SEARCH · PubMed Health

Results for “energy optimization”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,027 records · Page 57Linked to original sources

PubMed1983

Present practice of electroconvulsive therapy in Scandinavia.

We have set up guidelines for the practice of electroconvulsive therapy, based on Scandinavian clinical experience and research. Because the therapeutic effect is a result of the cerebral seizure, and the organic side effects partly consequences of the electrical stimulation, the aim should be to induce maximal seizure activity using minimal electrical energy. Essential features of optimal therapy are (1) absence of therapy with benzodiazepines and other anticonvulsant drugs, (2) superficial narcosis, (3) abundant oxygen supply, (4) threshold stimulation with brief-pulse stimuli, and (5) unilateral, parietotemporal, nondominant application of the electrodes. Seizure duration should always be measured to make sure that maximum seizure activity has taken place.

Depressive Disorder↗

PubMed2001

Energy substrate requirement for in vitro maturation of oocytes from unstimulated adult rhesus monkeys.

The energy substrates lactate, pyruvate, and glucose were evaluated for supporting in vitro cytoplasmic maturation of rhesus monkey oocytes. A total of 321 cumulus-oocyte complexes (COCs) aspirated from > or = 1000 microm diameter follicles of unstimulated adult monkeys were matured in one of six media with various individual or combinations of energy substrates: (1) mCMRL-1066 (control); (2) HECM-10 (containing 4.5 mM lactate); (3) HECM-10+0.2 mM pyruvate; (4) HECM-10 + 5.0 mM glucose; (5) HECM-10+ 0.2 mM pyruvate + 5.0 mM glucose; and (6) HECM-10 minus lactate + 5.0 mM glucose. All media contained gonadotropins, oestradiol, and progesterone. Following maturation, all mature oocytes were subjected to the same in vitro fertilization and embryo culture procedures. Oocytes matured in control medium or in treatment groups 4 and 6 had the best morulae+ blastocysts developmental responses (35, 36, and 32%, respectively, P < 0.05). HECM-10 + 0.2 mM pyruvate + 5.0 mM glucose for COC maturation supported intermediate embryonic development (16% morulae + blastocysts). The lowest (P < 0.05) morula + blastocyst developmental responses were obtained after maturation of COCs in HECM-t10 and HECM-10 + 0.2 mM pyruvate (4 and 6%, respectively). The COCs matured in glucose-containing medium showed greater levels of cumulus expansion than those in glucose-free medium. These results indicate that (a) glucose is both necessary and sufficient as the energy substrate for supporting optimal cytoplasmic maturation in vitro of oocytes from unstimulated rhesus monkeys; (b) pyruvate suppresses the stimulatory effect of glucose on oocyte maturation; (c) glucose is involved in cumulus expansion; (d) cumulus expansion is not a reliable indicator of primate oocyte competence.

Animals↗

PubMed1992

Randomized, controlled study evaluating effects of branched chain amino acids and alpha-ketoisocaproate on protein metabolism after surgery.

The effect of nutritional supplementation with branched chain amino acids or the ketoacid alpha-ketoisocaproate on protein metabolism after surgery was studied in 24 patients with gastrointestinal cancer. They were randomized to receive one of three nutritional regimens. All patients received a balanced amino acid solution and group 1 (n = 8) received no further supplements, group 2 (n = 8) received supplementation with alpha-ketoisocaproate (17 g day-1) and group 3 (n = 8) received a branched chain solution including leucine, isoleucine and valine, corresponding to 3.3 g nitrogen day-1. Plasma albumin, prealbumin, fibronectin and serum urea concentrations, nitrogen balance and 3-methylhistidine release from the leg and its excretion in the urine were measured. Albumin and prealbumin concentrations fell after surgery in all groups, and fibronectin levels fell in group 2 (P less than 0.001). In group 2 there was also a significant increase in serum urea concentration after operation (P less than 0.05). Cumulative nitrogen balance after 3 days was -5.6 g (group 1), -3.8 g (group 2) and -1.7 g (group 3). The release of 3-methylhistidine (nmol 100 g-1 min-1) from the leg after operation, following an overnight fast, was -0.42 (group 1), -0.51 (group 2) and -0.66 (group 3). During infusion the release was -0.56, -0.99 and -0.81, respectively. A balanced amino acid solution with an adequate energy supply has an optimal nitrogen-sparing effect. Branched chain amino acids or alpha-ketoisocaproate did not improve nitrogen balance or reduce protein degradation.

