Slow Expansion Research Articles

A preliminary 3-D comparison of rapid and slow maxillary expansion in children: A randomized clinical trial.

This study compared the effects of rapid maxillary expansion (RME) and slow maxillary expansion (SME) using cone-beam computed tomography (CBCT). To evaluate the skeletal and dentoalveolar effects produced by two different maxillary expansion protocols. Eligibility criteria included maxillary transverse deficiencies in children (mean age, 8.18years old), randomly assigned to either RME or SME. At the outcome analysis phase, a sample of 29 subjects were analysed (RME group, N=16 and SME group, N=13). CBCT scans taken before expansion and 6months later were evaluated. Five posterior and 6 anterior transverse measurements were made at different vertical levels. Treatment changes were analysed using paired t tests; independent t tests were used to compare the two groups. There were statistically significant (P<.05) increases in maxillary width at the skeletal, alveolar, and dental levels for both groups, with significantly smaller increases at the more superior than inferior levels. The RME group exhibited statistically larger width increases than the SME group for all measures except interorbital width, anterior alveolar process width, and intercanine width. The group differences were greater for anterior than posterior apical base widths. Rapid maxillary expansion produced greater orthopaedic effects than slow maxillary expansion, with the greatest effects occurring in the anterior apical base.

Longitudinal Stability of Rapid and Slow Maxillary Expansion: A Systematic Review

To review the long-term stability of slow maxillary expansion (SME) and rapid maxillary expansion (RME). A systematic review of literature was carried out on the principal medical databases. Cephalometric studies, measurements on the dental casts, retrospective, cohort studies were kept as inclusion criteria. Last 20 years articles were included in the study. The studies where expansion had been performed by any one of the methods of expansion; that is, SME and RME were accepted. Studies where posttreatment follow-up had been performed were included. Selected articles were independently evaluated by three researchers. Discrepancies were resolved by discussion to reach a common consensus. Total of 151 articles were first shown as relevant articles but after sorting the article according to relevancy in a stepwise manner 12 articles fulfilled the inclusion criteria and were incorporated in the study finally. In the study, nine prospective and three retrospective studies which had followed patients after maxillary expansion from 2 to 15 years were included. Correction with slow and rapid palatal expansion appears to be stable in the long-term when followed for extended periods after expansion treatment. The article clearly describes the effectiveness of the expansion treatment and its longitudinal stability in terms of relapse by providing various evidences from the literature which were sought after systematically searching the different electronic databases.

Unidirectional growth of organic single crystals of naphthalene, anthracene and pyrene by isothermal expansion of supercritical CO2.

Unidirectional single crystals without grain boundaries are highly important in optoelectronic applications. Conventional methods to obtain such crystals involve organic solvents or seed crystals, which have numerous drawbacks. We present here a supercritical CO2-mediated method of the single crystal formation of naphthalene, anthracene and pyrene on the (001) plane without using seed crystals. Single dominant peaks in powder XRD (PXRD) with low full width at half maxima (FWHM) are described. The dependency of crystal size on the rate of depressurization was measured by precise and isothermal expansion of scCO2 solutions. The experimental setup is illustrated for continuous preparation without emission of CO2 or discharge of material into the environment. The materials are shown to be fully converted into crystals indicating a rapid, scalable and environmentally benign process of single crystal formation with practically nil E factor.

The Economic Value of Carbon Sequestration through Tree Planting in Laos

Because tree plantations in Laos show that, despite high profitability, tree farmers and private companies face many challenges, including low timber quality, low timber prices, and slow plantation expansion, the aim of this study is to evaluate the social costs and benefits from private tree plantations by considering both market and non-market values, specifically for carbon sequestration. A policy decision tool - specifically cost-benefit analysis ? was employed. Existing data from Laos and other locations were used to investigate the economic and social aspects of government policy implications for forest plantation for eucalyptus and teak. A dual-discounting approach was applied to discount future net benefits of market and non-market components to arrive at a present value. We found the monetary benefit of carbon sequestration of teak and eucalyptus tree plantations to be $472.8 million (2020 dollars) over 30 years. It is concluded that the government should intervene by improving systems and regulations that can increase the private rate of return and eventually incentivize the private sector to plant more trees.

