Performance of Raspberry-Like Gold Nanoparticles (Au RLNPs)

Performance of Raspberry-Like Gold Nanoparticles (Au RLNPs) Improvement of Stability and Catalytic Performance of Raspberry-Like Gold Nanoparticles by Silica Coating High Catalytic Performance of Raspberry-Like Gold Nanoparticles (Au RLNPs) and Enhancement of Stability by Silica Coating Kiouk Seo, Hien Mai Duy and Hyojong Yoo* Abstract. The raspberry-like gold nanoparticles (Au RLNPs) synthesized through the reduction of HAuCl4 by the use of NaOH and Brij35 surfactant show high catalytic activities in the reduction of 4-nitrophenol and ethanol electrooxidation. The enhanced catalytic activities of Au RLNPs are mainly due to their high surface area. However, Au RLNPs easily change to the spherical or aggregated nanoparticles in a treatment with acids, thiols, and cationic surfactants (ex, CTAB)), and are difficult to sustain the catalytic activities. To improve the stability and applicability, Au RLNPs core–silica shell nanoparticles (Au [emailprotected]2 NPs) were successfully synthesized in solution without losing their original morphologies through a simple solution-phase sol-gel process with the assistance of surface-stabilizing polymeric agent (Polyvinylpyrrolidone (PVP)). In comparison with Au RLNPs and other Au nanoparticles, Au [emailprotected]2 NPs could be more easily recovered and recycled in the repeated catalytic reactions. Keywords Raspberry-like gold nanoparticles (Au RLNPs), Silica coating, Catalytic reduction, Ethanol electrooxidation, Polyvinylpyrrolidone (PVP) 1. INTRODUCTION Noble metals have gained much attention over the past two decades due to their potentials in a wide variety of applications including energy conversion[1][2], chemical and biological sensing[3], and bioengineering[4]. Tremendous research efforts have been devoted towards the exploration of how to design nanomaterials with varied topographies that has led to the discovery of their fundamental size-, shape-, and component-dependent properties and the development of new applications[5][6][7]. Moreover, it has theoretically and experimentally found that arrays of asymmetric surface features, particularly deviations from spherical geometry, mainly impart unique anisotropy in material properties7. Apparently, to achieve such desired anisotropic topographies strict control is required. Conversely, this leads to a generation of particles with novel properties from the same materials by simply tuning the particle morphology. Furthermore, anisotropic geometry offers numerous unique features an d functionalities that are either difficult to obtain or even hardly obtained by simple size-tuning in spherical counterparts. Morphology of nanoparticles also strongly affects the catalytic performance. This is due to the surface anisotropy possessing a high density of low-coordinated atoms such as steps, edges, and defects serving as catalytically active sites which can markedly affect chemical and physical properties of nanoparticles[8]. Among those colloidal gold (Au) nanoparticles exhibit not only highly tunable architecture-dependent optical properties but also show excellent performance and high selectivity in a variety of heterogeneous green catalytic processes [ref][9][10]. For a better stability, catalytic performance, and reusability of Au nanoparticles, engineering new nanocatalyst system is thus considered one of the most critical tasks. Recently, in our group, we successfully synthesized raspberry-like gold nanoparticles (Au RLNPs) with rich edges and high surface areas through the reduction of HAuCl4 by Brij35 surfactant under basic condition in a controllable fashion [ref]. The synthesized Au RLNPs possess high surface areas and show the unique, highly-red shifted surface plasmon resonances (SPRs) due to the rough, raspberry-like surface of Au RLNPs. These structures also have high surface energies due to their plenty of tips and edges. These nanoparticles are stable and retain their raspberry-like geome try in basic or neutral conditions; however gradually reshape to the spherical geometry under a specific circumstance such as acidic condition. In order to exploit the unique shape-dependent properties of the Au RLNPs in a variety of catalytic applications, further modifications of nanoparticles such as endowing core-shell structure are thus required. Metallic nanostrutures of several different shapes have been coated with silica since the silica shells used as the coating material show substantial enhancement in the stability of the metal cores, particularly in aqueous solvents. Moreover, metallic nanostructured surface can readily functionalized by subsequently coating with silica and using silane-coupling reactions [ref]. Additionally, silica shells are chemically inert, transparent in the visible and IR regions of the spectrum, and readily converted to mesoporous layer [11]. For the direct encapsulation of Au nanoparticles within silica shells, the conventional techniques is employing coupling agents with silane group for the growth of silica shells on the surfaces of as-synthesized Au nanoparticles via the Stà ¶ber method [ref]. However, we experimentally found that directly applying this method to coat Au RLNPs brought challenges since the unusual size changes of Au RLNPs without disturbing the rough surface occurred. Herein, we report the synthesis of Au [emailprotected]2 NPs in solution through a simple solution-phase sol-gel process. To protect the high-energy surface of Au RLNPs, Polyvinylpyrrolidone (PVP) was used prior to the condensation of TEOS as a polymeric stabilizer. Au [emailprotected]2 NPs showed great enhancement in stability under the strongly acidic condition. The catalytic performance, recovery, and reusability of both Au [emailprotected]2 NPs and Au RLNPs were investigated using the reduction reaction of 4-nitrophenol (4-NP) as a reaction model. We also found that and Au RLNPs were capable of electrocatalyzing alcohol oxidation reactions in alkaline media. 