Amino Acids, Branched-Chain↗

PubMed1980

Design of an artificial skin. I. Basic design principles.

Individuals who suffer extensive loss of skin, commonly in fires, are acutely ill, in danger of succumbing either to massive infection of to severe fluid loss. Patients who survive these early threats must often cope with problems of rehabilitation arising from deep, disfiguring scars and crippling contractures. In this report we describe the physiocochemical, biochemical, and mechanical considerations that form the basis for two-stage design of a membrane useful as an experimental wound closure. Stage I of the design, applicable to short-term acute use, calls for a membrane which displaces efficiently air pockets from a carefully prepared woundbed, free of weak boundary layers, and maintains the moisture flux through the wound at an optimal level. Optimization of the surface energy, modulus of elasticity, energy to fracture and moisture permeability of the membrane are among the essential attributes of Stage I design. Stage 2 of the design, applicable to long-term, chronic use, focuses on a nonantigenic membrane which performs as a biodegradable template for synthesis of neodermal tissue. A survey of candidate materials suggests reasons for selection of a porous, crosslinked collagen-glycosaminoglycan coprecipitate as the chemical basis of an evolving design which was initiated 10 years ago. Over the past several years a set of membranes has been iteratively designed on this basis and has been used to cover satisfactorily large experimental full-thickness skin wounds in guinea pigs. Such membranes have effectively protected these wounds from infection and fluid loss for over 25 days without rejection and without requiring change or other invasive manipulation. When appropriately designed for the purpose, the membranes have also strongly retarded wound contraction and have become replaced by newly synthesized, stable connective tissue. Several rules relating the molecular structure and morphology of these membranes to cellular response of adjacent tissue have also been derived. This report is the first in a series which details the methodology of preparation and the record of performance.

Animals↗

PubMed2004

An AM1 semiempirical study of host-guest complexation in hemicarcerand complexes.

Semiempirical AM1 calculations have been carried out on host-guest complexes of model hemicarcerands 1a and 2a. The justification for the choice of the AM1 Hamiltonian was based on a comparison between reported X-ray data for the smaller tetrabromocavitand 4a and computational results obtained using several different Hamiltonians. The complexation behavior of hemicarcerands 1a and 2a have been compared with experimental results reported by Cram et al. for the related hemicarcerands 1b and 2b. Based on this comparison, a criterion for predicting guest encapsulation was developed, E(complexation), which relies on the calculation of AM1 heats of formation for host, guest, and hemicarceplex. If E(complexation) is lower than 10 kcal/mol, then a guest will be encapsulated, while if it is greater than 30 kcal/mol, a guest will not be encapsulated. The use of constrained-path AM1 optimizations to determine the energy barriers to guest entry and exit from the host was found to be a useful tool for examining suitable host-guest combinations when the E(complexation) criteria does not hold. We have computed the barriers to exit of N, N-dimethylformamide (dmf) and furan from the hemicarcerand 1a, the former has been compared with the experiment and shows excellent agreement. Based on the success of the above computational methods in predicting which host-guest combinations will form stable hemicarceplexes we have synthesized a new target hemicarceplex 1b.furan.

Journal Article↗

PubMed2006

A DFT study on the relative affinity for oxygen of the alpha and beta subunits of hemoglobin.

DFT calculations are carried out on computational models of the active center of the alpha and beta subunits of hemoglobin in both its oxygenated (R) and deoxygenated (T) states. The computational models are defined by the full heme group, including all porphyrin substituents, and the four amino acids closer to it. The role of the protein environment is introduced by freezing the position of the alpha carbon atom of each of the four amino acids to the positions they have in the available PDB structures. Oxygen affinity is then evaluated by computing the energy difference between the optimized structures of the oxygenated and deoxygenated forms of each model. The results indicate a higher affinity of the alpha subunits over the beta ones. Analysis of the computed structures points out to the strength of the hydrogen bond between the distal histidine and the oxygen molecule as a key factor in discriminating the different systems.

Computer Simulation↗

PubMed1980

Development of a carbon dioxide laser cystoscope.