Testing massive star evolution, star-formation history, and feedback at low metallicity

Context.The supergiant ionized shell SMC-SGS 1 (DEM 167), which is located in the outer Wing of the Small Magellanic Cloud (SMC), resembles structures that originate from an energetic star-formation event and later stimulate star formation as they expand into the ambient medium. However, stellar populations within and surrounding SMC-SGS 1 tell a different story.Aims.We present a photometric study of the stellar population encompassed by SMC-SGS 1 in order to trace the history of such a large structure and its potential influence on star formation within the low-density, low-metallicity environment of the SMC.Methods.For a stellar population that is physically associated with SMC-SGS 1, we combined near-ultraviolet (NUV) photometry from the Galaxy Evolution Explorer with archival optical (V-band) photometry from the ESO Danish 1.54 m Telescope. Given their colors and luminosities, we estimated stellar ages and masses by matching observed photometry to theoretical stellar isochrone models.Results.We find that the investigated region supports an active, extended star-formation event spanning ∼25−40 Myr ago, as well as continued star formation into the present. Using a standard initial mass function, we infer a lower bound on the stellar mass from this period of ∼3 × 104 M⊙, corresponding to a star-formation intensity of ∼6 × 10−3 M⊙kpc−2yr−1.Conclusions.The spatial and temporal distributions of young stars encompassed by SMC-SGS 1 imply a slow, consistent progression of star formation over millions of years. Ongoing star formation, both along the edge and interior to SMC-SGS 1, suggests a combined stimulated and stochastic mode of star formation within the SMC Wing. We note that a slow expansion of the shell within this low-density environment may preserve molecular clouds within the volume of the shell, leaving them to form stars even after nearby stellar feedback expels local gas and dust.

The maxillary expansion procedures, the types, and the root resorption analysis methods

Transversal constriction of the maxilla is a common problem and may occur due to many reasons.The maxillary expansion procedures can be classified as rapid maxillary expansion (RME), semi-rapid maxillary expansion (SRME), and slow maxillary expansion (SME). In orthodontic treatment prosodure, it has been evaluated that it causes root resorption especially in the support teeth in many apparatus used for orthodontic treatment and in the expansion apparatus used in the treatment of transverse direction of maxilla. In this review, we aimed to evaluate maxiller expansion protocols and the methods of examining resorption in support teeth.&#x0D; &#x0D; How to cite this article: Topal R, Gündüz Arslan S. The maxillary expansion procedures, the types, and the root resorption analysis methods. Int Dent Res 2019;9(3):145-51.&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Сравнительный анализ методик расширения верхней челюсти с использованием ортодонтических аппаратов

Palatal dilation techniques were developed as a method of applying significant force to the upper jaw in a horizontal plane to rupture the median palatal suture. To achieve this goal, various designs of devices have been developed over the years. The subject of the study of many authors were changes in the bone and dental system, as well as the duration of treatment results obtained due to the use of functional devices with different rates of action. The rate of expansion depends on the level of applied forces and the mode of activation of the device. There are 3 rates of expansion of the upper jaw: slow, semi-rapid and rapid. An alternative to rapid palatal expansion with the activation of the screw 1-2 times a day is a slow expansion with the activation of the screw 1 every 2 days or using of another type of apparatus, where the source of activation is the spring. The study, which compared the device with a spring and the device for rapid palatal expansion of adolescents, showed that they have a similar effect. The available data indicate that histological examination of sutures after palatal dilation confirmed the presence of pronounced activity of both apposition and resorption [25,26]. Devices for rapid palatal expansion (RPE/RME-rapid palatal/maxillary expansion), as well as semi-rapid and slow expansion are traditionally used as a method of correction of cross bite. In addition, they are used to increase the perimeter of the dentition of the upper jaw, normalize the level of the Wilson curve, expand the smile and to increase the patency of the respiratory tract. Maxillofacial anatomy is a critical factor influencing the pathophysiology of obstructive sleep apnea. In combination with decreased oral volume, transverse maxillary deficiency is known to be a key contributor to obstructive sleep apnoe. After GNE, there is an increase in the volume of the nasal cavity and a decrease in the resistance of the nasal airflow. RME also allows the tongue to protrude forward and upward, expanding the space of the posterior pharyngeal airway during sleep [31, 32]. With regard to the pathology of the bite, the cross bite is much more common because of the narrow upper jaw than because of the insufficient width of the lower jaw. The most popular way to treat this pathology is rapid expansion of the jaw (RME).