2. EXPERIMENTAL DETAILS 2.1. Reagents Polyoxyethylene glycol dodecyl ether ((C2H4O)23C12H25OH, Brij35, Acros Organics), hydrogen tetrachloroauratetrihydrate (HAuCl4†¢3H2O, 99.9%, Sigma–Aldrich), polyvinylpyrolidone ((C6H9NO)n, PVP10, average mol wt 10,000, Sigma–Aldrich), 4-nitrophenol (O2NC6H4OH, 99%, Sigma–Aldrich), sodium hydroxide (NaOH, 97%, Sigma–Aldrich), ammonium hydroxide (NH4OH, 28-30 wt % ammonia, Sigma–Aldrich), tetraethyl orthosilicate (Si(OC2H5)4 98%, Sigma–Aldrich), hexadecyltrimethylammonium bromide ((C16H33)N(CH3)3Br, 99%, Acros Organics), (3-mercaptopropyl)methyldimethoxysilane (CH3Si(OCH3)2CH2CH2CH2SH, 95%, Alfa Aesor), HCl, HNO3, and ethyl alcohol were used as received. All stock solutions were freshly prepared before each reaction. Prior to use, all glassware was washed with Aqua Regia (volume ration of 3:1 of concentrated HCl and HNO3; Caution: Aqua Regia is highly toxic and corrosive and must be handled in fume hoods with proper personal protection equ ipment) and rinsed thoroughly with deionized water. 2.2. Synthesis of raspberry-like gold nanoparticles (Au RLNPs) Au RLNPs with the mean size of approximately 60-70 nm were prepared according to our previous literature [ref]. Briefly, an aqueous Brij35 solution (1 mL; 19.3 wt%) was well mixed with NaOH (aq) (100  µL; 100mM) by shaking for 30 seconds. To this mixture, HAuCl4 (aq) (50  µL; 10 mM) was added, and shaken vigorously for 1 minute. The pale yellow reaction mixture then turned to blue within 5 minutes at room temperature. To make sure a complete reaction, this mixture was allowed to react for over 20 minutes before being collected by centrifugation (5 min; 13500 rpm), and redispersed in deionized water. 2.3. Synthesis of Au RLNPs@SiO2 NPs The preparation of Au [emailprotected]2 NPs was as follows: firstly, the as-synthesized Au RLNPs were dispersed in 1 mL of deionized water. Next, 0.235 mL polyvinylpyrrolidone (PVP10) aqueous solution (128 mg of PVP10 in 10 mL of deionized water) was added to the Au RLNPs solution. The resulting mixture was then stirred at room temperature for 12 hours to ensure complete adsorption of PVP on Au RLNPs. Afterward, the PVP-capped RLNPs were purified by centrifugation (5 min; 13500 rpm), and redispersed in solvent mixture containing 1 mL deionized water and 7 mL ethyl alcohol. In the next step, tetraethylorthosilicate (TEOS, 0.03 mL) and ammonium hydroxide (0.2 mL of 14.8 M NH4OH (aq.)) were sequentially added to the PVP-capped Au RLNPs aqueous solution and the reaction mixture was further stirred at room temperature for 4 h. After the completion of the reaction, the resultant Au [emailprotected]2 NPs were centrifuged, and purified by repeatedly washing in ethanol and centrifugation. 2.4. Catalytic reduction of 4-nitrophenol The catalytic reduction of 4-nitrophenol (4-NP) over nanoparticles in the presence of NaBH4 was carried out to assess the catalytic activity. In a typical experiment, 2 mL of deionized water, 1.7 mL of 0.2 mM 4-NP, and 1 mL of 15 mM NaBH4 solutions were mixed in a quartz cuvette followed by the addition of 1 mL of Au [emailprotected]2 NPs solution. The color of solution changed gradually from yellowish to clear as the reaction proceeded. UV-Vis spectra were recorded at a 5-minute intervals to monitor the progress of the reaction. 2.5. Ethanol electrocatalytic oxidation All electrochemical measurements were carried out in a conventional three-electrode cell at ambient temperature (~25ËÅ ¡C) using WPG 100e Potentiostat (WonAtech Inc.). The fabrication of working electrode is as follow: Prior to electrochemical experiments, glassy carbon (GC) electrode was sonicated in ethanol and deionized water successively. 10  µL of RLNP suspension was dropped onto carbon disk and the solution is dried at room temperature. Platinum and Ag/AgCl were employed as counter and reference electrodes, respectively. With an aqueous mixture of 0.5 M KOH and 1.0 M ethanol as electrolytes, at least 10 cycles of cyclic voltammetry were carried out before recyclable voltammograms were recorded. Throughout the cyclic voltammetry experiments, the potential window was between -0.2 V and 0.8 V. Prior to experiments, the electrolytes were degased by bubbling with nitrogen for 30 min. 2.6. Characterization The nanoparticles were imaged using a Hitachi S-4800 scanning electron microscope (SEM), and a JEOL JEM-2010 Luminography (Fuji FDL-5000) Ultramicrotome (CRX) transmission electron microscope (TEM). Samples were prepared for TEM by concentrating the nanoparticle mixture by centrifuging twice for 5 min at 13500 rpm with resuspension in 100 ÃŽ ¼L nanopure water and immobilizing 10 ÃŽ ¼L portions of the solution on Formvar-coated Cu grids. Extinction spectra were recorded with a UV-vis spectra spectrometer (UVIKON XS). Solution pH was measured using an Orion 420 A+ pH meter. 