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Water is essential for all active life processes. Despite this, there are a number of organisms that can survive prolonged desiccation. The vitrification hypothesis posits that such organisms survive desiccation by forming non-crystalline amorphous (vitrified) solids, often through the accumulation of protective disaccharides. In line with this theory, vitrification has been shown to be essential for desiccation tolerance in many organisms that survive extreme drying. However, it is known that not all vitrified materials are protective and that certain physio-chemical properties correlate with the protection in the glassy state. Furthermore, recent evidence suggests that the physio-chemical properties that correlate with protection can vary depending on the chemical nature of similarly sized protectants. While the chemistry of protectants has been probed in relation to the protective properties they induce when vitrified, the effect of protectant size on glassy properties and protection during drying has not been investigated. Here, we study the effect of the polymer size of sucrose on glassy properties associated with protection in the vitrified state. The monomer sucrose, and the polymers polysucrose 70 and polysucrose 400 (70 and 400 refer to the molecular weight of the polymers in kDa). Using these three different-sized sucrose polymers, we find that each of the glassy properties we investigated including; enzyme protection, water content, glass transition temperature, and glass former fragility, were affected by polymer size. However, only one vitrified property, glass transition temperature, correlated with protection during drying. This correlation is heavily dependent on sucrose polymer size. Increased glass transition midpoint temperature correlated positively with protection conferred by monomeric sucrose (p-value = 0.009, R2 = 0.840), whereas this correlation was bi-phasic for polysucrose 70, and had an inverse relationship for polysucrose 400 (p-value = 0.120, R2 = 0.490). Our results indicate that the size of vitrifying protectants can have a profound effect on glassy properties as well as on how these properties correlate with protection in the dry state. Beyond desiccation tolerance, these findings provide insights for the development of new technologies for the stabilization of biological material in the dry state. [ABSTRACT FROM AUTHOR]

BackgroundOcular albinism type 1, an X-linked disease characterized by the presence of enlarged melanosomes in the retinal pigment epithelium (RPE) and abnormal crossing of axons at the optic chiasm, is caused by mutations in the OA1 gene. The protein product of this gene is a G-protein-coupled receptor (GPCR) localized in RPE melanosomes. The Oa1-/- mouse model of ocular albinism reproduces the human disease. Oa1 has been shown to immunoprecipitate with the Gαi subunit of heterotrimeric G proteins from human skin melanocytes. However, the Gαi subfamily has three highly homologous members, Gαi1, Gαi2 and Gαi3 and it is possible that one or more of them partners with Oa1. We had previously shown by in-vivo studies that Gαi3-/- and Oa1-/- mice have similar RPE phenotype and decussation patterns. In this paper we analyze the specificity of the Oa1-Gαi interaction.MethodologyBy using the genetic mouse models Gαi1-/-, Gαi2-/-, Gαi3-/- and the double knockout Gαi1-/-, Gαi3-/- that lack functional Gαi1, Gαi2, Gαi3, or both Gαi1 and Gαi3 proteins, respectively, we show that Gαi3 is critical for the maintenance of a normal melanosomal phenotype and that its absence is associated with changes in melanosomal size and density. GST-pull-down and immunoprecipitation assays conclusively demonstrate that Gαi3 is the only Gαi that binds to Oa1. Western blots show that Gαi3 expression is barely detectable in the Oa1-/- RPE, strongly supporting a previously unsuspected role for Gαi3 in melanosomal biogenesis.ConclusionOur results identify the Oa1 transducer Gαi3 as the first downstream component in the Oa1 signaling pathway.

Copyright of Archivos de Cardiología de México is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A prototype silicon-on-silicon field programmable multichip module (FPMCM) has a 40 K gates capacity and 256 user IO limit. The capacity is four times greater than that of the other field programmable logic devices (FPLDs) and the device functioning is cost-effective. There is a significant reduction in the area of PCB-based field programmable systems. The MCM technologies offer various advantages in the area of operations of integrating FPLD's and field programmable systems by significantly enhancing the capability of the devices.

