Conceptualizing Trust and Distrust as Alternative Stable States: Lessons from the Flint Water Crisis.

Despite the universally recognized importance of fostering trust and avoiding distrust in governance relationships, there remains considerable debate on core questions like the relation between (dis)trust and the evaluations of the characteristics that make a governance agent appear (un)worthy of trust. In particular, it remains unclear whether levels of (dis)trust simply follow levels of (dis)trustworthiness-such that building trust is primarily a question of increasing evidence of trustworthiness and avoiding evidence of distrustworthiness, or if their dynamics are more complicated. The current paper adds novel theory for thinking about the management of trust and distrust in the governance context through the application of principles borrowed from resilience theory. Specifically, we argue that trust and distrust exist as distinct, self-reinforcing (i.e., stable) states separated by a threshold. We then theorize as to the nature of the self-reinforcing processes and use qualitative data collected from and inductively coded in collaboration with Flint residents as part of a participatory process to look for evidence of our argument in a well-documented governance failure. We conclude by explaining how this novel perspective allows for clearer insight into the experience of this and other communities and speculate as to how it may help to better position governance actors to respond to future crises.

The influence of an enhanced recovery programme on clinical outcomes, costs and quality of life after surgery for colorectal cancer.

OBJECTIVE: Optimizing peri-operative care using an enhanced recovery programme improves short-term outcomes following colonic resection. This study compared a prospective group of patients undergoing resection of colorectal cancer within an enhanced recovery programme, with a prospectively studied historic cohort receiving conventional care. PATIENTS AND METHODS: Sixty patients underwent elective resection within an enhanced recovery programme (ERP). This incorporated pre-operative counselling, epidural analgesia, early feeding and mobilization. Clinical outcomes were compared with 86 prospectively studied historic control patients receiving conventional care (CC). All patients completed EORTC QLQ-C30, QLQ-CR38 and health economics questionnaires up to three months after surgery. RESULTS: Baseline clinical data were similar in both groups. Postoperative hospital stay was significantly reduced in the ERP, with patients staying 49% as long as those in the CC group including convalescent hospital stay (95% CI 39% to 61%P < 0.001). There were no differences in the number of complications, readmissions or re-operations. There were no significant differences in quality of life or health economic outcomes. CONCLUSION: Patients undergoing colorectal resection within an ERP stay in hospital half as long as those receiving conventional care, with no increased morbidity, deterioration in quality of life or increased cost.

Experiences with the shikimate-pathway enzymes as targets for rational drug design.

The background and current context of work on the shikimate-pathway enzymes as potential targets for anti-bacterial, anti-fungal and anti-parasitic drugs is reviewed. Recent work on the third enzyme of the pathway, dehydroquinase, which occurs in two structurally and mechanistically distinct forms, is used to illustrate the present state of studies into rational drug design.

Molecular thermodynamic model to predict the alpha-helical secondary structure of polypeptide chains in solution.

The native state of a protein molecule in aqueous solutions represents one of the lowest states of Gibbs energy [Anfinsen, C.B. (1973) Science 181, 223-230]. Much progress has been made about the rules of protein folding [King, J. (1989) Chem. Eng. News 67, 32-54] and the dominant forces in protein folding [Dill, K.A. (1990) Biochemistry 29, 7133-7155]. However, the quantitative contributions of different Gibbs energy terms to protein stability remains a controversial issue [Moult, J., & Unger, R. (1991) Biochemistry 30, 3816-3824]. A molecular thermodynamic model has been proposed for the Gibbs energy of folding a residue in aqueous homopolypeptides from a random-coiled state to either the alpha-helix state or the beta-sheet state [Chen, C.-C., Zhu, Y., King, J.A., & Evans, L.B. (1992) Biopolymers 32, 1375-1392]. In this work, we present a generalization of the molecular thermodynamic model for the Gibbs energy of folding natural and synthetic heteropolypeptides from random-coiled conformations into alpha-helical conformations. The generalized model incorporates the intrinsic folding potential due to residue-solvent interactions, the cooperative folding effect due to residue-residue interactions, and the location and length of alpha-helices. The utility of the model was demonstrated by examining the stability of alpha-helical conformations of a number of natural polypeptides including C-peptide (residues 1-13) and S-peptide (residues 1-20) of RNase A (bovine pancreatic ribonuclease A), the P alpha fragment in BPTI (bovine pancreatic trypsin inhibitor), and synthetic polypeptides (the copolymers of different amino acid residues) including alanine-based peptides (16 or 17 residues long) in water. The computed Gibbs energies correspond well with the experimental data on helicity. The results also accounted for the effects of amino acid substitution and temperature on the stability of alpha-helical conformations of the test polypeptides.