3. RESULTS AND DISCUSSION Initially, the highly monodisperse Au RLNPs with controlled diameters ranging from 60 to 70 nm (Fig. 1a and S1) [Images and size distribution of RLNP] were prepared according to protocols developed previously.ref Polyvinylpyrrolidone (PVP) was then employed as a primer and a direct growth of silica onto the PVP-capped Au RLNPs to obtain Au [emailprotected]2 NPs was carried out using solution-phase sol-gel method with TEOS as a precursor. PVP, which have been often used as a surface-stabilizing polymeric agent to prepare spherical Au core – SiO2 shell nanoparticles,ref was used to protect the high-energy surface of Au RLNPs. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of Au [emailprotected]2 NPs (Fig. 1b-d) show the well-established core-shell structure in which the as-synthesized Au RLNPs were uniformly and individually encompassed within silica shells whereas still sustaining their rough and edge-rich surfaces advantageous to catal ytic performance. The average diameter of individual Au [emailprotected]2 NPs was xxxxx (xxx particles was evaluated, Fig 1e). With respect to RLNPs cores, the average size was nearly similar to that of RLNPs before silica-coated (Fig S1). The UV-Vis spectra plotted in Fig. 1f, a noticeable broadeness in the corresponding surface plasmon bands in Au [emailprotected]2 NPs compared to that of Au RLNP were observed. It is well know that the weaker and broader surface plasmons are observed,, due to the change of refractive index of surrounding environment after silica coating step[b1].ref [Fig 1] High catalytic efficiency of Au nanocatalysts were mainly due to their high roughness and plethora of edge-rich surfaces and corners.ref Thus it necessitates assessing whether catalytically active surfaces of the synthesized nanoparticles are stable in various environments. HCl, CTAB, and MPTS were introduced into the colloidal solution of the as-synthesized RLNPs in order to understand the stability of Au RLNPs in different ambiences. Fig. 2 shows typical SEM images displaying changes in geometries of Au RLNPs as adding diverse reagents. It is experimentally observed that Au RLNPs collectively changed to spherical nanoparticles with the smooth surface as adding HCl (Fig S2)ref corresponding to a blue-shift in UV-Vis spectrum toward approx. 520 nm which can be assigned to the surface plasmon resonance (SPR) of gold nanospheres. This phenomenon could be attributed to the oxidative etching effect which has been employed to control the size of other noble nanostructures in recent papers [12] [13] [14]. Meanwhile, as shown in Fig. 2a, much agglomeration occurred as adding CTAB. However, it is interesting to note that the aggregation also occurred without disturbing their raspberry-like motifs, as adding MPTS (Fig. 2b). The SPR changes shown in UV-Vis spectra (Fig. 2e) further confirmed this aggregation. The introduction of such reagents, which might affect the hydrodynamic layer thickness of Au RLNPs, accounts for this unusual alteration in particles size. The [emailprotected]2 NPs however exhibited no geometrical change when HCl was added. As shown in Fig. 3a, SEM images show that the [emailprotected]2 NPs still retained their original raspberry-like morphology without any observable agglomeration. This observation is also consistent with results obtained from UV-Vis spectra (Fig. 3b) that there was no detectable shift in SPR peak of the core-shell nanoparticles after HCl had been added. Ethanol comprises a lower toxicity, a higher theoretical energy density (8.01 kW.h kg-1) than methanol (6.09 kW.h kg-1) and formic acid (1.74 kW.h kg-1), and fewest environmental issues[15] [16]. Moreover, ethanol is a renewable source that can be easily produced massively from the chemical industry or fermentation of biomass. In this study, electrooxidation of ethanol [HM2]in KOH solution was performed to probe relative electrocatalytic activities of the synthesized nanoparticles. Fig. 4 shows the cyclic voltammograms of RLNPs, HCl-etched RLNPs[HM3], and [emailprotected]2 NPs for ethanol electrooxidation. It is clear that the RLNPs exhibit almost substantially higher electrocatalytic performance with a forward oxidation current (iF) value of 0.56 mA compared to that for HCl-etched RLNPs (iF, 0.07 mA). The high electrocatalytic activity of the RLNPs is attributed to the existence of high energetic surfaces in raspberry-like morphologies. However, [emailprotected]2 NPs did not show an y electrocatalytic activities over the entire potential window. This is explained that silica shells hindered the electron transfer between gold cores and electrode due to silica shells are insulating. The catalytic reduction of 4-NP to their corresponding derivatives, 4-aminophenol, in the presence of NaBH4 was chosen as a model reaction in order to evaluate the catalytic activity of Au [emailprotected]2 NPs. It is well established that the reduction of 4-NP by NaBH4 is thermodynamically feasible but kinetically restricted without a catalyst. The reduction progress was monitored by UV-Vis absorption spectra after the addition of catalysts. The characteristic absorption peak of 4-NP aqueous solution was located at 400 nm after NaBH4 had been added. First of all, in the absence of catalysts the reduction reaction of 4-NP did not proceed even with a large excess of NaBH4. However, when catalysts were