Policies for managing peak stock of food grains for effective distribution: A case of the Indian food program

The Indian food program has encountered a significant shortfall in storage due to slow expansion of storage facilities in comparison with procurement. The open storage of food grains results in substantial loss and deterioration of quality. While increasing storage capacity is a viable but costly and time consuming option, the adoption of policies for peak storage reduction would go a long way towards effective food grains management. On this background, this study proposes policy adoption for peak storage reduction for effective inventory management. A dynamic simulation model was built by replicating the complex flow process and incorporating the process variability for finding the bottleneck and significant factors. It was found that steep wheat procurement is the critical bottleneck factor for peak storage requirements. Two practical and straightforward, yet effective policies are proposed from the few existing strategies for peak storage reduction owing to the constraints associated with the food program. With the actual data of the food program, reduction in peak stock was estimated for the recommended policies, including the operational cost saving in storage. The practical implications of these policies within the system were also discussed. Through peak reduction, the use of open storage can be significantly reduced, and this leads to better food grains management for effective food distribution.

A Novel Katanin-Tethering Machinery Accelerates Cytokinesis.

Cytokinesis is fundamental for cell proliferation [1, 2]. In plants, a bipolar short-microtubule array forms the phragmoplast, which mediates vesicle transport to the midzone and guides the formation of cell walls that separate the mother cell into two daughter cells [2]. The phragmoplast centrifugally expands toward the cell cortex to guide cell-plate formation at the cortical division site [3, 4]. Several proteins in the phragmoplast midzone facilitate the anti-parallel bundling of microtubules and vesicle accumulation [5]. However, the mechanisms by which short microtubules are maintained during phragmoplast development, in particular, the behavior of microtubules at the distal zone of phragmoplasts, are poorly understood. Here, we show that a plant-specific protein, CORTICAL MICROTUBULE DISORDERING 4 (CORD4), tethers the conserved microtubule-severing protein katanin to facilitate formation ofthe short-microtubule array in phragmoplasts. CORD4 was specifically expressed during mitosis and localized to preprophase bands and phragmoplast microtubules. Custom-made two-photon spinning disk confocal microscopy revealed that CORD4 rapidly localized to microtubules in the distal phragmoplast zone during phragmoplast assembly at late anaphase and persisted throughout phragmoplast expansion. Loss of CORD4 caused abnormally long and oblique phragmoplast microtubules and slow expansion of phragmoplasts. The p60 katanin subunit, KTN1, localized to the distal phragmoplast zone in a CORD4-dependent manner. These results suggest that CORD4 tethers KTN1 at phragmoplasts to modulate microtubule length, thereby accelerating phragmoplast growth. This reveals the presence of a distinct machinery to accelerate cytokinesis by regulating the action of katanin.

Quantifying Spatiotemporal Patterns and Major Explanatory Factors of Urban Expansion in Miami Metropolitan Area During 1992–2016

