curve” calibrated using the five largest thalli on historically and tree-ring dated surfaces. Macro-photographs of lichens were orthocorrected by ‘Structure from Motion’ (SfM) techniques to create a 20 yr image timeline. Model resolution was high (0.01 to 0.03 mm pix), photo alignment was accurate (mean relative error < 1.4%) and measurements were validated. Mean areal growth in 59 thalli was highly variable (x¯ = 9.43 mm2 yr−1 for 1996–2006; and 7.72 mm2 yr−1 for 2006–2016). Tiny thalli (<5 mm long axis) had jagged outlines and slow irregular growth (0 to 0.2 mm yr−1). Long axis growth in the five fastest of 45 thalli (>5 mm long axis) with circular outlines was 0.5 to 0.92 mm yr−1 and mean annual radial growth on four radii per thallus was 0.23 to 0.31 mm yr−1. Several thalli kept a nearly circular shape even after fusing with others. Extrapolated mean radial growth of the fastest thallus in either decade closely predicted the largest and five thallus sizes on historically dated surfaces (−5.43 mm difference at 53 yr, <1.75 mm at 75 to 101 yr). This is an error of about one year at 75 to 101 yr. The findings validate indirectly calibrated rates and surface ages at this site and challenge key assumptions and claims made by proponents of lichenometric dating.

Carbon and Oxygen Isotope Records of Tridacna squamosa Shells from two Different Latitudes in the Ryukyu Islands

We report carbon (δ13C) and oxygen (δ18O) isotope records of two modern giant clam (Tridacna squamosa) shells from two sites (Ishigaki-jima and Okinoerabu-jima) at different latitudes in the Ryukyu Islands, Japan. The δ13C profiles of samples from the inner shell layer on cross-sections along the maximum growth axis display no ontogenetic trends or seasonal variations. This finding suggests that the calcification site is likely to be unaffected by CO2 uptake and release resulting from the metabolic activity of the molluscan host and algal symbionts. The δ18O profiles show distinct seasonal cycles. After accounting for the influence of seawater δ18O, the time-series variations are consistent with variations in sea surface temperature, and the temperature dependency of oxygen isotope fractionation is nearly identical to previously published δ18O–temperature relationships for biogenic and synthetic aragonite. We conclude that δ18O records from pristine fossils of this species will enable accurate paleoenvironmental reconstructions at high temporal resolution.

Individual and group parameters of Rumex alpinus L. (Polygonaceae) as an indicator of the degree of disturbance to the Carpathian high-mountain meadow ecosystems

Вивчено індивідуальні (висоту генеративного пагона, довжину сегментів кореневища та їхню кількість на осі наростання) і групові параметри (проєктивне покриття, щільність імматурних особин, генеративних і вегетативних пагонів) клонального високотравного виду – Rumex alpinus у популяціях, що перебувають на різних стадіях антропогенної сукцесії в Карпатах. Цей вид здатний утворювати зімкнені рудеральні угруповання – щавельники (Rumiceta alpini) на угноєному ґрунті біля стійбищ худоби. Видові властивий тривалий онтогенез і наявність довговічних масивних кореневищ, у яких розмір сегментів відображає життєвість особини у минулі роки. Досліджені показники характеризують ступінь антропогенних змін у лучних екосистемах Карпат на різних етапах їх дигресивно-демутаційних перетворень. Значна кількість імматурних особин насіннєвого походження свідчить про молодий вік популяції і служить індикатором дигресивного спрямування змін в екосистемі. Натомість, у сформованих щільних щавельниках особини насіннєвого походження (зокрема імматурні) майже або цілком відсутні, оскільки у самовідновленні переважає вегетативне розмноження. Найвищі індивідуальні і групові параметри R. alpinus відзначено на площах, що зазнають підживлення гноївкою. Припинення господарського впливу призводить до розрідження популяцій та їх поступового згасання. В інвазійних популяціях відзначено послідовне збільшення річних приростів кореневищ, натомість у регресивних – їхнє скорочення. Rumex alpinus є також компонентом деяких корінних непорушених угруповань, де виявляє невисоку життєвість особин і низьку щільність популяцій. Отже, високі значення індивідуальних і групових показників цього виду є індикатором значного порушення території та її низької цінності з природоохоронної точки зору, натомість його нечасте трапляння лише на окремих невеликих ділянках може свідчити про відсутність або незначний ступінь девастації гірської лучної екосистеми.