introduced, the reduction of 4-NP was clearly observed. The absorbance of the reaction mixture at 400 nm gradually decreased as the reaction proceeded, along with the concomitant increase of 300 nm peak, corresponding to 4-aminophenol. Fig. 4 illustrates the UV-Vis spectra changes of 4-N P as a function of reaction time in the presence of Au RLNPs (Fig. 4a) and Au [emailprotected]2 NPs (Fig. 4c). Fig. 4e shows the change in concentration of 4-NP was plotted versus time, providing a general view to compare catalytic activities of Au RLNPs and Au [emailprotected] ­2 NPs (Ct: absorbance of 4-NP at specific reaction time, t; C0: initial absorbance of 4-NP as catalysis starts). The Ct/C0 is measured from the relative intensity of absorbance (At/A0). As can be seen, Au RLNPs exhibited comparatively higher catalytic activity than their core-shell counterparts, possibly owning to silica shell hindering the diffusion of reactants onto inner gold active sites. Interestingly, in the presence of HCl, the catalytic activity of Au [emailprotected]2 NPs however was not only improved, but also dramatically higher than that of Au RLNPs which was suffering from the morphological change, leading to severe degradation of active sites (Fig. 4e). In addition, we also investigated the d egree of reusability of the two catalysts. As shown in Fig. 5, the catalytic efficiencies of Au RLNPs decreased remarkably after reused 3 times whilst Au [emailprotected]2 still retained good catalytic performance for as far as 7 cycles. It is apparent that the stability and reusability of Au RLNPs were improved significantly after encapsulated into silica shell, resulting in maintenance in their catalytic activity. 4. CONCLUSIONS Acknowledgments: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2011-0008968). This research was also supported by Hallym University Research Fund 2012 (HRF-G-2012-3) References and Notes 1 [1] Linic, S.; Christopher, P.; Ingram, D. B. Nat. Mater. 2011, 10, 911. [2] Jiang, R.; Li, B.; Fang, C.; Wang, J. Adv. Mater. 2014, DOI: 10.1002/adma.201400203. [3] Zhang, Y.; Guo, Y.; Xianyu, Y.; Chen, W.; Zhao, Y.; Jiang, X. Adv. Mater. 2013, 15, 3802. [4] Tokel, O.; Inci, F.; Demirci, U. Chem. Rev. 2014, 114, 5728. [5] Tawfick, S.; Volder, M. D.; Copic, D.; Park, S. J.; Oliver, R.; Polsen, E. S.; Roberts, M. J.; Hart, A. J. Adv. Mater. 2012, 24, 1628. [6] Jones, M. R.; Osberg, K. D.; Macfarlane, R. J.; Langille, M. R.; Mirkin, C. A. Chem. Rev. 2011, 111, 3736. [7] Sau, T. K.; Rogach, A. L. Adv. Mater. 2010, 22, 1781. [8] Quan, Z.; Wang, Y.; Fang, J. Acc. Chem. Res. 2013, 46, 191. [9] Zhang, Y.; Xiao, Q.; Bao Y.; Zhang, Y.; Bottle, S.; Sarina, S.; Zhaorigetu, B.; Zhu, H. J. Phys. Chem. C 2014, 118, 19062. [10] Liu, X.; He, L.; Liu, Y.-M.; Cao, Y. Acc. Chem. Res. 2014, 47, 793. [11] Park, J.; Yoo, H. Microporous Mesoporous Mater. 2014, 185, 107. [12] Li, B.; Long, R., Zhong, X.; Bai, Y; Zhu, Z.; Zhang, X.; Zhi, M.; He, J.; Wang, C.; Li, Z.-Y.; Xiong, Y. Small 2012, 8, 1710. [13] Liu, M.; Zheng, Y.; Zhang, L.; Guo, L.; Xia, Y. J. Am. Chem. Soc. 2013, 135, 11752. [14] Chiu, C.-Y.; Yang, M.-Y.; Lin, F.-C.; Huang, J.-S.; Huang, M. H. Nanoscale 2014, 6, 7656. [15] Hong, W.; Wang, J.; Wang, E. ACS Appl. Mater. Interfaces 2014, 6, 9481. [16] Antolini, E.; Gonzalez, E. R. J. Power Sources 2010, 195, 3431. [b1]When gold NPs’ re encapsulated within silica, there’s generally red-shift in the absorbant peak of SPR. Please check this data once again. [HM2]In Fig. 4, I think it better to insert the 2 images of RLNP and Hcl-etched RLNPs to say that the latter surface is not as edge-rich as the former. [HM3]Considering how to name RLNPs whose morphology was change to sphere as adding HCl

Early Language and Development Essay

Language is a complex and abstract endeavor, wonderfully creative at the same time governed by a multitude of rules. Before the age of 1 year, babies communicate with intent, primarily through the use of body orientation, facial expressions, gestures, and nonsymbolic vocalizations that mimic the intonations of their native language. At the end of the first year, however, many babies are beginning to use word approximations, consistent combinations of sounds as a transition to language, a symbolic system of communication. During the toddler years, language development is focused on semantics, or the meaning of words, and on syntax the rules of grammar for the language. (Slentz, et al. , 2001) Early language developments are crucial stage to one’s life. Baby’s language are through actions, and it could mean various meaning. Babies can’t speak yet, but they have their own ways to let us know how they feel. From the beginning, a mother and baby can be seen attuning to each other. They copy each other’s movements and expressions with mutual relaxed smiles, and later with laughing delight. (Clulow, et al. , 1993) Attunement is an essential factor for speech and language in general. According to John Bowlby (1980) early month – infant bonding and attachment are crucial to early language and development, thus it should be given importance by the mother to her baby as soon the baby was born. It is also noted that our feelings are easier to convey or communicated with infants. For an instance, baby cries when he hears another baby crying or when a mother the mother is angry while holding the baby, the baby becomes fussy. (Klein, 1987) Moreover, at an early