Urban expansion is one of the most dramatic forms of land transformation in the world and it is one of the greatest challenges in achieving sustainable development in the 21st century. Previous studies analyzed urbanization patterns in areas with rapid urban expansion while urban areas with low to moderate expansion have been overlooked, especially in developed countries. In this study, we examined the spatiotemporal dynamics of urban expansion patterns in South Florida, United States (US) over the last 25 years (1992–2016) using Remote Sensing and GIS techniques. The main goal of this paper was to investigate the degree and spatiotemporal patterns of urban expansion at different administrative level in the study area and how spatiotemporal variance in different explanatory factors influence urban expansion in this region. More specifically, this research quantifies the rates, types, intensity, and landscape metrics of urban expansion in Miami-Fort Lauderdale-Palm Beach, Florida Metropolitan Statistical Area (Miami MSA) which is the 7th largest MSA and 4th largest urbanized area in the US using remote sensing (satellite imageries) data from National Land Cover Datasets (NLCD) and Coastal Change Analysis Program (C-CAP) at 30 m spatial resolution. We further investigated the urban growth patterns at the county and city areas that are located within this MSA to portray the local ‘picture’ of urban growth in this region. Urban expansion in this region can be divided into two time periods: pre-2001 and post-2001 where the former experienced rapid urban expansion and the later had comparatively slow urban expansion. Results suggest that infilling was the dominant type of urban expansion followed by edge-expansion and outlying. Results from landscape metrics represent that newly developed urban lands became more aggregated and simplified in form as the time progressed in the study region. Also, new urban lands were generated away from the east coast and historic cities which eventually created new urban cores. We also used correlation analysis and multiple linear stepwise regression to address major explanatory factors of spatiotemporal change in urban expansion during the study period. Although the influence of factors on urban expansion varied temporally, Population and Distance to Coast were the strongest variables followed by Distance to Roads and Median Income that influence overall urban expansion in the study area.

Comparing the effects of fast and slow expansion on nasal cavity and maxilla structure

This study aims to compare the effects of fast and slow expansion on nasal cavity structure. A total of 40 patients were selected and randomly divided into two groups. Cone-beam computer tomography (CBCT) was obtained before and after surgery and used for comparing the changes in nasal structure before and after treatment. Fast expansion had resulted in greater changes in the basilar and nasal bone arch extension structures than slow expansion. No significant difference at maxillary width and nasal parenchyma. Rapid expansion therapy has more beneficial effects on nasal function.

“Swimming Jellyfish“: Visualizing Jet-Like Internal Flow in Coalescing Droplets

Abstract Surface-tension-driven droplet coalescence has received significant attention due to its significant role in microfluidics, coalescence-induced droplet jumping, fluid mixing, and microscale heat and mass transfer. However, the study of internal flow characteristics of merging droplets remains a challenge due to visualization difficulty, limited droplet size control, poor droplet manipulation, and insufficient droplet front tracking. Here, in order to study droplet coalescence dynamics, a droplet dispensing and visualization system was developed. To control the size of droplets, monodispersed droplets with diameters of ≈ 40 μm were dispensed onto a superhydrophobic surface, enabling the target droplets to accumulate in volume and grow in radii. To track the internal flow front, an ethanol (20 wt %)-water mixture was used as the working fluid. Due to the unequal evaporation rate of water and ethanol, a density gradient was introduced at the liquid-gas interface of the droplets, resulting in a lower refractive index compared to that in the bulk liquid. The coalescence process of droplets with diameters of ≈ 232 μm and ≈ 1400 μm was imaged. We observed jet-like internal flow and vortex rings (“swimming jellyfish”) inside the merging droplet. It was shown that the jet-like flow underwent a significant deceleration while the vortex-ring experienced slow radial expansion. Our work not only presents a powerful platform capable of visualizing droplet coalescence hydrodynamics, but also provides insights into the internal flow dynamics during droplet coalescence.

Cathelicidin Peptides Restrict Bacterial Growth via Membrane Perturbation and Induction of Reactive Oxygen Species.

