Multi-tiered Structures Research Articles

LAYING AND PRESERVATION OF HENS OF THE INDUSTRIAL FLOCK DEPENDING ON THE DENSITY OF THEIR PLACEMENT IN CAGE BATTERIES

The relevance of this study is conditioned upon the lack of experimentally based data on optimising the density of laying hens of modern egg crosses in cage batteries of new multi-tiered structures. The purpose of this study was to determine the effect of the density of keeping chickens of an industrial herd in cages of 12-tier batteries on their egg production and safety. For this purpose, laying hens of 3 groups of the Hy-Line W-36 industrial flock of crossbreeds were kept in separate similar poultry houses, but at different densities. In particular, the hens of the 1st group were placed in cages at a density of 23 heads/m2 according to the norms, and the 2nd and 3rd groups – at 26 and 28 heads/m2, respectively, i.e., at a density of 13.0% and 21.7%. According to the characteristics of this cross, the laying capacity of hens of an industrial flock should be at least 262.2 eggs per initial laying hen for 62 weeks of life. However, in hens of Group 1, it was 231.4 pcs./head, i.e., it was 11.7% against the background of 5.1% lower preservation, which, if optimal paratypic conditions of existence were created, would correspond to the normative level (96.0%). When the density of housing was increased to 26 heads/m2 (Group 2) and to 28 heads/m2 (Group 3), the laying ability of hens was 220.8 pieces/head and 227.2 units/head with retention of 91.1% and 88.4%, respectively. An increase in the planting density of chickens of the 2nd and 3rd groups led to a decrease in egg production and safety but yielded more production per 1 m2 of production areas. Additionally, 3.9-12.9 million eggs were obtained during the 43 weeks of the productive period, including 1.6-5.3 thousand per 1 m2 of their area. Thus, the specified compaction can be applied as a technological method of rapidly increasing the production of edible eggs without the construction of new or reconstruction of existing farms in case of an added need for this product in the Ukrainian or foreign food markets

Celebrating 100 Years of California History

Celebrating 100 Years of <i>California History</i>

Effects of Rearing Aviary Style and Genetic Strain on the Locomotion and Musculoskeletal Characteristics of Layer Pullets.

Simple SummaryConsumer trends have led to the popularisation of eggs from hens housed in non-cage systems. Aviaries are common non-cage systems that consist of multi-tiered structures with essential resources located within. Being a ground-dwelling species, laying hens must learn when they are young to navigate aviaries, and develop the strength to do so. However, there are different styles of aviaries with varying degrees of structural complexity in which young laying hens (pullets) are reared. This study examined the differences in locomotion and musculoskeletal characteristics of white- and brown-feathered strains of pullets housed in three different styles of rearing aviaries (low, moderate, and high structural complexity) on commercial farms. Pullets in the most complex system spent the most time locomoting, and white-feathered strains in the highly complex systems performed the most jumps and flights. While there were no differences in muscle weights between aviary styles, white-feathered strains, and pullets in the most complex aviary had stronger leg bones than brown-feathered strains and pullets in the least complex system. These results indicate that the style of the aviary in which pullets are reared can affect their bone strength, most likely through differences in the load-bearing exercises performed.Previous research indicates that the musculoskeletal development of pullets is improved when pullets are reared in aviaries compared to conventional rearing cages. However, there are considerable differences in rearing aviary design. To measure locomotion and musculoskeletal development of brown (n = 7) and white-feathered (n = 8) strains of pullets, 15 commercial flocks in three styles of rearing aviaries differing in structural complexity (n = 5 per style) were visited three times: 25.9 ± 6.67, 68.0 ± 4.78, and 112.1 ± 3.34 days of age. Locomotion (duration of standing, sitting, walking, running, flying, and rates jumping, flying, group running and walking) was analysed from videos recorded three times per day: at the beginning, middle, and end of the light cycle. Pullets for dissection were taken on visits 2 and 3. Pullets in the most complex system (style 3; S3) spent the most time locomoting throughout rearing (p < 0.05). Pullets in S3, particularly white-feathered strains, performed the highest rate of vertical transitions (p < 0.05). There were no differences in any of the proportional muscle weights between aviaries styles (p > 0.05) despite the differences in locomotion. White-feathered strains, however, had proportionally heavier pectoralis major (p < 0.0001), pectoralis minor (p < 0.0001), and lighter leg muscles (p < 0.0001) than brown-feathered strains. White-feathered strains and pullets in S3 also had proportionally stronger tibiae and femurs than brown-feathered strains and pullets housed in the least structurally complex system (style 1; S1) (p < 0.05). However, there were no differences found in the breaking strength of the radius and humerus between strain colours or aviary styles (p < 0.05). Therefore, strain, as well as differences in rearing aviary design, can affect the types of locomotion that growing pullets perform, which may, in turn, impact their skeletal development.

