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941.
Coral reefs are threatened worldwide, with environmental stressors increasingly affecting the ability of reef-building corals to sustain growth from calcification (G), photosynthesis (P) and respiration (R). These processes support the foundation of coral reefs by directly influencing biogeochemical nutrient cycles and complex ecological interactions and therefore represent key knowledge required for effective reef management. However, metabolic rates are not trivial to quantify and typically rely on the use of cumbersome in situ respirometry chambers and/or the need to remove material and examine ex situ, thereby fundamentally limiting the scale, resolution and possibly the accuracy of the rate data. Here we describe a novel low-cost in situ respirometry bag that mitigates many constraints of traditional glass and plexi-glass incubation chambers. We subsequently demonstrate the effectiveness of our novel “Flexi-Chamber” approach via two case studies: 1) the Flexi-Chamber provides values of P, R and G for the reef-building coral Siderastrea cf. stellata collected from reefs close to Salvador, Brazil, which were statistically similar to values collected from a traditional glass respirometry vessel; and 2) wide-scale application of obtaining P, R and G rates for different species across different habitats to obtain inter- and intra-species differences. Our novel cost-effective design allows us to increase sampling scale of metabolic rate measurements in situ without the need for destructive sampling and thus significantly expands on existing research potential, not only for corals as we have demonstrated here, but also other important benthic groups.  相似文献   
942.
Abstract

We have developed and evaluated methods for the production of highly pure oligonucleotides.

Presently the solid phase synthesis in an automated DNA synthesiser applying the phosphoramidite chemistry can be regarded as a standard. During the synthesis several undesirable by-products arise:

- incomplete coupling (1%) leads to 5′-truncated sequences. These sequences are acetylated at their 5′-hydroxyl group to prevent further elongation in subsequent coupling steps, but this “capping step” is incomplete, the capping-yield is 90%, leading to accumulation of sequences of the length n-1 with internal deletions.

- the glycosidic bond to N-protected purines, especially adenine, is susceptible to acid leading to depurination and subsequently to strand scission during alkaline deprotection of the oligonucleotide. This gives rise to 3′- and to 5′-truncated sequences. The 3′-truncated sequences will not be removed by standard Rp HPLC as they are tritylated.

- the reactions involved in synthesis and deprotection may cause base modifications (full length product with damaged bases).

- insufficient deprotection procedures may result in incomplete removal of protecting groups, especially from the bases (full length products with altered bases).

We have set up two different schemes (Fig. 1 and Fig. 2) for synthesis and purification, which should provide highly pure oligonucleotides with the potential of adapting to large scale production:

- accumulation of n-1 sequences (failure of capping) will be avoided by a double capping procedure using phosphite in the first capping step and an acetic anhydride capping reagent in the second capping step, as described in the literature1.

- 3′-truncated sequences are removed by different methqds in the two schemes. In scheme I (Fig. 1) the 3′-truncated sequences can be washed off, as the 3′-full length product still is anchored to the solid support after deprotection. In scheme II (Fig. 2) the 3′truncated sequences are digested by snake venom phosphodiesterase. The 3′-full length product is protected against digestion by a 3′ - 3′-inverted end. An oligo with a correct 3′-end is, in both schemes, eventually obtained by cleaving with RNase between the ribo unit and the requested DNA-sequence.

- 5′-truncated sequences are removed by Rp HPLC using the DMTr group of the last coupling step (trityl-on synthesis) as a hydrophobic tag.