Using Mg/Ca Ratios from the Limpet Patella depressa Pennant, 1777 Measured by Laser-Induced Breakdown Spectroscopy (LIBS) to Reconstruct Paleoclimate

Measurement of the elemental composition of shells is increasingly emerging as an avenue for obtaining high-resolution insights into paleoclimate and past seasonality. Several studies have shown significant correlations between Mg/Ca ratios measured on shell carbonate and the sea surface temperature (SST) within which this carbonate was precipitated. However, other investigations have reported large variability in this relationship between species. Therefore, further studies, including taxa previously not considered are still required in order to validate these new species as suitable climate proxies. Here, we measured Mg/Ca ratios for limpet Patella depressa Pennant, 1777 samples live-collected in northern Spain for the first time. The elemental ratio was measured using laser-induced breakdown spectroscopy (LIBS), a technique that significantly decreases the time required for sample preparation and increases the number of shells that can be analyzed. In this study, calibration-free LIBS (CF-LIBS) methods were applied to estimate molar concentrations of chemical elements on biogenic calcium carbonate. The Mg/Ca ratio evolution along the shell growth axis was compared with stable oxygen isotope (δ18O) profiles obtained from these same limpets and the SST at the place where the mollusk grew to determine if the sequences obtained correctly reflected environmental conditions during the life-span of the mollusk. The results showed a significant correlation between Mg/Ca ratio series and both δ18O profiles and SST, highlighting the paleoenvironmental and archaeological potential of LIBS analyses on this mollusk species that is frequently found in archaeological contexts in the western Europe.

The NIMH Intramural Longitudinal Study of the Endocrine and Neurobiological Events Accompanying Puberty: Protocol and rationale for methods and measures

Delineating the relationship between human neurodevelopment and the maturation of the hypothalamic-pituitary-gonadal (HPG) axis during puberty is critical for investigating the increase in vulnerability to neuropsychiatric disorders that is well documented during this period. Preclinical research demonstrates a clear association between gonadal production of sex steroids and neurodevelopment; however, identifying similar associations in humans has been complicated by confounding variables (such as age) and the coactivation of two additional endocrine systems (the adrenal androgenic system and the somatotropic growth axis) and requires further elucidation. In this paper, we present the design of, and preliminary observations from, the ongoing NIMH Intramural Longitudinal Study of the Endocrine and Neurobiological Events Accompanying Puberty. The aim of this study is to directly examine how the increase in sex steroid hormone production following activation of the HPG-axis (i.e., gonadarche) impacts neurodevelopment, and, additionally, to determine how gonadal development and maturation is associated with longitudinal changes in brain structure and function in boys and girls. To disentangle the effects of sex steroids from those of age and other endocrine events on brain development, our study design includes 1) selection criteria that establish a well-characterized baseline cohort of healthy 8-year-old children prior to the onset of puberty (e.g., prior to puberty-related sex steroid hormone production); 2) temporally dense longitudinal, repeated-measures sampling of typically developing children at 8-10 month intervals over a 10-year period between the ages of eight and 18; 3) contemporaneous collection of endocrine and other measures of gonadal, adrenal, and growth axis function at each timepoint; and 4) collection of multimodal neuroimaging measures at these same timepoints, including brain structure (gray and white matter volume, cortical thickness and area, white matter integrity, myelination) and function (reward processing, emotional processing, inhibition/impulsivity, working memory, resting-state network connectivity, regional cerebral blood flow). This report of our ongoing longitudinal study 1) provides a comprehensive review of the endocrine events of puberty; 2) details our overall study design; 3) presents our selection criteria for study entry (e.g., well-characterized prepubertal baseline) along with the endocrinological considerations and guiding principles that underlie these criteria; 4) describes our longitudinal outcome measures and how they specifically relate to investigating the effects of gonadal development on brain development; and 5) documents patterns of fMRI activation and resting-state networks from an early, representative subsample of our cohort of prepubertal 8-year-old children.