Power and Sample Size Determination for Multilevel Mediation in Three-Level Cluster-Randomized Trials

Mediation analyses supply a principal lens to probe the pathways through which a treatment acts upon an outcome because they can dismantle and test the core components of treatments and test how these components function as a coordinated system or theory of action. Experimental evaluation of mediation effects in addition to total effects has become increasingly common but literature has developed only limited guidance on how to plan mediation studies with multi-tiered hierarchical or clustered structures. In this study, we provide methods for computing the power to detect mediation effects in three-level cluster-randomized designs that examine individual- (level one), intermediate- (level two) or cluster-level (level three) mediators. We assess the methods using a simulation and provide examples of a three-level clinic-randomized study (individuals nested within therapists nested within clinics) probing an individual-, intermediate- or cluster-level mediator using the R package PowerUpR and its Shiny application.

Integration processes in knowledge-intensive industries of the Russian economy (using the aircraft industry as an example)

The aim of this article is to examine integration processes taking place in knowledge-intensive sectors of the modern Russian economy in terms of their history and to evaluate them using methods of economic analysis. The article identifies three phases of development of knowledge-intensive sectors of the Russian economy: the Soviet phase, the phase of transformation (from the early 1990s to mid-2000s) and the present one, which can be roughly described as a quasi-nationalization phase. Furthermore, the authors of the article discuss the advantages and disadvantages of the Soviet experience in managing high-tech industries; analyse typical mistakes, which were made during the privatization of knowledge-intensive enterprises and their consequences for the Russian economy and reveal the main problems and risks associated with the policy of creating tightly integrated multi-tiered structures, which stay under control of the state. The article presents figures describing changes in financial indicators relating to a number of integrated structures in high-tech industries.

Two- and Three-Tiered Stacked Architectures by Covalent Assembly.

Simple discotic cores functionalized with reactive arms have been assembled into two- and three-tiered covalent stacks through imine formation. The targets are obtained in good yields, but competing formation of misassembled byproducts highlights some of the challenges inherent to the thermodynamically controlled assembly of rigid, compact, three-dimensional architectures. The structures comprise a central stack of arenes surrounded by a triple helix of interconnected arms. The racemization rate is strongly dependent on the number of tiers, suggesting cooperative conformational coupling in these multi-tiered structures.

Hierarchical Proteinosomes for Programmed Release of Multiple Components.

A facile route to hierarchically organized multicompartmentalized proteinosomes based on a recursive Pickering emulsion procedure using amphiphilic protein-polymer nanoconjugate building blocks is described. The number of incarcerated guest proteinosomes within a single host proteinosome is controlled, and enzymes and genetic polymers encapsulated within targeted subcompartments to produce chemically organized multi-tiered structures. Three types of spatiotemporal response-retarded concomitant release, synchronous release or hierarchical release of dextran and DNA-are demonstrated based on the sequential response of the host and guest membranes to attack by protease, or through variations in the positioning of disulfide-containing cross-links in either the host or guest proteinosomes integrated into the nested architectures. Overall, our studies provide a step towards the construction of hierarchically structured synthetic protocells with chemically and spatially integrated proto-organelles.