stage, the mother’s speech affirms and responds to the infant’s eagerness to become involved in â€Å"proto-conversation†, a non – verbal form of discourse. Speech engages attention, communicates feelings, and facilitates social interaction as well as facilitating language acquisition. (Clulow, et al. , 1993) If a mother cannot attune to her baby’s rhythm then, as a result the baby will become distressed. This in turn stresses his mother, usually upsetting more, so that a vicious circle is likely. From birth onwards, children can be regarded as active participants in interaction. As for intentionality, young children develop along a continuum, in which they gradually learn to use more sophisticated and conventional means to communicate and also demonstrate increasing competence in intentionally conveying meanings to their interactive partners. The most common communicative functions of early intentional communicative acts have been found to be requests for objects/actions and comments on objects/actions (Paavola et al. ,2005) A mother’s ability to monitor her child’s visual attention and exhibition of a vocal or an exploratory act and then to respond promptly, contingently and appropriately is usually referred to as responsiveness. There is a lot of evidence for the supporting role of maternal responsiveness in child language development However; the efficacy of maternal responsiveness may not be global. Instead, it has been suggested that certain aspects of responsiveness are more predictive than others to particular language outcomes in the child. Furthermore, it is possible that children differ in their needs to be guided and supported by their mothers, which leads to differences in maternal role in early interactions (Paavola et al. , 2005) According to Harris (1992) the relationship between the cognitive/perceptual processes involved in development and the child’s linguistic experiences. The first steps in language development and the role of adult-child interaction (both verbal and nonverbal) are very important. The focus is on the way parents–mothers in particular–structure the child’s language-learning experiences so that they are conducive to the steps the child must take to master the first stages of language acquisition. Moreover, Harris (1992) concludes that early lexical development (the learning of an initial vocabulary) may be more sensitive to individual differences in parental interaction styles than has been demonstrated to be the case for syntactic development. Hence, the emphasis of the monograph is on the period and processes of parent interaction and child language development from the pre-verbal phases, from 6 month of age, through to the appearance of word combinations, around 2 years of age; that is, roughly Brown’s (1973) Stage I and early Stage 2. There are 3 major theoretical controversies about the nature and process of language development; the research into the influence of adult speech on children’s learning language; the role of the social interactional context in assisting language development; the child’s use of the immediate referential context in progressing through the first steps in language development; and what constitutes appropriate evidence with which to address these issues. (Harris, 1992) In the early weeks of life, pragmatic skills (responding to verbal and non-verbal aspects of language) develop as babies interact with their carers through crying, blinking and smiling. First words appear between 12 and 18 months. (http://www. literacytrust. org. uk/Research/earlylanguage. html) ? 12-month-olds can distinguish between words, mouth sounds and object noises. They have linguistically specific knowledge of the privileged status of language. (Pruden, et al. , (2006) ? Children aged 18 to 35 months demonstrate learning through integration of earlier instruction with subsequent problem-solving experience. Toddlers are not passive learners. (Chen and Siegler, 2000) Furthermore, according to the website http://www. literacytrust. org. uk, Mother-child dynamic in language learning has been central to early year’s research. Mothers are often the predominant influences in children’s early years. The concentration on maternal speech input implies that mothers share a unique relationship with their children as they learn language, that mothers are programmed to respond to children’s sounds in a way that reinforces early language development and, in turn, that the child has an innate capacity for learning language. Early studies in this area found that mother’s speech facilitates, and, in some cases, hinders the language development of young children. Social contact between parents and infants are considered to be a contributing factor in language development. It is also noted that social interaction with other people can either impede or development the babies language. Environment and culture can influence one’s speech as well. A baby whose parents are Asian and American and living in Europe could somehow impede his speech especially when there are different languages at home. Being specific at an early age could help the baby understand more and becomes attuned to his surroundings. Additionally, when the child verbally establishes complex connections and relations between perceived phenomena with the help of an adult, the child introduces at each moment essential qualitative changes in the receptivity and