Very labile protecting groups will be used to avoid problems with deprotection.  相似文献   
943.
Recently, associations between facial structure and aggressive behaviour have been reported. Specifically, the facial width-to-height ratio (fWHR) is thought to link to aggression, although it is unclear whether this association is related to a specific dimension of aggression, or to a more generalized concept of dominance behaviour. Similarly, an association has been proposed between facial masculinity and dominant and aggressive behaviour, but, to date, this has not been formally tested. Because masculinity and fWHR are negatively correlated, it is unlikely that both signal similar behaviours. Here, we thus tested these associations and show that: (i) fWHR is related to both self-reported dominance and aggression; (ii) physical aggression, verbal aggression and anger, but not hostility are associated with fWHR; (iii) there is no evidence for a sex difference in associations between fWHR and aggression; and (iv) the facial masculinity index does not predict dominance or aggression. Taken together, these results indicate that fWHR, but not a measure of facial masculinity, cues dominance and specific types of aggression in both sexes.  相似文献   
944.
Oncolytic viruses based on adenovirus type 5 (Ad5) have been developed as a new class of therapeutic agents for cancers that are resistant to conventional therapies. Clinical experience shows that these agents are safe, but virotherapy alone has not achieved long-term cure in cancer patients. The vast majority of oncolytic adenoviruses used in clinical trials to date have deletion of the E3B genes. It has been demonstrated that the antitumor potency of the E3B-deleted mutant (dl309) is inferior to adenovirus with E3B genes intact. Tumors treated with dl309 show markedly greater macrophage infiltration than E3B-intact adenovirus. However, the functional mechanisms for this were not previously known. Here, we demonstrate that deletion of E3B genes increases production of chemokines by monocytes after adenovirus infection and increases monocyte migration. The E3B 14,700-Da protein (E3B-14.7K) inhibits STAT1 function by preventing its phosphorylation and nuclear translocation. The STAT1 inhibitor, fludarabine, rescues the effect of E3B-14.7K deletion by downregulating target chemokine expression in human and murine monocytes and results in an enhanced antitumor efficacy with dl309 in vivo. These findings have important implications for clinical use of E3B-deleted oncolytic adenovirus and other E3B-deleted adenovirus vector-based therapy.  相似文献   
945.
Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine''s performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV). Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb −/− nos2 −/− animals lacking NADPH oxidase and inducible NO synthase. In cybb −/− nos2 −/− mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093), was >1000-fold attenuated in cybb −/− nos2 −/− mice and ≈100 fold attenuated in tnfr1 −/− animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA) response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.  相似文献   
946.
Feathers exhibit an extraordinary diversity of shapes, which are used by birds to accomplish a diverse set of functions. Pennaceous feathers have a double branched morphology that develops from a tube of epidermis, and variation in branch geometry determines feather shape. Feather development is both complex (i.e., a simple developmental modification can have multiple effects on mature feather shape), and redundant (i.e., different developmental modifications can create the same shape). Due to this, it is not readily apparent how different feather shapes develop. In many feathers, barbs are not straight, but instead curve in toward, or away, from the feather tip. Barb curvature can affect the shape of mature feathers but the development of curved barbs is unknown. Previous research has hypothesized that barb curvature could develop either during the helical growth of barb ridges in the tubular feather germ, or during barb angle expansion as the feather unfurls from the sheath. To better understand the development of curved barbs and their effects on mature feathers we present a theoretical model of curved barb development and test the model with empirical investigations of feathers. We find that curved barbs affect many aspects of feather morphology including vane width, barb length, and barb spacing. In real feathers, curved barbs can develop both during helical barb ridge growth and during barb angle expansion, with most of the observed curvature due to barb angle expansion. Our results demonstrate that barb angle expansion as a feather unfurls from the sheath is a complex and dynamic process that plays an important role in determining the shape and structure of mature feathers. Curved barbs create heterogeneity in barb geometry within the feather vane, which could have important implications for aerodynamic function and the development of within feather pigmentation patterns. J. Morphol. 277:995–1013, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
947.
All human diseases involve proteins, yet our current tools to characterize and quantify them are limited. To better elucidate proteins across space, time, and molecular composition, we provide a >10 years of projection for technologies to meet the challenges that protein biology presents. With a broad perspective, we discuss grand opportunities to transition the science of proteomics into a more propulsive enterprise. Extrapolating recent trends, we describe a next generation of approaches to define, quantify, and visualize the multiple dimensions of the proteome, thereby transforming our understanding and interactions with human disease in the coming decade.  相似文献   
948.
Children with autism spectrum conditions (ASC) have major difficulties in recognizing and responding to emotional and mental states in others'' facial expressions. Such difficulties in empathy underlie their social-communication difficulties that form a core of the diagnosis. In this paper we ask whether aspects of empathy can be taught to young children with ASC. We review a study that evaluated The Transporters, an animated series designed to enhance emotion comprehension in children with ASC. Children with ASC (4–7 years old) watched The Transporters every day for four weeks. Participants were tested before and after intervention on emotional vocabulary and emotion recognition at three levels of generalization. The intervention group improved significantly more than a clinical control group on all task levels, performing comparably to typical controls at time 2. The discussion centres on how vehicles as mechanical systems may be one key reason why The Transporters caused the improved understanding and recognition of emotions in children with ASC. The implications for the design of autism-friendly interventions are also explored.  相似文献   
949.
950.
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