A molecular thermodynamic approach to predict the secondary structure of homopolypeptides in aqueous systems.

Under physiological conditions, many polypeptide chains spontaneously fold into discrete and tightly packed three-dimensional structures. The folded polypeptide chain conformation is believed to represent a minimum Gibbs energy of the system, governed by the weak interactions that operate between the amino acid residues and between the residues and the solvent. A semiempirical molecular thermodynamic model is proposed to represent the Gibbs energy of folding of aqueous homopolypeptide systems. The model takes into consideration both the entropy contribution and the enthalpy contribution of folding homopolypeptide chains in aqueous solutions. The entropy contribution is derived from the Flory-Huggins expression for the entropy of mixing. It accounts for the entropy loss in folding a random-coiled polypeptide chain into a specific polypeptide conformation. The enthalpy contribution is derived from a molecular segment-based Non-Random Two Liquid (NRTL) local composition model [H. Renon and J. M. Prausnitz (1968) AIChE J., Vol. 14, pp. 135-142; C.-C. Chen and L. B. Evans (1986) AIChE J., Vol. 32, pp. 444-454], which takes into consideration of the residue-residue, residue-solvent, and solvent-solvent binary physical interactions along with the local compositions of amino acid residues in aqueous homopolypeptides. The UNIFAC group contribution method [A. Fredenslund, R. L. Jones, and J. M. Prausnitz (1975) AIChE J., 21, 1086-1099; A. Fredenslund, J. Gmehling, and P. Rasmussen (1977) Vapor-Liquid Equilibrium Using UNIFAC, Elsevier Scientific Publishing Company, Amsterdam], developed originally to estimate the excess Gibbs energy of solutions of small molecules, was used to estimate the NRTL binary interaction parameters. The model yields a hydrophobicity scale for the 20 amino acid side chains, which compares favorably with established scales [Y. Nozaki and C. Tanford (1971) Journal of Biological Chemistry, Vol. 46, pp. 2211-2217; E. B. Leodidis and T. A. Hatton (1990) Journal of Physical Chemistry, Vol. 94, pp. 6411-6420]. In addition, the model generates qualitatively correct thermodynamic constants and it accurately predicts thermodynamically favorable folding of a number of aqueous homopolypeptides from random-coiled states into alpha-helices. The model further facilitates estimation of the Zimm-Bragg helix growth parameter s and the nucleation parameter sigma for amino acid residues [B. H. Zimm and J. K. Bragg (1959) Journal of Chemical Physics, Vol. 31, pp. 526-535]. The calculated values of the two parameters fall into the ranges suggested by Zimm and Bragg.

Representation of phase equilibrium behavior of antibiotics.

The phase equilibrium behavior of biomolecules is important both in understanding the partition mechanisms and in the design and optimization of downstream recovery processes. Chen et al. (1989) proposed a molecular thermodynamic framework that successfully represents the liquid-solid equilibrium behavior of amino acids and small peptides as functions of temperature, ionic strength, solvent compositions, and pH. Based on this theoretical framework, this paper presents recent results in representing the liquid-solid equilibrium behavior (solubilities) and the liquid-liquid equilibrium behavior (phase partitioning) of beta-lactam antibiotics, which are amino acid derivatives and important chemotherapeutic agents.

[Bursitis calcarea in a dog]. / Bursitis calcarea in 'n hond.

A case of bursitis calcarea in a Border Collie showing lameness without acute pain in the right hind leg, is reported. A diagnosis of bursitis calcarea was made on radiological examination. Treatment consisted of anti-inflammatory drugs and rest as far as it was practically possible. After initial improvement, full recovery only took place 2 months after treatment had commenced. Bursitis calcarea is a rare disease which seldom shows clinical signs. As far as could be ascertained, this is the first report of the condition in South Africa.