Magnetic field dependence of the in-plane hole g factor in ZnSe- and CdTe-based quantum wells

The effective $g$ factor of holes is measured in modulation-doped ZnSe/(Zn,Mg)(S,Se) quantum wells and from surface-state $p$-doped CdTe/(Cd,Mg)Te quantum wells by time-resolved pump-probe Kerr rotation. The measurements are performed at a temperature of 1.7 K and in magnetic fields up to 5 T applied in the Voigt geometry with orientation perpendicular to the quantum-well growth axis. The absolute value of the in-plane hole $g$ factor increases with growing magnetic field in both studied heterostructures. A theoretical model is developed that considers the influence of magnetic field and interface mixing of heavy-hole and light-hole states on the $g$ factor. The model results are in good agreement with the experimental data.

A crosstalk between auxin and brassinosteroid regulates leaf shape by modulating growth anisotropy

Leaf shape is highly variable within and among plant species, ranging from slender to oval shaped. This is largely determined by the proximodistal axis of growth. However, little is known about how proximal–distal growth is controlled to determine leaf shape. Here, we show that Arabidopsis leaf and sepal proximodistal growth is tuned by two phytohormones. Two class A AUXIN RESPONSE FACTORs (ARFs), ARF6 and ARF8, activate the transcription of DWARF4, which encodes a key brassinosteroid (BR) biosynthetic enzyme. At the cellular level, the phytohormones promote more directional cell expansion along the proximodistal axis, as well as final cell sizes. BRs promote the demethyl-esterification of cell wall pectins, leading to isotropic in-plane cell wall loosening. Notably, numerical simulation showed that isotropic cell wall loosening could lead to directional cell and organ growth along the proximodistal axis. Taken together, we show that auxin acts through biosynthesis of BRs to determine cell wall mechanics and directional cell growth to generate leaves of variable roundness.

Fe2O3 hierarchical tubular structure decorated with cobalt phosphide (CoP) nanoparticles for efficient photoelectrochemical water splitting

• Fabrication of large surface area and high crystallinity CoP/SnO 2 :Fe 2 O 3 HTS for PEC application. • The role of SnO 2 and CoP on the oxidation reaction kinetics in the photoanode system was proved. • The highest photocurrent density of 3.54 mA cm −2 at 1.23 V RHE among the Fe 2 O 3 -based photoanodes. Severe charge recombination and poor water oxidation kinetics limit the performance of hematite-based (Fe 2 O 3 ) photoanodes far from their theoretical levels and restrict their applicability for photoelectrochemical (PEC) water splitting devices. In this study, a hierarchical tubular structure (HTS) CoP/SnO 2 :Fe 2 O 3 with a large surface area and well-defined crystalline structures was fabricated via a facile template-engaged redox etching method. The SnO 2 nano-layer served as a dopant source to improve the bulk charge carrier transport efficiency along the Fe 2 O 3 HTS growth axis; therefore, the achieved photocurrent could be up to 2.0 mA cm −2 at 1.23 V RHE (V vs. reversible hydrogen electrode). The CoP nanoparticles (NPs) were introduced as a high-speed hole collector from the light-absorber layer as well as a catalyst to enhance charge carrier injection efficiency on the photoelectrode surface. As a result, CoP/SnO 2 :Fe 2 O 3 shows the highest photocurrent density of 3.50 mA cm −2 (at 1.23 V RHE ) with a negative shift in the onset potential of 180 mV.

Increase in the radiative decay rate of the indirect exciton due to application of the magnetic field

The indirect excitons in double quantum well structures can appear in the ground state under application of an external electric field along the growth axis. The relatively slow radiative decay rate of the indirect exciton can be enhanced by a magnetic field pointing in the same direction. In this report, we numerically calculate the exciton energy levels in the GaAs-based double quantum well structure as well as optimize parameters of the structure to allow a noticeable increase in the radiative decay rate of the indirect exciton there by application of the magnetic field.