CO2 laser lesions were created at varying power densities on the exteriorized canine bladders. A 50-watt carbon dioxide continuous laser coupled to a Zeiss surgical microscope was used. A schematic power curve was developed indexing depth of bladder penetration by the laser against laser energy output. Once the optimal power settings for the carbon dioxide laser were established, vertical heat transmission, hemostasis, and healing were studied. A prototype carbon dioxide laser cystoscope was then constructed that allowed endoscopic delivery of the CO2 laser beam into the intact canine bladder. The beam was focussed by a germanium lens and directed out the end of the endoscope, using a movable mirror. Eight dogs were then endoscopically studied in vivo.

Animals↗

PubMed2004

DFT and NMR parameterized conformation of valeranone.

A Monte Carlo random search using molecular mechanics, followed by geometry optimization of each minimum energy structure employing density functional theory (DFT) calculations at the B3LYP/6-31G* level and a Boltzmann analysis of the total energies, generated accurate molecular models which describe the conformational behavior of the antispasmodic bicyclic sesquiterpene valeranone (1). The theoretical H-C-C-H dihedral angles gave the corresponding 1H, 1H vicinal coupling constants using a generalized Karplus-type equation. In turn, the 3J(H,H) values were used as initial input data for the spectral simulation of 1, which after iteration provided an excellent correlation with the experimental 1H NMR spectrum. The calculated 3J(H,H) values closely predicted the experimental values, excepting the coupling constant between the axial hydrogen alpha to the carbonyl group and the equatorial hydrogen beta to the carbonyl group (J(2beta, 3beta)). The difference is explained in terms of the electron density distribution found in the highest occupied molecular orbital (HOMO) of 1. The simulated spectrum, together with 2D NMR experiments, allowed the total assignment of the 1H and 13C NMR spectra of 1.

Magnetic Resonance Spectroscopy↗

PubMed1995

De novo design of the hydrophobic cores of proteins.

We have developed and experimentally tested a novel computational approach for the de novo design of hydrophobic cores. A pair of computer programs has been written, the first of which creates a "custom" rotamer library for potential hydrophobic residues, based on the backbone structure of the protein of interest. The second program uses a genetic algorithm to globally optimize for a low energy core sequence and structure, using the custom rotamer library as input. Success of the programs in predicting the sequences of native proteins indicates that they should be effective tools for protein design. Using these programs, we have designed and engineered several variants of the phage 434 cro protein, containing five, seven, or eight sequence changes in the hydrophobic core. As controls, we have produced a variant consisting of a randomly generated core with six sequence changes but equal volume relative to the native core and a variant with a "minimalist" core containing predominantly leucine residues. Two of the designs, including one with eight core sequence changes, have thermal stabilities comparable to the native protein, whereas the third design and the minimalist protein are significantly destabilized. The randomly designed control is completely unfolded under equivalent conditions. These results suggest that rational de novo design of hydrophobic cores is feasible, and stress the importance of specific packing interactions for the stability of proteins. A surprising aspect of the results is that all of the variants display highly cooperative thermal denaturation curves and reasonably dispersed NMR spectra. This suggests that the non-core residues of a protein play a significant role in determining the uniqueness of the folded structure.

Amino Acid Sequence↗

PubMed1999

Theoretical evaluation of a model of the catalytic triads of serine and cysteine proteases by ab initio molecular orbital calculation.

Serine and cysteine proteases are structurally distinct families of proteolytic enzymes that exert analogous catalytic reactions. It is known that serine, histidine, and aspartate residues are involved in a putative catalytic triad of serine proteases whereas cysteine, histidine and aspartate (or asparagine) are involved in that of cysteine proteases. Although the overall three-dimensional structures of the two classes of proteases are quite different, a similar feature of the catalytic mechanism can be observed. We carried out a theoretical study in the gas phase on their two catalytic steps using ab initio molecular orbital calculation to evaluate the efficiency of each proteolytic activity. To examine the key aspects of the catalytic processes in their active sites, we employed simple molecular models, in which serine and histidine were substituted for by CH3OH and CH3SH, respectively, and aspartate by CH3CO2-. Molecular geometries of the two models were fully optimized by an energy-gradient method. The activation energies for proton transfer in the proteolytic steps and the total energies of each molecule in the intermediate states were calculated. These results revealed that the activation energy for proton transfer in the CH3SH-His-CH3CO2-system was smaller by 11 kcal mol-1than that of the CH3OH-His-CH3CO2-system. The calculated potential energy surface and the relative magnitudes of all steps in these reaction paths with regard to double proton transfer supported the above results. Taken together, these results indicated that the Cys-His-Asp proteolytic system might work more efficiently than the Ser-His Asp system.