Evicase: an evidence-based case structuring approach for personalized healthcare.

The personalized medicine era stresses a growing need to combine evidence-based medicine with case based reasoning in order to improve the care process. To address this need we suggest a framework to generate multi-tiered statistical structures we call Evicases. Evicase integrates established medical evidence together with patient cases from the bedside. It then uses machine learning algorithms to produce statistical results and aggregators, weighted predictions, and appropriate recommendations. Designed as a stand-alone structure, Evicase can be used for a range of decision support applications including guideline adherence monitoring and personalized prognostic predictions.

Impact of polymer curing on two-dimensional and three-dimensional shape change in nanoimprint lithography

Polymer shrinkage from curing in nanoimprint lithography (NIL) strongly affects the ultimate shapes of two- and three-dimensional structures produced following etching. We computationally study the curing step in the NIL process and predict the shape changes caused by polymer shrinkage. The shape changes are predicted for crosses, diamonds with sharp and rounded tips, and multitiered structures that are applicable for multibit memory devices and dual damascene processes. The shape changes from curing are shown to be governed by the shrinkage coefficient of the polymer resist, its Poisson’s ratio, and the geometric aspect ratios of the shapes. Finite element simulations demonstrate that shape change due to polymer densification is equal to the average volumetric contraction of the resist material, but shrinkage is not isotropic and vertical displacement dominates. The thickness of the residual layer does not impact the final profile of the imprinted shapes considered. Further analysis shows that diamonds with sharp tips stay sharp while the tips of rounded diamonds get sharper. Additionally, shape changes for multitiered structures are not uniformly distributed among the tiers. Using etch simulations, we demonstrate the significant impact of polymer shrinkage on the final feature profile.

Интеграционные процессы в наукоемких отраслях российской экономики

This article is devoted to the study of integration processes taking place in&#x0D; knowledge-intensive sectors of the modern Russian economy. The authors&#x0D; of the article analyze typical mistakes, which were made during the privatization&#x0D; of knowledge-intensive enterprises and their consequences for the Russian&#x0D; economy; reveal the main problems and risks associated with the policy of&#x0D; creating tightly integrated multi-tiered structures, which stay under control&#x0D; of the state. The article presents figures describing changes in financial&#x0D; indicators of a number of integrated structures in high-tech industries.