interpretation of sensory input to his brain. When a child acquires a word which isolates a particular thing and serves as a signal for a particular action, the child carries out an adult’s verbal instruction is connected to this word. (Eveloff, 1971) Toddlers build vocabulary based on unique experiences, and new words are acquired at an average rate of one word per week until children are 18 months old. Some toddlers focus on primary words that refer to objects and people, and developing strategies such as asking â€Å"what’s that† to elicit noun labels in response from adults. Other youngsters had vocabularies with more words for affect, motion or location, expressive language. Language is considered to be the most significant adaptive measure available to developing human. Language is highly related to developmental hierarchies such as neurophysiologic, cognitive, and affective. .(Slentz, et al. , 2001) Overall, early language and development starts with parents or the babies caregiver, it is an essential factor for parents to be educated properly on what are their roles in developing their babies language. Babies’ language development can impede or progress, depending on the ability of the parents and how they interact with their babies. I personally believe that education is the best tool in order to achieve great results for communicating well. Language, speech, and emotions can be linked together. Emotions are greatly expressed through words, and thus this will lead to how we can influence the child’s language and development. Parents are foremost educators on developing the characteristic and personality of the child. Language factor is another contributing aspect on how the child will become in the future. References: Bowlby, J. (1980) Loss: Sadness & Depression [Vol. 3 of Attachment and Loss]. London: Hogarth Press; New York: Basic Books; Harmondsworth: Penguin (1981). Brown, R. W. (1973) A First Language: the Early Stages. Cambridge, Harvard University Press Chen, Z. , & Siegler, R. S. (2000). Across the great divide: bridging the gap between understanding of toddlers’ and older children’s thinking. Monographs of the Society for Research in Child Development 65 No. 2 Clulow, C. (1993) Human Development: An Introduction to the Psychodynamics of Growth, Maturity and Ageing. Psychology Press UK Eveloff, H (1971) Some Cognitive and Affective Aspects of Early Language Development Child Development, Dec71, Vol. 42 Issue 6, p1895-1907, 13p; Harris, M (1992) Language Experience and Early Language Development: from input to Uptake Hove, UK: Lawrence Erlbaum Associates Paavola, et al. , (2005) Maternal responsiveness and infant intentional communication: implications for the early communicative and linguistic development.. Child: Care, Health & Development, Nov2005, Vol. 31 Issue 6, p727-735, 9p; Pruden, et al. , (2006) The Birth of Words: Ten-Month-Olds Learn Words Through Perceptual Salience Child Development 77 (2), 266–280. Slentz, K. , & Krogh (2001) Early Childhood Development and Its Variations. Mahwah, N. J. Lawrence Erlbaum Associates, Inc. â€Å"Early language development: a review of the evidence for birth to age three† can be accessed at http://www. literacytrust. org. uk/Research/earlylanguage. html (accessed February 22, 2007)

Inspiration for Inquiry Essay

The school that is subject for evaluation in this paper is a charter school in Michigan, a publicly funded school, which means, the students are not allowed to pay any charges beyond the funds allocated to the school.   The state and the local district is the one that provides for the operation.   Since the school is instituted to meet the greater demand for education, this school is non-sectarian and non-discriminatory. It accepts all types of students regardless of religion or race.   In the same way, religious or cultural beliefs are not prohibited here.   The obvious problem in this school is that, students are selected by lottery to avoid any biases in the assortment since the school cannot accommodate students beyond their limit.   The school is serving an economically disadvantaged and racially diverse population.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Being a relatively small public school, this school receives monetary support and services from both the state and local government lower than conventional public schools.   As a result of conducted test, assessment of students’ outcomes is generally low.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The staff of the school particularly the principal is less experienced and has less management credentials.   Teachers here on the other hand, are very efficient for they have active participation especially in informal professional development such as mentoring and shadowing.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   However, despite good performances, the school experience insufficiencies especially if we will consider its long-term success. Although the school has given autonomy yet, it is bounded in such a way that parents have direct involvement in them.   Likewise, teachers are found less motivated after three years of teaching for seeing that school mission is not met by the school. Teaching staff comprises about fifty percent of the total staff, about forty percent of these teachers are in twenties, while the females are in seventy percent.