Animals↗

PubMed1993

Treatment of leukemia with radiolabeled monoclonal antibodies.

In contrast to radioimmunotherapy of solid disease, wherein the primary obstacle to success is access of radiolabeled antibody to antigen-positive cells, in the treatment of leukemia delivering a lethal absorbed dose to the isolated cell appears to be the primary obstacle. The isolated cell is defined as one that is exposed only to self-irradiation (from internalized or surface-bound radiolabeled antibody) and to irradiation from free antibody in the blood. It is isolated in the sense that the particulate (beta, electron, alpha) emissions from its nearest neighboring antigen-positive cell do not contribute to its absorbed dose. Disease in the bone marrow and other tissues, since it is confined to a smaller volume, is more easily eradicated because the absorbed dose to a given cell nucleus is enhanced by emissions from adjacent cells (a smaller fraction of the emission energy is 'wasted'). The optimization simulations presented above for the M195 antibody suggest that the optimum dose of antibody that should be administered is that required to yield a concentration within the distribution volume of the antibody that is approximately equal to the concentration of antigen sites as determined by the tumor burden. Although not specifically considered in the modeling example presented above, antibody internalization and catabolism may be expected to play an important role in radioimmunotherapy treatment planning of leukemia. Depending upon the kinetics of internalization and catabolism, the absorbed dose to the red marrow and to antigen-positive cells may be reduced considerably, since catabolism, assuming that it is followed by rapid extrusion of the radioactive label, would decrease the cells' exposure time considerably. The recently demonstrated effectiveness of radioimmunotherapy in certain cases of B-cell lymphoma and in reducing tumor burden in acute myelogenous leukemia suggests that radioimmunotherapy is beginning to fulfill the promise held when it was initially conceived. The long delay in achieving reproducible success has, in large part, been the result of the conceptual simplicity of using agents that specifically 'target' tumor cells and they may thus selectively deliver cytotoxic agents. Emboldened by this apparent simplicity, early trials of radioimmunotherapy failed to consider the many variables involved in its implementation. As has been recently demonstrated using mathematical models of antibody delivery to solid tumor, chief among these may have been the failure to select the appropriate tumor type. By significantly reducing the problems associated with antibody delivery, hematopoietic malignancies offer the optimum conditions for successful radioimmunotherapy. As evinced by the wide range of antibody and radioactivity doses administered in the B-cell lymphoma trials, the case-specific nature of radioimmunotherapy requires an understanding of the relationship between the various input parameters and patient response. The complexity and interrelationship of these parameters precludes an experimental trial-and-error approach to their optimization. A stepwise approach to radioimmunotherapy treatment planning is proposed in which a model of antibody kinetics is developed and validated.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1993

A fast new approach to pharmacophore mapping and its application to dopaminergic and benzodiazepine agonists.

In the absence of a 3D structure of the target biomolecule, to propose the 3D requirements for a small molecule to exhibit a particular bioactivity, one must supply both a bioactive conformation and a superposition rule for every active compound. Our strategy identifies both simultaneously. We first generate and optimize all low-energy conformations by any suitable method. For each conformation we then use ALADDIN to calculate the location of points to be considered as part of the superposition. These points include atoms in the molecule and projections from the molecule to hydrogen-bond donors and acceptors or charged groups in the binding site. These positions and the relative energy of each conformation are the input to our new program DISCO. It uses a clique-detection method to find superpositions that contain at least one conformation of each molecule and user-specified numbers of point types and chirality. DISCO is fast; for example, it takes about 1 min CPU to propose pharmacophores from 21 conformations of seven molecules. We typically run DISCO several times to compare alternative pharmacophore maps. For D2 dopamine agonists DISCO shows that the newer 2-aminothiazoles fit the traditional pharmacophore. Using site points correctly identifies the bioactive enantiomers of indoles to compare with catechols whereas using only ligand points leads to selecting the inactive enantiomer for the pharmacophore map. In addition, DISCO reproduces pharmacophore maps of benzodiazepines in the literature and proposes subtle improvements. Our experience suggests that clique-detection methods will find many applications in computational chemistry and computer-assisted molecular design.