Synergy and orientation of "tourist wtp - wta community" in the dimension of conservation economic growth of tourist destination resources

The concept of ecotourism is a form of management of tourist destinations that prioritizes the preservation of tourism resources, both physical and social culture of the local community. Conservation-oriented activities will guarantee an optimal life cycle and utilization time than oriented towards economic growth. Government and businessmen are the components that play a direct role in controlling the orientation and suitability of the Tourism Willingness to Pay (WTP) with the community’s Willingness to Accept (WTA). The analytical instruments models to synergize and orient travelers WTPs and WTA communities, with the support of government and business actors. This instrument includes the acquisition of data on tourists, the local community, the government and businessmen. The data is formulated in the form of WTP and WTA vectors in the conservation-economic growth coordinate system. The activity orientation tendency is determined by the angle between the WTP and WTA vectors against abscissa (conservation axis) and ordinate (axis of economic growth). Input WTP and WTA vector data into the life cycle of a tourist destination will determine the time to achieve optimal utilization of destination resources. This instrument was developed for the analysis and control of the management of tourist destinations. It can be adapted for the management of other resources that confront the interests of certain parties (such as entrepreneurs) with the local community.

Reconstructing Seasonal and Baseline Nitrogen Isotope Ratios in Riverine Particulate Matter Using Freshwater Mussel Shells

AbstractWe present a timeline of the carbon, nitrogen, and oxygen stable isotope compositions of 10 unionid mussel shells across three species–Threeridge (Amblema plicata), Ebonyshell (Reginaia ebenus), and Pimpleback (Cyclonaias pustulosa)—collected live in 2011 from the Tennessee River near Paducah, Kentucky, USA. Inorganic aragonite δ18O profiles were compared to a predicted shell δ18O time series that was based on water temperature and isotopic composition. Shell growth was assumed to stop below ∼12°C. Profiles of inorganic δ18O and δ13C were then used to establish relationships between shell growth and calendar dates. Because shell growth is faster during warmer months and therefore easy to sample, assignment of calendar years to individual growth increments was validated using the interannual changes in the predicted minimum δ18O value of summer shell. Mussel shell periostracum and carbonate‐bound organic matter (CBOM) samples were then assigned calendar dates based on their location along shell growth axes and compared to measurements of δ13C and δ15N of suspended particulate organic matter (SPOM)–the mussels' food source–during shell growth (1997–2006). Mussel shell periostracum and CBOM faithfully recorded seasonal variability in δ15N and δ13C values of SPOM, after accounting for the time difference between SPOM consumption and deposition of shell organics due to the gradual turnover of mantle tissue. This demonstrates that unionid shell geochemistry could be used to document changes in riverine environment, runoff, and nutrient cycles across a spectrum of time scales, from historical to archeological to Quaternary.

Porites Calcifying Fluid pH on Seasonal to Diurnal Scales

AbstractCoral resilience to ocean acidification is largely determined by the degree of physiological control corals can exert on their calcifying fluid carbonate chemistry. In this study, the boron isotopic composition (δ11B) of a Porites colony growing on a reef flat on Kiritimati Island in the equatorial central Pacific is examined to quantify the sensitivity of calcifying fluid pH (pHcf) to ambient environmental conditions. Skeletal δ11B along the growth axis of one annual growth band was determined with bulk analysis and by laser ablation (LA) MC‐ICP‐MS. Furthermore, the oxygen and carbon isotopic composition, trace element ratios, and skeletal density were quantified. Sclerochronological data were interpreted in the context of simultaneous recordings of reef flat seawater pH (pHsw), temperature, salinity, and water depth, and by measurements of these parameters on the fore‐reef. A recent model of pHcf upregulation, after optimization with seasonally resolved data, was used to simulate pHcf variability on a diurnal scale. Results showed that on a seasonal scale, Porites pHcf is upregulated compared to ambient seawater: both bulk and LA‐MC‐ICP‐MS derived δ11B resulted in a mean pHcf of 8.35 pH units. Calcifying fluid pH upregulation primarily followed variations in seawater temperatures, that is likely related to the control of temperature on calcification rate. On the reef flat, the diurnal range in pHsw was substantially higher (0.29 pH units) than on the fore‐reef (0.07 pH units). However, model results suggest that the high diurnal variability in reef flat pHsw resulted only in a limited variability in Porites pHcf.