All metazoans produce antimicrobial peptides (AMPs) that have both broad antimicrobial and immunomodulatory activity. Cathelicidins are AMPs that preferentially kill Gram-negative bacteria in vitro, purportedly by assembling into higher-order structures that perforate the membrane. We utilized high-resolution, single-cell fluorescence microscopy to examine their mechanism of action in real time. Engineered cathelicidins rapidly bound to Gram-negative and Gram-positive cells and penetrated the cytoplasmic membrane. Rapid failure of the peptidoglycan superstructure in regions of active turnover caused leakage of cytoplasmic contents and the formation of membrane-bound blebs. A mutation anticipated to destabilize interactions between cathelicidin subunits had no effect on bactericidal activity, suggesting that cathelicidins have activities beyond perforating the membrane. Nanomolar concentrations of cathelicidins, although not bactericidal, reduced the growth rate of Gram-negative and Gram-positive bacteria. The cells exhibited expression changes in multiple essential processes, including protein synthesis, peptidoglycan biosynthesis, respiration, and the detoxification of reactive oxygen species (ROS). Time-lapse imaging revealed that ROS accumulation preceded bleb formation, and treatments that reduced cellular ROS levels overcame these bactericidal effects. We propose that that the primary effect of cathelicidins is to induce the production of ROS that damage bacterial molecules, leading to slowed growth or cell death. Given their low circulating levels in vivo, AMPs may serve to slow bacterial population expansion so that cellular immunity systems can respond to and battle the infection.IMPORTANCE Antimicrobial peptides (AMPs) are an important part of the mammalian innate immune system in the battle against microbial infection. How AMPs function to control bacteria is not clear, as nearly all activity studies use nonphysiological levels of AMPs. We monitored peptide action in live bacterial cells over short time frames with single-cell resolution and found that the primary effect of cathelicidin peptides is to increase the production of oxidative molecules that cause cellular damage in Gram-positive and Gram-negative bacteria.

Island biogeography in continental areas: inferring dispersal based on distributional patterns of Pronophilina butterflies (Nymphalidae: Satyrinae) in the north Andean massifs

Faunal structure, species relationships and distribution patterns of Pronophilina butterflies, a Neotropical montane section of the Satyrinae (Nymphalidae), of 5 isolated north Andean massifs —Cordillera de Merida, Sierra El Tama, Sierra Nevada de Santa Marta, Cordillera de la Costa and Sierra de Perija— are analyzed from the island biogeography perspective. El Tama range, a part of the “continental” Eastern Cordillera, is considered as the source area of the faunas of the Sierra de Perija and the Cordillera de Merida, which in turn are stepping stones for the dispersal of species to the Sierra Nevada de Santa Marta and the Cordillera de La Costa. The role of major biogeographical variables is evaluated in the process of colonization of these areas. It is conlcuded that the maximum elevation between the neighbouring ranges is the most important variable, not the distance. This is related to the fact that dispersal in this group of butterflies seems to occur by slow expansion through ecological corridors not by long distance flights. Faunal relationships between the 5 ranges and the elevational bands occupied by widespread and endemic species allow inferring the extent of vertical movements of cloud forests in the past.

Sustainability and the Built Environment: The Role of Durability

A sustainable city combines stable long-term economic growth with a resilient ecological system. It is also a region of social sustainability with low levels of spatial segregation of different socio-economic groups. Spatial inclusion primarily involves provision of equalized city-wide access to territorial public goods. High durability of physical networks and buildings facilitates economic, environmental and social sustainability. This study shows that durability varies considerably between Asian, European and North American cities, with mean life expectancies of buildings that range from below 20 years in Chinese cities to over 100 years in European cities such as Paris. Urban planning principles that focus on the slow and steady expansion of accessibility and density within a durable built environment are consistent with general economic equilibria, while avoiding the pitfalls of political planning of the markets for private goods.

Molecular characterization and evolutionary dynamics of measles virus sequences isolated from children in Lagos and Ibadan, South Western, Nigeria

Measles infection is endemic in Nigeria, with outbreaks occurring yearly. Genotype B3 is the dominant genotype and the only genotype characterized from Nigeria. The current study investigated the phylogenetic and Bayesian evolutionary dynamics of Nigerian measles virus Nucleoprotein (N) sequences isolated from Lagos and Ibadan, Nigeria. A total of 120 throat swab samples were analysed by RT-PCR and Sanger sequencing. Phylogenetic analysis and Bayesian demographic reconstructions were done using MEGA and BEAST software. Measles RNA positivity was 14.2% (17/120), age range 0–1 recorded the highest rate with 40.83%. Study sequences clustered within clade B3.1. The evolutionary rate of analysed B3 sequences was 1.108×10−3, higher posterior density HPD interval (1.462×10−3 – 7.886×10−4)subs/site/year. The time to most recent common ancestor (TMRC), was 1991. The Bayesian skyride analysis(BSP) of West African MV cladeB3.1, showed a stable, steady state population demography. This study has reemphasised the dominance of clade B3.1 in Nigeria. We have shown that clade B3.1 was recently introduced into circulation and has a slow population expansion. We advocate for the institution of molecular surveillance country wide in order to help monitor strain diversity and genetic evolution of Measles in Nigeria.