Rapid Fabrication of Bio‐inspired 3D Microfluidic Vascular Networks

Adv. Mater. 2009, 21, 3567–3571 2009 WILEY-VCH Verlag G N Living systems face a fundamental challenge of orchestrating exchange of nutrients and oxygen throughout 3D space in order to satisfy their metabolic needs. In nature, vascular networks have evolved to elegantly address this problem by incorporating highly branched fractal-like architectures that are efficiently space-filling while minimizing the energy required to sustain transport. The ability to mimic these features in vitro would be immensely beneficial in the field of tissue engineering, where diffusion limitations generally restrict the maximum thickness of constructs to a few hundred microns. Here, we address this need by introducing a nearly instantaneous method to embed branched 3D microvascular networks inside plastic materials. In thismicrofabrication process, a high level of electric charge is first implanted inside a polymer dielectric using electron beam irradiation. The accumulated energy is then discharged in a controlled manner to locally vaporize and fracture the material, leaving behind a network of branched microchannels arranged in a tree-like architecture with diameters ranging from 10mm to 1mm. Modulating the irradiation profile and discharge locations allows the networks’ morphology and interconnectivity to be precisely tailored. Interconnected networks with multiple fluidic access points can be straightforwardly constructed, and quantification of their branching characteristics reveals remarkable similarity to naturally occurring vasculature. This method can be applied in a variety of polymers, and may help enable production of organ-sized tissue scaffolds containing embedded vasculature. The hierarchy of length scales that comprise vascular networks (ranging from mm–mm in diameter) and the need for these structures to be widely accessible throughout a sizeable 3D volume present significant manufacturing challenges. Photolithography-based microfabrication technology has been extensively examined as a potential avenue to address some of these issues. Here, planar micromachining is harnessed to produce 2D microchannel arrays that can be stacked in a layer-by-layer fashion to achieve a limited degree of threedimensionality. But assembly of large-scale multi-tiered structures is tedious, and the inherently planar nature of the individual layers restricts the network’s topological complexity. More recent developments have enabled fully 3D flow architectures to be produced using methods including solid freeform fabrication, stereolithography, and direct printing. But these approaches generally involve time consuming serial processes, and the optimal range of feature sizes associated with each technology is often relatively narrow. Many of these processes are also challenging to scale up toward levels feasible for mass production. We have developed a fabrication method that uniquely overcomes these limitations, enabling branched 3D microvascular networks incorporating a wide range of microchannel diameters to be rapidly constructed in a variety of plastic materials (Fig. 1). This process harnesses electron beam irradiation to implant a high level of electric charge inside a substrate so that the energy released upon discharge will be sufficiently intense to locally vaporize and fracture the surrounding material. In this way, networks of highly branched tree-like microchannels are produced that become permanently embedded within the substrate. The formation and growth of these electrostatic discharge structures (i.e., Lichtenberg figures or Lichtenberg trees) are analogous to lightning phenomena that occur during thunderstorms when charge accumulation within clouds exceeds the breakdown potential of the surrounding atmosphere. We first explored applying this process to construct 3D vascular microchannel networks in acrylic plastic substrates by irradiating blocks of polished poly(methyl methacrylate) (PMMA) using a 10MeVelectron beam to implant a prescribed charge distribution (typical space charge densities are on the order of 1mC cm ), after which the energized blocks were discharged by one of two methods. In the first approach (Fig. 1a), release of the accumulated charge was achieved by striking the irradiated block with the sharp tip of a grounded electrode. The point source of electrical grounding and the mechanical stress associated with the physical impact of striking the block combine to produce an immediate and rapid energy release. Alternatively, a defect (e.g., a small hole 1mm in diameter) was intentionally introduced on the surface of the block prior to irradiation that served as a nucleation site for spontaneous discharge upon exposure to the electron beam without the need for further physical contact (Fig. 1b). In either case, the rapid and intense release of electrostatic energy instantaneously generated a hierarchically branched microchannel array penetrating throughout the entire volume of the block and originating from either the point of contact with the grounded electrode or the nucleation site created on the surface (Fig. 1c and Supporting Information Movie 1). Networks formed using the grounded contact method

Taking Engineering's Pulse

This article highlights key points of the Mechanical Engineering Global Summit. According to the participants, much of the future for mechanical engineers will involve integrating systems of all kinds. Throughout the discussions at the meeting, numerous comments concerned the increasingly interdisciplinary nature of engineering practice. Experts believe that vertical farms, for instance, could use hydroponics and other means to take farming indoors, where it could be carried out in multitiered structures. If technology like this could be made practical, it could multiply the area available for agriculture. A multibillion-dollar experiment in sustainable living has been proposed for the United Arab Emirates. The initiative hopes to create a high-tech city that will have zero emissions and be entirely self-sustaining. One of the proposals is to restructure engineering education and to prepare engineers the way lawyers and doctors are trained: a four-year liberal arts education in preparation for the professional degree in postgraduate study.

A Simple Imprint Method for Multi‐Tiered Polymer Nanopatterning on Large Flexible Substrates Employing a Flexible Mold and Hemispherical PDMS Elastomer

AbstractThis work reports a facile method to fabricate multi‐tiered polymer nanopatterns on SU‐8 by the combination of imprint‐ and photo‐lithography. First, SU‐8 is imprint patterned using a polymeric flexible mold with an anti‐adhesion coating that is deposited on a transparent and flexible substrate, at room temperature under low pressure. Next, the resulting SU‐8 nanopatterns are exposed to UV light through a chromium mask by a photolithographic process. Removal of the unexposed SU‐8 leaves behind multi‐tiered structures. The use of a hemispherical poly(dimethylsiloxane) pad facilitates the evacuation of trapped air during the imprinting process. Line/space patterns of 500 nm with the smallest line width of 200 nm were homogeneously imprint‐patterned on SU‐8 on a large flexible substrate, and three‐tiered structures, ranging in thickness from 300 nm to 2 µm, were successfully formed.magnified image