Background: Invasive mechanical ventilation (IMV) has become one of the mainstays of therapy in NICUs worldwide, as a result of which premature babies with extremely low birth weight have been able to survive. Although lifesaving, IMV can result in lung inflammation and injury. Surfactant therapy is considered a standard of care in preterm infants with immature lungs. Recently, small molecule inhibitors like siRNAs and miRNAs have been used for therapeutic purposes. Ddit3 (CHOP), Ang2 and miR34a are known to be upregulated in experimental lung injury. We wanted to test whether inhibitors for these molecules (CHOP siRNA, Ang2 siRNA, and miR34a antagomir) if used alone or with a combination with surfactant (Curosurf®) would help in reducing ventilation and hyperoxia-induced injury in an experimental lung injury model. Methods: Preterm rabbits born by cesarean section were intratracheally instilled with the three small molecule inhibitors with or without Curosurf® prior to IMV and hyperoxia exposure. Prior to testing the inhibitors in rabbits, these small molecule inhibitors were transfected in mouse lung epithelial cells (MLE12 and AECII) and delivered to neonatal mouse pups intranasally as a proof of concept that surfactant (Curosurf®) could be used as an effective vehicle for administration of such drugs. Survival, pulmonary function tests, histopathology, immunostaining, quantitative PCR and western blotting were done to see the adjuvant effect of surfactant with these three small molecule inhibitors. Results: Our data shows that Curosurf® can facilitate transfection of small molecules in MLE12 cells with the same and/or increased efficiency as Lipofectamine. Surfactant given alone or as an adjuvant with small molecule inhibitors increases survival, decreases IMV and hyperoxia-induced inflammation, improves pulmonary function and lung injury scores in preterm rabbit kits. Conclusion: Our study shows that Curosurf® can be used successfully as an adjuvant therapy with small molecule inhibitors for CHOP/Ang2/miR34a. In this study, of the three inhibitors used, miR34a inhibitor seemed to be the most promising compound to combat IMV and hyperoxia-induced lung injury in preterm rabbits. [ABSTRACT FROM AUTHOR]

We report on a novel pump-probe photothermal system based on the self-mixing effect. Experimental observations using a single mode laser show that the photothermal lens distorts the self-mixing beam propagation, thus modulating the light re-injected in the laser cavity and producing fluctuations in the output power. Moreover, a linear dependence of power amplitude oscillations as a function of the photothermal parameters is observed, enabling determination of Fe(II) concentrations at parts-per-trillion levels. A theoretical model is presented to describe the self-mixing signal as a function of the photothermal parameters, which explains essential features of the experimental results. The proposed thermal-lens self-mixing system provides much higher accuracy and sensitivity over a wide set of measurements as compared to the conventional thermal lens spectroscopy. [ABSTRACT FROM AUTHOR]

The Monteith Formation is an important tight gas reservoir in the Deep Basin, Alberta, and consists of a progradational succession of shallow marine sediments, nonmarine carbonaceous and coaly, coastal plain facies, and coarse-grained fluvial deposits, from base to top, respectively. This study is based on multiscale description and characterization techniques with cores and drill cuttings, including multimethods laboratory measurements of key reservoir parameters such as porosity and permeability. A second stage of the study involves the use of laboratory measurements obtained from cores and drill cuttings and their integration with well logs to construct a numerical 3D model of the study area. The 3D model is used to history match gas production, and forecast performance of new wells in those areas where the geologic model indicates potential for gas production. The ultimate goal is to provide a better understanding of the distribution of reservoir properties in the study area for developing drilling prospects and their production potential in areas where reliable data are scarce. The reservoir-modeling stage is carried out by implementing a recently developed methodology that integrates a variable shape distribution (VSD) model, capable of capturing different reservoir properties throughout the whole scale spectrum without any data truncation. Truncation is the excuse generally used for eliminating information that does not fit a given distribution. The claim is that the data are of poor quality, something that is not true in many cases. This new methodology eliminates the need for truncation, and introduces an extension of the VSD approach for reservoir-simulation purposes that reduces uncertainty in the generation of drilling prospects. Core analysis shows that the Monteith A member is composed of complex fluvial-dominated deposits with better rock quality than the shallow marine sandstones of the Monteith C member. This is most likely because of larger pore-throat apertures that range between 0.5 and 1 μm, and a relatively higher proportion of preserved intergranular pore space within these coarser-grained framework grains. Furthermore, the best production performance is from wells that are producing from the Monteith A. Variability of production rates also seems to be controlled by the presence of natural fractures. It is anticipated that the resulting 3D reservoir model will allow improving field-development strategies for this and other similar unconventional gas reservoirs in the Deep Basin of Alberta and elsewhere. [ABSTRACT FROM AUTHOR]