YAG:Yb crystal with non-linear doping ions distribution as promising active element for high average power laser systems

The influence of optical centers concentration profiles on thermal fields under high-power end-face diode pumping is analyzed using numerical model. It is shown that non-uniform distribution profiles of optical centers concentration are very promising for high average pump power laser amplifiers. The possibility of creating concentration profiles of optical centers in gradient-activated crystals with YAG matrix with a specified distribution along the growth axis of the crystal is demonstrated. A technology of growing gradient-activated single crystal involving active mirror as active element is proposed and discussed.

Effects of Circular RNA of Chicken Growth Hormone Receptor Gene on Cell Proliferation.

Animal growth and development are regulated by neural and endocrine growth axes, in which cell proliferation plays key roles. Recently, many research showed that circular RNAs were involved in hepatocyte and myoblast proliferation. Previously, we identified a circular RNA derived from the chicken GHR gene, named circGHR. However, the function of circGHR is unclear. The objective of this study was to investigate circGHR expression pattern and its roles in cell proliferation. Results indicated that circGHR was a closed-loop structure molecule, and it was richer in the nucleus of hepatocytes and myoblast. Real-time PCR showed that circGHR was increased from E13 to the 7th week in the liver but decreased in the thigh and breast muscle. The CCK-8 assay displayed that circGHR promoted cell proliferation. Simultaneously, the biomarker genes PCNA, CCND1, and CDK2 and the linear transcripts GHR and GHBP were upregulated when circGHR was overexpressed. Altogether, these data exhibited that circGHR could promote cell proliferation possibly by regulating GHR mRNA and GHBP expression.

Hormone seasonality in medical records suggests circannual endocrine circuits

Hormones control the major biological functions of stress response, growth, metabolism, and reproduction. In animals, these hormones show pronounced seasonality, with different set-points for different seasons. In humans, the seasonality of these hormones remains unclear, due to a lack of datasets large enough to discern common patterns and cover all hormones. Here, we analyze an Israeli health record on 46 million person-years, including millions of hormone blood tests. We find clear seasonal patterns: The effector hormones peak in winter-spring, whereas most of their upstream regulating pituitary hormones peak only months later, in summer. This delay of months is unexpected because known delays in the hormone circuits last hours. We explain the precise delays and amplitudes by proposing and testing a mechanism for the circannual clock: The gland masses grow with a timescale of months due to trophic effects of the hormones, generating a feedback circuit with a natural frequency of about a year that can entrain to the seasons. Thus, humans may show coordinated seasonal set-points with a winter-spring peak in the growth, stress, metabolism, and reproduction axes.

Potential Mechanisms of miR-143/Krupple Like Factor 5 Axis in Impeding the Proliferation of Michigan Cancer Foundation-7 Breast Cancer Cell Line

Breast cancer is one of the most prevailing cancers in females, while the cancerous heterogeneity hinders its early diagnosis and subsequent therapy. miR-143-3p is a critical mediator in malignancy development and tumorigenesis as a tumor suppressor. Its role in various tumor entities has been investigated, such as colon cancer and breast cancer. Using MCF-7 breast cancer cell model, we planned to explore the underlying mechanisms of miR-143/KLF-5 axis in retarding breast cancer cells growth. Bioinformatics analysis searched the target KLF5 of miR-143, and the miR-143-targeted mimic and inhibitor were employed to detect the changes of KLF5. After transfection of mimic miR-143, the CCK-8 reagent assessed cell proliferation. Based on optimal stimulation time, miR-143 stimulation model was established, followed by determining expression of KLF5, EGFR and PCNA via western blot and qPCR. Eventually, siRNA-KLF5 was applied to silencing KLF5 level to evaluate its role in MCF-7 cells. The transcription and translation levels of KLF5 were diminished in miR-143-mimic transfected MCF-7 cells, while enhanced in miR-143-inhibitor transfected MCF-7 cells. When MCF-7 cells were transfected with miR-143-mimic at different time points, 48 hours was found to be the optimal transfection time, with reduced transcription and translation levels of KLF5, EGFR and PCNA. The transcription and translation levels of PNCA and EGFR were declined after silencing KLF5 by siRNA. miR-143/KLF5 axis could retard the proliferation of MCF-7 breast cancer cells.