Kissing the Old Class Politics Goodbye

Verity Burgmann's call for a reinvigorated class politics and language is timely. This essay shares her goal of strengthening social movements in which class is taken seriously. It argues, however, that her efforts to resuscitate an antiquated class politics dressed up in identity clothes will not further that goal. This response offers an alternative reading of the nature and history of the “new” and the “old” social movements, of what can be learned about class and class-conscious movements from “identity politics” and from cultural theorists, and of what is needed to encourage future movements for social and economic justice. It calls for a class politics that recognizes the diversity of the working classes, embraces multiple class identities, reflects the fluid and multitiered class structures in which we live, and honors the aspirations of working people for inclusion, equity, and justice.

Improved step and flash imprint lithography templates for nanofabrication

Step and flash imprint lithography (SFIL) is an attractive method for printing sub-100 nm geometries. Relative to other imprinting processes, SFIL has the advantage that the template is transparent, thereby facilitating conventional overlay techniques. In addition, the imprint process is performed at low pressures and room temperature, which minimizes magnification and distortion errors. Several different methods for fabricating templates are presented in this study. One scheme addresses some of the weaknesses associated with a solid glass substrate by incorporating a conductive and transparent layer of indium tin oxide (ITO) on the surface of the substrate. Features are defined on the templates by patterning a thin layer of PECVD oxide that is deposited on the ITO layer. A second method bypasses the oxide etch process by imaging a thin layer of hydrogen silsesquioxane (HSQ). By using a combination of these two methods, it is also possible to form multi-tiered structures on a template. Templates with features as small as 20 nm have been fabricated using the methods described above. The templates were then used to imprint patterns on 200 mm silicon wafers. It appears that any feature defined in the template is faithfully replicated on the wafer.

Fabrication of multi-tiered structures on step and flash imprint lithography templates

Step and flash imprint lithography (SFIL) replicates patterns by using a transparent template with relief images etched into its surface. Recent work has examined alternative methods for template fabrication. One scheme incorporates a conductive and transparent layer of indium tin oxide (ITO) on the surface of the substrate. Features are defined on the templates by patterning a thin layer of PECVD oxide that is deposited on the ITO layer. A second method bypasses the oxide etch process by imaging a thin layer of hydrogen silsesquioxane (HSQ). By combining or iterating the two methods, it is possible to form multi-tiered structures on a template. Two and three tier structures were fabricated on silicon wafers and templates. A two layer structure was fabricated on a quartz photoplate by patterning PECVD oxide and subsequently patterning a second tier using HSQ. The resulting relief structures were successfully replicated on wafers using SFIL.

Numerical solution of static problems for multitiered structures

A linear stress—strain analysis is made of a structure consisting of two discretely reinforced cylindrical shells and an intermediate conical shell with large openings, which is simulated by a three-dimensional framework. This three-tier system is under longitudinal and local flexural loads. The calculations are made by the finite-difference method using modified equations of the mixed method for shells and by the deformation method for the framework. Two forms of the structure differing by specified parameters are studied

Network management evolution

Developments such as multi-tiered network structures, hybrid communication architectures, integrated voice/data resources and the recent implementations of T1 and integrated digital networks, have brought to light the inadequacies of existing network management tools and techniques — as has the increased usage of local area networks and private branch exchanges. Certain communication networks, hampered by these inadequacies, have become unmanageable. Small evolutionary steps are no longer satisfactory for the task of meeting the users' expectations of high standards of service. After examining the requirements for network management, and the inadequacies of existing methods, the author defines network management subsystems. Critical success factors, such as methodology, instrumentation and human resources are discussed. Finally, directions for network management — such as centralization, integration, automation, cooperation between manufactures, and standardization — are addressed.