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At least 217 records · Page 12Linked to original sources
PubMed2002

Triplet births in the United States. An epidemic of high-risk pregnancies.

OBJECTIVE: To more precisely understand the changes in triplet births in recent years. STUDY DESIGN: Analysis of recent government and medical publications pertaining to triplets. RESULTS: Triplet births are at much greater risk than singletons of poor birth outcomes. More than 9 of 10 triplet births are born preterm (< 37 completed weeks of gestation) as compared with < 1 of 10 singleton infants. The average weight of a triplet newborn (1,698 g) is one-half that of a singleton newborn (3,358 g). The infant death rate for triplet and other higher-order multiple births is 12 times higher than that for singletons (93.7 as compared with 7.8 infant deaths per 1,000 live births). CONCLUSION: Based on their frequency of preterm birth, low birth weight and infant death rate, it is appropriate to characterize all triplet pregnancies as high risk.

Adult↗
PubMed2003

[Multifetal pregnancy reduction of triplets to twins: a prospective comparison of pregnancy outcome].

OBJECTIVE: To investigate the outcome of triplet pregnancy and the necessity and benefit of multifetal pregnancy reduction (MFPR). METHODS: Sixty cases of triplet pregnancy were collected. In 15 cases that did not choose MFPR, the triplets were spontaneously obtained. Out of the 45 cases with triplets obtained after infertility treatment, 32 chose reduction to obtain twins using transvaginal puncture of the fetal heart and physical hurt. The maternal obstetric complication rate, preterm delivery rate, means gestational age at delivery, birth weight of infants and percentage of fetal weights < 1,500 g were compared between these two groups. RESULTS: The maternal obstetric complication rate and preterm delivery rate were lower significantly in the reduction group. Deliveries occurred earlier slightly in the triplets group compared with the reduction group. The mean birth weight of infants was higher and the percentage of low weight infants (< 1,500 g) was lower in the reduction group. CONCLUSION: MFPR of triplets to twins is effective to improve pregnancy outcome. MFPR applied on triplets is reasonable and should be accepted if requested.

Adult↗
PubMed1992

[Triplets and quadruplets in Switzerland, 1985-1988].

To determine the incidence of multiple births and associated morbidity and mortality, we collected in a retrospective study all the multiple births (twins excluded) in Switzerland from 1985 to 1988. In all we followed 77 sets of triplets and 9 sets of quadruplets, representing an annual incidence of 1/3968 births for the triplets and 1/33,947 births for the quadruplets. The incidence of induced pregnancies increased in the period 1985 to 1988. The principal complications were premature contractions and preeclampsia. Only 56% of the children were born in a hospital with a neonatal intensive care unit. The mean gestational age was 33 0/7 weeks (ranging from 25 0/7 to 38 5/7) for the triplets, and 30 5/7 weeks (ranging from 27 5/7 to 36 3/7) for the quadruplets. The mean birthweight was 1787 g (ranging from 560 to 3000 g) for the triplets and 1189 g (ranging from 590 to 1980 g) for the quadruplets. RDS was found to be the principal neonatal pathology (65.5% of triplets and 85.2% of quadruplets) with 18.8% of triplets and 61.8% of quadruplets requiring ventilation. The mortality rate in our study was 8.9% for triplets and 14.7% for quadruplets.

Birth Weight↗
PubMed1991

[An analysis of cephalometric polygons in 21 sets of triplets].

Lateral cephalometric radiographs of 21 sets of triplets (4 monozygotic, 12 dizygotic and 5 three zygotic) were used for this study. The following two polygons were analysed: SNA and NSAr Go Me. Superimposition of the cephalometric tracings was made on the S-N line with S as the registration point. Intra- and inter-set comparisons between monozygotic (MZ), dizygotic (DZ) and three zygotic (TZ) triplets were made. Members of MZ triplets demonstrated the greatest similarity in size and form of the polygons. The second greatest similarity was found between MZ members of the DZ triplets, while the third DZ member of all such triplets showed much higher difference compared with the MZ members. Finally, triplets of TZ sets demonstrated the greatest difference between each other. The results obtained from this study indicated that genetic factors played a dominant role in growth and development of the craniofacial complex. However, difference found between members of MZ triplets suggested an importance of environmental factors in these processes as well.

Cephalometry↗
PubMed2006

The "non-reaction" of ground-state triplet carbon atoms with water revisited.

We introduce a novel experimental setup for the generation of carbon atoms by means of pulsed laser ablation with a pulse rate optimized to avoid warming of the matrix. The combination of this technique with annealing of the matrix, recooling, and spectral recording (e.g. IR) allowed us to differentiate between the reactivity of triplet and singlet carbon atoms towards water under matrix-isolation conditions. Our experimental procedure assures the relaxation of all unreacted carbon atoms to their triplet ground state in the 10 K matrix before spectral recording. In agreement with CCSD(T)/cc-pVTZ+ZPVE computational data and earlier lower level results, we find that triplet carbon atoms indeed do not react with water, despite their high initial energy. Intersystem crossing of the triplet to singlet states of hydroxy carbene are less important, as the barriers for rearrangement of the initial complex of triplet carbon atoms and water to covalently bound species are too high, and dissociation is more likely. We found no evidence for a direct O--H bond-insertion path for triplet carbon atoms. Self-condensation reactions of triplet carbon atoms are clearly favored and yield carbon clusters that show reactivity of their own. The proposed formation of aldoses in extraterrestrial environments can therefore only derive from "hot" carbon atoms or through photoreactions.