Production of shale and tight oil is the cornerstone of the United States race for energy independence. According to the US Energy Information Administration, approximately 90% of the oil-production growth comes from six tight-oil plays. The Eagle Ford is one of these plays, and it accounts for 33% of the oil-production growth with a contribution of 1.3 million B/D. This is outstanding. However, oil recoveries as a percentage of the original oil in place (OOIP) are extremely low. This must be improved. A geological challenge in the Eagle Ford shale is the understanding of unconventional fluids distribution over geologic time: Shallower in the structure, there is black oil; deeper and to the south; condensate appears; and at the bottom, dry gas can be found. Differences in burial depth, temperature, and vitrinite reflectance are used to explain this unique distribution. A similar fluid distribution occurs in other unconventional reservoirs (e.g., Duvernay shale in Canada). The low oil recovery and the unusual distribution of fluids led to the key objective of this paper--to identify the main factors that control fluid migration (caused by buoyancy of gas in oil) from one zone to another through geologic time. This was performed by constructing a conceptual cross-sectional compositional simulation model with northwest/southeast orientation that allowed the study of fluid migration, fluid distribution, and fluid contacts throughout 1 million years while maintaining computational time within reasonable limits. The controlling parameters studied were porosity, permeability, pore-throat aperture (rp35), and spacing between natural fractures. Results show that fluids in the matrix remained with approximately the same original distribution (i.e., approximately the same dry-gas/condensate contact and approximately the same condensate/oil contact). These fluids are the target of an ongoing research project with the ultimate goal of improving oil recovery from tight reservoirs by means of enhanced oil recovery (EOR) (Fragoso et al. 2015). There is, however, some gas migration through natural fractures to the top of the structure. This migration is interpreted in this study to be responsible for higher initial gas production in some oil wells in the top of the structure. Some operators indicate, however, that rapid gas/oil-ratio increases in the updip oil region are the result of low reservoir pressures and the rapid onset of two-phase flow. It would probably take geochemical evidence to support this conclusion. [ABSTRACT FROM AUTHOR]

Copyright of Revista Miradas is the property of Universidad Tecnologica de Pereira and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Provides a list of the frequencies of minority group topics presented during the first ten years of the American Mental Health Counselors Association (AMHCA) Journal. Percentage of minorities in the labor market; Discussion on the list of frequencies of minority group; Limitations of the study.

Assesses the outcome of assertiveness training as manifested in the effectiveness of the trainees' counseling in the U.S. Difference between experimental and control groups' clients on depression level following counseling; Use of behavioral ratings for the measure of assertiveness; Importance of degree of attainment of objectives for a counselor to assume a client caseload.

Copyright of Insectes Sociaux is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Information about the specific history of gay and lesbian representation discussed at the UCLA Gay and Lesbian Media conference is presented. Topics include the essentialist idea about the nature of femininity, masculinity and homosexuality in the way of developing theories to account for the complexities of representation. Also discussed in the conference is the representation of gays which could be viewed as an object for historical and theoretical inquiry.

