Barriers to protein folding: formation of buried polar interactions is a slow step in acquisition of structure.

In the MYL mutant of the Arc repressor dimer, sets of partially buried salt-bridge and hydrogen-bond interactions mediated by Arg-31, Glu-36, and Arg-40 in each subunit are replaced by hydrophobic interactions between Met-31, Tyr-36, and Leu-40. The MYL refolding/dimerization reaction differs from that of wild type in being 10- to 1250-fold faster, having an earlier transition state, and depending upon viscosity but not ionic strength. Formation of the wild-type salt bridges in a hydrophobic environment clearly imposes a kinetic barrier to folding, which can be lowered by high salt concentrations. The changes in the position of the transition state and viscosity dependence can be explained if denatured monomers interact to form a partially folded dimeric intermediate, which then continues folding to form the native dimer. The second step is postulated to be rate limiting for wild type. Replacing the salt bridge with hydrophobic interactions lowers this barrier for MYL. This makes the first kinetic barrier rate limiting for MYL refolding and creates a downhill free-energy landscape in which most molecules which reach the intermediate state continue to form native dimers.

Residue replacements of buried aspartyl and related residues in sensory rhodopsin I: D201N produces inverted phototaxis signals.

Residue replacements were made at five positions (Arg-73, Asp-76, Tyr-87, Asp-106, and Asp-201) in the Halobacterium salinarium phototaxis receptor sensory rhodopsin I (SR-I) by site-specific mutagenesis. The sites were chosen for their correspondence in position to residues of functional importance in the homologous light-driven proton pump bacteriorhodopsin found in the same organism. This work identifies a residue in SR-I shown to be of vital importance to its attractant signaling function: Asp-201. The effect of the substitution with the isosteric asparagine is to convert the normally attractant signal of orange light stimulation to a repellent signal. In contrast, similar neutral substitution of the four other ionizable residues near the photoactive site allows essentially normal attractant and repellent phototaxis signaling. Wild-type two-photon repellent signaling by the receptor is intact in the Asp-201 mutant, genetically separating the wild-type attractant and repellent signal generation processes. A possible explanation and implications of the inverted signaling are discussed. Results of neutral residue substitution for Asp-76 confirm our previous evidence that proton transfer reactions involving this residue are not important to phototaxis but that Asp-76 functions as the Schiff base proton acceptor in proton translocation by transducer-free SR-I.

Buried Truth

Important events often go untold or are a blur of headlines and thirty-second sound bites. Narrative nonfiction crime writing, however, explores societal flaws in depth and can lead to greater awareness of a litany of public issues. The genre sparks the senses, evokes emotion, and exposes the human condition. Nearly thirty years ago, the remains of four people were discovered in Colorado who had been murdered violently. One was a hard-working truck driver. The other three were transient men, each trying to eke out a meager existence. Their collective story is about how they suffered and lost, and it involves determined detectives, a ruthless killer and his family, and a judicial and interagency law-enforcement system that succeeded and also failed.

Heads buried in the sand: member states block solutions to the refugee crisis. EPC Commentary, 15 September 2015

Yesterday’s meeting of Interior Ministers demonstrated that the EU’s asylum and immigration policy remains incomplete. This is mainly due to the member states’ inability to plan ahead, their reluctance to adopt binding common rules – considered as a violation of their sovereignty – and their central position in the implementation of EU rules.

Near Real-Time Detection Of Pipe Bursts in Water Distribution Systems

The research work presented in the thesis describes a new methodology for the automated near real-time detection of pipe bursts in Water Distribution Systems (WDSs). The methodology analyses the pressure/flow data gathered by means of SCADA systems in order to extract useful informations that go beyond the simple and usual monitoring type activities and/or regulatory reporting , enabling the water company to proactively manage the WDSs sections. The work has an interdisciplinary nature covering AI techniques and WDSs management processes such as data collection, manipulation and analysis for event detection. Indeed, the methodology makes use of (i) Artificial Neural Network (ANN) for the short-term forecasting of future pressure/flow signal values and (ii) Rule-based Model for bursts detection at sensor and district level. The results of applying the new methodology to a District Metered Area in Emilia- Romagna’s region, Italy have also been reported in the thesis. The results gathered illustrate how the methodology is capable to detect the aforementioned failure events in fast and reliable manner. The methodology guarantees the water companies to save water, energy, money and therefore enhance them to achieve higher levels of operational efficiency, a compliance with the current regulations and, last but not least, an improvement of customer service.

Pipe Spring National Monument (N.M.), interim interpretive plan, second draft (1977) B1; Master plan (1978) B2; Development concept plan, environmental assessment (EA) B3; Statement for management (1981) B4; Record of decision, draft development concept plan and Finding of no significant impact (FONSI) (1982) : environmental impact statement.

Mode of access: Internet.

Blackfoot medicine-pipe ceremony.

Cover title.

Cast iron pipe /

Copy in Dept. of Rare Books and Special Collections bound in original black leather stamped in gold. P. 9-10 lacking.

Geohydrology of Pipe Spring National Monument area, northern Arizona /

Shipping list no.: 99-0209-P.

Pièce héroique, for pipe organ

Mode of access: Internet.

Pipe interaction with the backfill envelope.

"June 1999."