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Teachers are notably satisfied with the school facilities but not in their salaries. Aside from that, only few teachers are enrolled in the retirement program of the state.   Their expectations before they were hired were higher than what they experience.   The reason according to authorities, the school receive minimal budget from the local government.   In effect, most of these teachers after gaining enough experience would move to other school.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Teachers are highly receptive for change, and that is why they expect for change from both the board of directors and the parents.   At least sufficient intervention from the local government and parents are needed to mend these needs.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   In view of organizational climate, parents participate less in the direction of the school.   The less experienced principal cannot do something about the problem.   The teachers behave in such a way that maintains what actually exists with mind to get out once the needed employment experience has been satisfied.   They all work for the accomplishment of set goals without great desire for a much higher academic achievements. Teachers are performing quite well for a limited sources and privileges that affect generally the instruction.   People are seemingly individualistic aiming to sustain the daily challenges having no definite direction ahead of them since no regular monitoring for corrective measures are prearranged.   Likewise, students are less challenged and grades are relatively low. Inquiry Statement   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The problems manifested in this paper require a considerable attention from proper authorities particularly the principal.   Specific issues that sought deliberation are formulated for key areas of concern. How could the school generate enough funding for their annual expenditures? Funding is seen as the number one problem; this is the reason why the school cannot create programs for the development of the curriculum and facilities that hinders cooperative values among them. How the school could produce technical supports needed to meet academic requirement? Other concerns that may not be covered by the budget can be produced through technical supports.   If needs are met, the culture of cooperation among the staff can be developed. What are the necessary steps to improve the quality of instruction in the classroom? It aims to improve not only the quality of education but also the credibility of the teachers.   The value of competitiveness must be developed among the teachers and staff. What necessary steps are needed to promote professional growth of the teachers? Professional growth of teachers is significant to maintain teachers’ retention.   This can be achieved by giving trainings to teachers and by upgrading their salaries.   This will help develop commitment among the teachers. What standardized evaluation is to formulate to measure the school performance? Regular evaluation of teachers’ performance, students’ scholastic achievement, and school performance as well, will ensure growth of the school.   Once the school has clearly established goals, teachers would be challenged to participate in the achievement of goals. What policies are to integrate that will develop in-depth structure of parents-teachers organization.   This aims to promote good partnership between parents and school for the improvement of the school. These inquiry statements are formulated in order to guide the leader in creating a culture that meets organizational objectives. Hypothesis               . The question that needs to be asked to determine whether our school faculty is receptive of change is whether they are willing to move their institution towards greater focus on student learning and success. I believe that in order for the institution to achieve its goal, the school system not only the faculty should promote a community environment that is receptive to change. Indeed the need for change in the operation of college and universities is becoming obvious. Change is now the much-loved term of organizational development.   Everyone must be willing to alter change that starts from the upper level of the organization.   However, if no one would be willing to open their eyes for greater impact in the community, no change will occur. In the same way, once the needs for improvement have been identified, a structured-plan must be implemented in such a way that results are interrelated that affects the organization as a whole. In effect, a different organizational culture will be formed.   These are the desirable values and norms that support one another toward the growth of each one; of course for the achievement of mission and vision of the school.   This time, the value of time, cooperation, participation, respect, commitment, and camaraderie begin to envelope the organization. Evidence from the Literature In the foreword of Christine Johnson’s McPhail (2005) book, she pointed out that,   Ã¢â‚¬Å"Projection done by the Bureau of Labor Statistic show a growing disparity between job requirements and employee skills. Higher education institution, including community colleges, needs to accept more responsibility for what our students learn† (p. vi).   