Algorithms↗

PubMed1995

Side-firing devices for laser prostatectomy. An overview.

Transurethral laser coagulation of the prostate has become an accepted treatment for benign prostatic hyperplasia (BPH). The most common method is the use of a sideward-firing fiber that, once inserted in the prostatic area, irradiates the abundant prostatic tissue with Nd:YAG laser light. In this study, eight different side-firing fibers that are commercially available were evaluated. The devices can be characterized by the way laser light is deflected sideward and by their thermal behavior. Most of the eight devices differ with regard to the angle at which the laser beam is deflected, the spot size on the irradiated tissue surface, and the heating of the device itself. Implementation of the optical and thermal characteristics of each device in the treatment protocol will contribute to the optimal use of laser energy for prostatectomy.

Equipment Design↗

PubMed1997

[Ultrasound coronary angioplasty: state of the art and new clinical aspects].

Therapeutic ultrasound was shown to ablate thrombi and to disrupt atherosclerotic plaques in vitro and recently to recanalize occluded coronary arteries in acute myocardial infarction (AMI). The goal of this article is to update collective experience and to weigh the promising and unresolved aspects of this newly developed technology and its clinical results. As therapeutic ultrasound was for long known a synonym for lithotripsy of calculi diseases, it lastly received high attention as a catheter-based ultrasound method to ablate thrombi and disrupt atherosclerotic plaques in interventional cardiology (Figure 1). The effect of therapeutic ultrasound to ablate selectively pathological tissue depends on its bioselectivity for elastic fibers: After ultrasound sonication, healthy tissue-rich in elastin and collagen-including arterial wall remains intact whereas thrombus and plaque with their minimal elastic support are found to be highly susceptible to ablation. Our catheter for coronary ultrasound thrombolysis (Figure 2) consists of a solid metal probe and is connected to a piezo-electric transducer at its proximal end. The distal part ends in a three-wire flexible segment with a 1.6 mm tip ball to guarantee maximal wire flexibility and optimal transmission of ultrasound energy. The initial in vitro studies resulted in a fundamental understanding of the destructive effect of ultrasound on tissue based on 4 factors: mechanical vibration, thermal effects, microcurrents, and cavitation. The first studies on human peripheral vessels were published in 1991 being performed during femoral bypass surgery on occluded and partially obstructed arteries. The procedure was performed without perforation, no adverse side effects emerged, restenosis rate was 20%. The clinical application of coronary ultrasound angioplasty was initiated in 1991; Siegel published his data on 44 patients. In his study, 30 patients with chronic atherosclerotic occlusive lesions and 14 with unstable or stable angina or AMI were treated by ultrasound angioplasty. Residual stenosis after ultrasound treatment was 71%, after balloon dilation reduced to 34%. In the 6-month follow-up angiograms showed no major adverse effect or restenosis. Our experience with coronary ultrasound thrombolysis (CUT) is based on the analysis of 33 patients' data in the feasibility (Table 1) plus multicenter phase of the ACUTE trial (Analysis of Coronary Ultrasound Thrombolysis Endpoints) (Figure 3). Our patients were exclusively treated for AMI by ultrasound angioplasty and afterwards by PTCA if required (Figure 4). The average final percent stenosis was 20% (Figure 5). The main efficacy parameters, device success and angiographic success rates were 100%, clinical success rate was 91.7% (Figure 6 and Table 2). The adverse clinical events of CUT are limited--at least in our studies--to reocclusion of infarct-related artery and ischemia and could be reversed by additional PTCA. No adverse clinical side effects were observed during sonication of the coronary tree. Final angiography revealed residual stenosis of 20% without morphological signs. These excellent results suggest that bioselectivity of ultrasound together with the developed skills of the catheter system induces rapid and selective thrombolysis with no need to cross the target lesion before sonication. But what is the better solution for thrombosis and which for plaque disruption? The development of transluminal balloon catheter really modified therapeutic approach to obstructive coronary and peripheral arterial disease but it is still accompanied by a high rate of abrupt closure, AMI and death. Although the use of intravenous thrombolytic agents is well established in the treatment of AMI and these agents are widely used, a large patient collective remains (up to 33% and more) in whom their use is inadvisable due to recent stroke, surgery, trauma or other contraindications. (ABSTRACT TRUNCATED)

Angioplasty↗

PubMed1999

[Oral nutrition therapy in malnutrition].