Factors affecting in vitro bond strength of no-mix orthodontic cements.

The effects of cement thickness and time of exposure of primer to a stimulated oral environment on tensile bond strength were determined in vitro for three no-mix cements and a two-paste cement. Five shims produced increasing cement thicknesses, and a humidor at 37 degrees C simulated an oral environment. SY had the greatest tensile bond strength (0.92 kg/mm2), whereas UN and ML had similar strengths (0.60 kg/mm2 and 0.66 kg/mm2, respectively), when no shims were used. Generally, there was a decrease in tensile bond strength as thickness increased for all no-mix cements. The failure site was essentially at the cement-base interface. Failures within the cement were characterized by incomplete polymerization of the resin. There was a decrease in tensile bond strength which ranged from 11% to 24% after primed teeth were stored in a simulated oral environment for 1.0 minute for ML and 2.5 minutes for UN and SY. This decrease in strength was accompanied by an increase in percentage failure at the paste-primer interface.

Osteosarcoma in a young Great Dane dog.

A 10-month-old Great Dane dog was presented showing lameness in the left foreleg. Radiographic examination revealed a severe bony reaction of the left distal radius and ulna. The reaction together with associated soft tissue swelling increased dramatically over a 6 week period. A diagnosis of osteogenic sarcoma was confirmed histologically and the dog was euthanased. Metastases were found post mortem in the left prescapular lymph node and left lung.

Clinical diagnosis of Spirocerca lupi infestation in dogs.

The clinical criteria used to establish a diagnosis of Spirocerca lupi infestation in dogs are discussed, with special emphasis on the radiographic feature that may be observed. Plain radiographs show a typical grey circumscribed area posterior to the heart. Following the administration of a barium meal this area takes on a dappled appearance due to barium accumulated in the crypts of the S. lupi granuloma. The granuloma itself may be outlined by the barium.

Fatal parasitism among free living bushbabies (galago crassicaudatus).

Four cases of severe parasitism due to Primasubulura otolicini in adult bush babies (Galago crassicaudatus) are described.

Surgical correction of premature closure of the ulnar growth plate in the dog.

Successful correction of anterior bowing of the foreleg and severe lateral carpal valgus following on premature closure of the ulnar growth plate in a month old Great Dane bitch is described. The procedure involved stapling the radius across the distal growth plate and section of the ulna.

Pathogenic leptospiras isolated from Malaysian surface waters.

Pathogenic leptospiras (1,424) isolated from natural waters and wet soils in Malaysia comprised 29 different serovars (synonym serotypes). All except two of the serovars had been found previously in Malaysia. The exceptional serovars were werrasingha, an Autumnalis serogroup member originally isolated in Ceylon, and a new serovar designated evansi. Serovar evansi had serological affinities with serovar ranarum which was isolated from the kidney of a frog in Iowa. The large variety of serovars found in jungle areas was consistent with similar previous findings of diverse serovar infections in troops who had operated in Malaysian jungles.

Failure of antrycide in treatment of leptospirosis in experimentally infected hamsters.

The chemotherapeutic efficacy of quinapyramine (antrycide) could not be demonstrated in hamsters experimentally infected with a virulent strain of serotype bataviae.

Deoxyribonucleic acid base composition and homology studies of Leptospira.

Four distinct genetic groups of leptospiras were demonstrated among selected pathogenic and "biflexa" serological types. Pathogenic leptospiras could be divided into two groups on the basis of per cent guanine + cytosine (GC) in their deoxyribonucleic acid (DNA). One group had 36 +/- 1%, the other 39 +/- 1%. The biflexa strains had DNA of 39 +/- 1% GC, but were further separated into two groups on the basis of DNA-annealing tests. Strains within groups had a high degree of specific duplex formation (75% binding or more with reference to the homologous DNA). There was little or no genetic relatedness between strains of the four groups (less than 10% DNA homology). The thermal elution midpoint of heterologous DNA duplexes was always lower than the homologous reaction. The serological relationships among strains were not meaningful in terms of relatedness determined by specific duplex formation.