The article focuses on property tax purposes and the use and misuse of transaction data in its valuation preparations. The market information from mergers or acquisitions is used by the property tax assessors as proof of of a taxpayer company's taxable unit and its fair market value. All of a taxpayer's operating assets collectively are valued by the unit valuation methods.

Cellular desiccation - the loss of nearly all water from the cell - is a recurring stress in an increasing number of ecosystems that can drive proteome-wide protein unfolding and aggregation. For cells to survive this stress, at least some of the proteome must disaggregate and resume function upon rehydration. The molecular determinants that underlie the ability of proteins to do this remain largely unknown. Here, we apply quantitative and structural proteomic mass spectrometry to desiccated and rehydrated yeast extracts to show that some proteins possess an innate capacity to survive extreme water loss. Structural analysis correlates the ability of proteins to resist desiccation with their surface chemistry. Remarkably, highly resistant proteins are responsible for the production of the cell's building blocks - amino acids, metabolites, and sugars. Conversely, those proteins that are most desiccation-sensitive are involved in ribosome biogenesis and other energy consuming processes. As a result, the rehydrated proteome is preferentially enriched with metabolite and small molecule producers and depleted of some of the cell's heaviest consumers. We propose this functional bias enables cells to kickstart their metabolism and promote cell survival following desiccation and rehydration.

In this work, we introduce a modified hologram plane constraint to improve the accuracy of the global Gerchberg-Saxton (GGS) algorithm used for multiplane phase-only hologram generation. This constraint consists of a modified phase factor that depends on the amplitude of the field in the hologram plane. We demonstrate that this constraint produces an increase in the mean correlation coefficient between the reconstructed planes from a multiplane hologram and the corresponding amplitude targets for each plane. Furthermore, this constraint can be applied together with a mixed constraint in the reconstruction planes, leading to a more uniform and controllable reproduction of a target intensity distribution. To confirm the validity of our proposal, we show numerical and experimental results for multiplane holograms with six discrete planes, using both high and low contrast targets. For the experimental results, we implement a holographic projection scheme based on a phase-only spatial light modulator.

We propose for the first time, to the best of our knowledge, the use of optimized random phases (ORAPs) in a double random phase encryption scheme (DRPE). In DRPE schemes the convolution between two random phase functions encrypts the information to be secured. However, in actual encryption applications, this convolution of random phases also results in unwanted effects like speckle noise. In this Letter we show that under certain conditions this noise can be drastically reduced. These conditions can be easily achieved by using ORAPs. These ORAPs, besides containing information about the parameters of the optical system and maintaining all the security properties of a random phase function, ensure that the encrypted data is a phase-only function. This leads to a great increase in system performance, with decryption quality similar to the reconstruction of a phase-only hologram generated with the Gerchberg-Saxton algorithm. We show both numerical and experimental results confirming the validity of our proposal.

We propose a simple and efficient technique capable of generating Fourier phase only holograms with a reconstruction quality similar to the results obtained with the Gerchberg-Saxton (G-S) algorithm. Our proposal is to use the traditional G-S algorithm to optimize a random phase pattern for the resolution, pixel size, and target size of the general optical system without any specific amplitude data. This produces an optimized random phase (ORAP), which is used for fast generation of phase only holograms of arbitrary amplitude targets. This ORAP needs to be generated only once for a given optical system, avoiding the need for costly iterative algorithms for each new target. We show numerical and experimental results confirming the validity of the proposal.

This article presents the design and implementation of a controller scheme for efficient resource management in Advanced Life Support Systems. In the proposed approach, a switching hybrid system model is used to represent the dynamics of the system components and their interactions. The operational specifications for the controller are represented by utility functions, and the corresponding resource management problem is formulated as a safety control problem. The controller is designed as a limited-horizon online supervisory controller that performs a limited forward search on the state-space of the system at each time step, and uses the utility functions to decide on the best action. The feasibility and accuracy of the online algorithm can be assessed at design time. We demonstrate the effectiveness of the scheme by running a set of experiments on the Reverse Osmosis (RO) subsystem of the Water Recovery System (WRS).

This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.