In the therapy of malnutrition in the elderly oral treatment should be preferred. It represents a particular challenge to relatives, caregivers and physicians. Because of the individual deficits in each patient a personal adapted plan has to be established. Treatment includes an optimized food supply, energy-rich and enriched meals, and liquid nutritional supplements but also special care during the meal and an inviting environment. The success is very much dependent on the intensity of care.

Aged↗

PubMed2005

Human topoisomerase I poisoning: docking protoberberines into a structure-based binding site model.

Using the X-ray crystal structure of the human topoisomerase I (top1) - DNA cleavable complex and the Sybyl software package, we have developed a general model for the ternary cleavable complex formed with four protoberberine alkaloids differing in the substitution on the terminal phenyl rings and covering a broad range of the top1-poisoning activities. This model has the drug intercalated with its planar chromophore between the -1 and +1 base pairs flanking the cleavage site, with the nonplanar portion pointing into the minor groove. The ternary complexes were geometry-optimized and relative interaction energies, computed by using the Tripos force field, were found to rank in correct order the biological potency of the compounds; in addition, the model is also consistent with the top1-poisoning inactivity of berberine, a major prototype of the protoberberine alkaloids. The model might serve as a rational basis for elaboration of the most active compound as a lead structure, in order to develop more potent top1 poisons as next generation anti-cancer drugs.

Berberine Alkaloids↗

PubMed1986

Studies on calcium binding to brush-border membranes from rabbit small intestine.

A study was made of the uptake of Ca2+ by brush-border membrane vesicles prepared from rabbit small intestine. The process was found to be time, temperature and substrate concentration dependent, displayed saturability, did not depend on added energy sources and occurred optimally in a pH range of 7.5-8.0. Although the transport of D-glucose by these membrane vesicles responded to changes in osmotic pressure as modified by adding cellobiose to the medium, the uptake of Ca2+ was found not to be osmotically-sensitive. Moreover, the equilibrium uptake value obtained when vesicles were exposed to 0.36 mM Ca2+ was some 60-fold higher than the amount that could have been accommodated by the intravesicular space, calculated from the equilibrium uptake of D-glucose. It was concluded from these results that the uptake involved complete binding of the Ca2+ to the membrane. The ionophore A23187 enhanced the rates of uptake and efflux of Ca2+ without affecting equilibrium values, which suggests that the binding of Ca2+ measured under our conditions was to interior sites of the membrane. The binding capacity was decreased in the presence of 10 mM lidocaine as indicated by a diminution of the equilibrium binding values. Generating an electrochemical potential (negative inside) by addition of valinomycin to vesicles pre-equilibrated with K2SO4, enhanced the rate of uptake of Ca2+. Addition of metal ions, on the other hand, inhibited the uptake, La3+ and Tb3+ being most effective followed by Mn2+, Ba2+ and Mg2+. Na+ and K+ were the least inhibitory. The properties of the Ca2+ uptake process found in rabbit brush-border membranes were compared to those of similar processes occurring in other species.

Adenosine Triphosphate↗

PubMed1988

Principles of selectivity of sodium and potassium binding sites of the Na+/K+-ATPase. A corollary hypothesis.

The mechanisms whereby the sodium and potassium binding sites of heart sacrolemmal Na+/K+-ATPase (EC 3.6.1.3) distinguished between monovalent cations were investigated using methods of enzyme kinetics. The properties of the sodium binding sites were studied in the presence of 2,4,6-trinitrobenzenesulfonic acid in concentrations completely inhibiting the action of potassium on the enzyme. To test the selectivity of potassium binding sites, K+-p-nitrophenylphosphatase activity was employed as a model. The results suggest that the selectivity of Na+- and K+-binding sites of Na+/K+-ATPase may be due to two independent mechanisms: (i) The principle of key and lock (formation of coordination bounds); (ii) Optimal difference between solvatation energy (in the specific binding site) and hydration enthalpy of the respective cation.

Animals↗