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Johnson asserts that most schools and community colleges are changing their instructional program and services, recruitment, hiring, training of faculty, and service delivery, almost daily. Johnson emphasized the reason behind these changes is to recapture the drive that founded the schools and community college movement, reinforced its multiple missions, and to find expression in the success of the learner. Thus in our school system, the need for change of our faculty has been recognized as an important catalyst of improving the institution towards the student greater learning and expression of success. Our faculty is receptive of this change in view of the need to address the growing disparity between job requirements and employee skills.   Marvin Wideen and Ivy Pye (1994) noted that teachers’ first concern about change in the institution is all about â€Å"teaching and learning activities† for improvement of student learning (p. 135). As the need for change is recognized as important in the development of the professional learning communities a leader therefore should build culture that will support the professional learning communities in practice by establishing a culture of intellectual discipline distinct from the professional standard of the institution. Armstrong, Thompson, and Brown (1997) emphasized that academic managers has the critical role to â€Å"encourage and support colleagues’ adaptation to change† (p. 98).   Some of the values that must be developed is intellectual discipline, which means an emphasis on professionalism in thinking, speaking, and in doing, in other words, making it a habit to be professional. Another way to build a culture that will support professional learning communities in practice is to develop a culture of caring and obliging community. In contrast with individualism and consumerism, this will help professionals to be more at ease and cheerful as they perform their work. It is quite a familiar idea that its not at all monetary issue that is important in the work place. Creating such cultures can establish positive values and attitudes that are important towards sustaining interpersonal relationship. Richard Barrett (2006) noted that harmonious interpersonal relationships is significant for the survival of the organization; hence, there should be â€Å"a sense of loyalty and belongingness among employees and a sense of caring and connection between the organization and its customers† (p. 29). In the same manner, cultural values in an organization play an important role in directing change.   Weiner and Ronch (2003) emphasized that â€Å"culture is constructed of values, beliefs, and assumptions about how the world works; values represent the organization’s ideas about what ought to be (p. 16).   He further stated that values rooted in the culture provide the foundation and guiding elements in the organization that drive people to follow. Findings   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   In what ways, school culture can influence leadership?   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Preeddy and Glatter stated, â€Å"Culture is the glue that holds everyone together† (p. 96).   Normally, cultural values influence leadership.   It is explained using a double-headed arrow.   The school leader is part of the school that influences it. Being a part of that culture, the leader uses leadership that caters to the need and values of the people.   In the same way, the kind of leadership affects or influences the culture of the organization.   It is a give and take response because a culture gradually changes as many people come in and participate.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Cultural values are possible using the idea that school culture can affect leadership.   Leadership must direct cultural change, and the kind of leadership that can move the culture to undergo change is penetrating the culture itself and identify weaker areas that need change.   Once the need is recognized, the group can be motivated to alter change for the better.   The school above is open for change if only the leader is open to initiate such change. Work Cited Armstrong, S., Thompson, G., & Brown, S. 1997. Facing Up to Radical Changes in Universities and Colleges.   UK: Routledge. Barrett, Richard. 2006. Building a Values-Driven Organization: A Whole System Approach to Cultural Transformation. UK: Elsevier Inc. McPhail, Christine. 2005. Establishing & Sustaining Learning-Centered Community Colleges.   USA: American Association of Community Colleges. Preedy, M. & Glatter, R. 2003. Strategic Leadership and Educational Improvement. London: Sage Publication Company. Weiner, A. & Ronch, J. 2003. Culture Change in Long-Term Care. USA: Haworth Press. Wideen, M. & Pye, I. 1994. The Struggle for Change: The Story of One School.   UK: Routledge.

Bon vs Bien - Mauvais vs Mal

The French words bon and bien, mauvais and mal are often mixed up. This is because the two pairs have similar meanings: bon and bien are positive while mauvais and mal are negative. In addition all four of these words can be adjectives, adverbs, or nouns. Bon and mauvais are usually adjectives, while  bien and mal are usually adverbs. The following table summarizes the differences between each pair; click the links below for more information. adjective good well bad wrong adverb nice well bad badly noun form good(s) bad part evil