Slow expansion in the scalar-tensor theory of gravity

In this paper, we analyze the slow expansion scenario in the scalar-tensor theory of gravity. After considering the slow expansion solution H≃0, we discuss the slow expansion in the scalar-tensor theory by terms of the nearly scale-invariant primordial power spectrum and find that the primordial power spectrum can be determined by the coupling function f(φ). After the slow expansion phase ends, general relativity can be recovered under certain conditions, and then the universe evolves in accordance with the standard cosmology. In the scalar-tensor theory, the slow expansion scenario provides a possible way to avoid the big bang singularity.

Minimal mortality and rapid recovery of the dominant shrub Larrea tridentata following an extreme cold event in the northern Chihuahuan Desert

AbstractQuestionsWoody encroachment into grasslands is a worldwide phenomenon partially influenced by climate change, including extreme weather events. Larrea tridentata is a common shrub throughout the warm deserts of North America that has encroached into grasslands over the past 150 years. Physiological measurements suggest that the northern distribution of L. tridentata is limited by cold temperatures; thus extreme winter events may slow or reverse shrub expansion. We tested this limitation by measuring the response of individual L. tridentata shrubs to an extreme winter cold (−31°C) event to assess shrub mortality and rate of recovery of surviving shrubs.LocationSevilleta National Wildlife Refuge, Socorro County, New Mexico, USA.MethodsCanopy dieback and recovery following an extreme cold event were measured for 869 permanently marked individual L. tridentata shrubs in grass–shrub ecotone and shrubland sites. Individual shrubs were monitored for amount of canopy dieback, rate of recovery, and seed set for three growing seasons after the freeze event.ResultsShrubs rapidly suffered a nearly complete loss of canopy leaf area across all sites. Although canopy loss was high, mortality was low and 99% of shrubs resprouted during the first growing season after the freeze event. Regrowth rates were similar within ecotone and shrubland sites, even when damage by frost was larger in the latter. After three years of recovery, L. tridentata canopies had regrown on average 23–83% of the original pre‐freeze canopy sizes across the sites.ConclusionsWe conclude that isolated extreme cold events may temporarily decrease shrubland biomass but they do not slow or reverse shrub expansion. These events are less likely to occur in the future as regional temperatures increase under climate change.

Inflationary spectral tilts as a result of the dilatation symmetry breaking

We derive the spectral indices and their runnings of single inflation models by a new approach. We perform a dilatation transformation to the linear cosmological perturbations and derive a current (non-)conservation law. Using it, we construct a dilatation charge and a Ward-Takahashi identity for the two-point correlators, and derive two \textit{exact} expressions for the tree-level spectral indices. First, we apply the slow roll expansion to one of the exact expressions. We calculate the spectral indices and their runnings up to the second and the third order of slow roll parameters respectively, with use of the "horizon crossing formalism". By construction, our results are more rigorous and generic than the previous works. Then, we analyze another exact expression to understand how the perturbations and the slow roll parameters contribute to the spectral indices. By a numerical calculation, we confirm that only the behaviors of the slow roll parameters during a few e-folds around the horizon crossing affect significantly to the values of spectral indices. The analysis in this article indicates that if one cannot use the slow roll parameters, regardless of their values, as the expansion parameters around the horizon crossing, then one can no longer apply the slow roll expansion to the spectral indices, and it is thus necessary to apply the more generic method introduced here.

Specialty services offered by pharmacists in the community

In a recent IJHPR article, Schwartzberg and colleagues report on clinical and other specialty services offered by pharmacists in the community in Israel and in the international arena. The article covers examples of activities recently introduced due to legislative changes which expanded the pharmacist’s scope of practice, along with obstacles that are serving to slow broader expansion and availability of these services. This commentary details the success of clinical pharmacy services being provided by the United States Veterans Health Administration, and offers a framework of elements that support clinical pharmacy practice expansion.