Journal Article↗
PubMed1999

Taxon-specific content of oligonucleotide triplets in 16S rRNAs of anoxygenic phototrophic and nitrifying bacteria.

Theoretical evaluation of the content of oligonucleotide triplets AAA, CCC, and UAU in 16S rRNAs of anoxygenic phototrophic bacteria (genera Chlorobium; Chloroflexus; Chromatium: Rhodopseudomonas) and nitrifying bacteria (genera Nitrosococcus, Nitrosomonas, Nitrosolobus, Nitrosovibrio, Nitrospira, Nitrospina, Nitrobacter) showed that the number of the AAA, CCC or UAU triplets in 16S rRNAs specifically corresponds to the genus and species of bacteria. The ratio of AAA and CCC triplet numbers in the sequences of 16S rRNA (AAA/CCC) of anoxygenic phototrophic bacteria was within the range of 0.61 to 2.03, and the ratio of AAA and UAU (AAA/UAU) triplet numbers in the sequence of 16S rRNA was within the range of 2.88 to 12.00. The regions of any genus within the AAA/CCC and AAA/UAU axes did not overlap. The combination of the numbers of nucleotide triplets in 16S rRNA is genus-specific character. The similar data were obtained in the study of a physiological group of nitrifying bacteria. The range of AAA/UAU ratio was from 1.8 to 9.0, and range of AAA/CCC was from 0.9 to 2.6 for this taxon. The number of triplets in 16S rRNAs of the studied taxa was genus- and species-specific character. The biological significance of these data is the evidence that not only the sequence but the number of nucleotide triplets in 16S rRNAs reflects the phylogeny of corresponding taxa.

Bacteria↗
PubMed1991

Neurofilament protein triplet immunoreactivity in the dorsal root ganglia of the guinea-pig.

Immunoreactivity for the neurofilament protein triplet was investigated in neurons of the dorsal root ganglia of the guinea-pig by using a battery of antibodies. In unfixed tissue, nearly all neurons in these ganglia demonstrated some degree of neurofilament protein triplet immunoreactivity. Large neurons generally displayed intense immunoreactivity, whereas most small to medium-sized neurons showed faint to moderate immunoreactivity. Double-labelling immunofluorescence demonstrated that most antibodies to the individual subunits of the neurofilament protein triplet had the same distribution and intensity of labelling in sensory neurons. Increasing durations of tissue fixation in aldehyde solutions selectively diminished neurofilament protein triplet immunoreactivity in small to medium-sized neurons. Double-labelling with neurofilament protein triplet antibodies in combination with antibodies to other neuronal markers, such as neuron-specific enolase, substance P and tyrosine hydroxylase, showed that tissue processing conditions affect the degree of co-localization of immunoreactivity to the neurofilament protein triplet and to these other neuronal markers. These results indicate that, with a judicious manipulation of the duration of tissue fixation, neurofilament protein triplet immunoreactivity can be used in combination with other neuronal markers to distinguish groups of neurons according to their size and chemical coding.

Animals↗
PubMed1992

The neurofilament triplet is present in distinct subpopulations of neurons in the central nervous system of the guinea-pig.

It is commonly assumed that most, if not all, neurons contain the intermediate filament protein class known as the neurofilament protein-triplet. The following study investigated the distribution of neurofilament protein-triplet immunoreactivity in selected regions of the guinea-pig central nervous system using monoclonal antibodies directed against phosphorylation-independent epitopes on the three subunits under optimal tissue processing conditions. Neurofilament protein-triplet immunoreactivity was present in distinct subpopulations of neurons in the cerebellar cortex, neocortex, hippocampal formation, retina, striatum and medulla oblongata. In many of these regions, labelled neurons represented only a small proportion of the total. The selective distribution of this intermediate filament protein class was confirmed in double-labelling experiments using antibodies to the neurofilament protein-triplet in combination with antibodies to other neuronal markers. The distribution of neurofilament protein-triplet immunoreactivity also correlated with the distribution of staining observed with a silver impregnation method based on Bielschowsky. The present results in combination with previous observations have demonstrated that the neurofilament protein-triplet is found in specific subclasses of neurons in different regions of the nervous system. Content of this intermediate filament protein class does not appear to be correlated with neuronal size or length of projection. These results also suggest that the selectivity of staining between neuronal classes observed with classical silver impregnation methods may be due to the presence or absence of the neurofilament protein-triplet. The present results may also provide a new perspective on the basis of the selective vulnerability of neurons in degenerative diseases.

Animals↗
PubMedDate not supplied

Complementary immunohistochemical distribution of the neurofilament triplet and novel intermediate filament proteins in the autonomic and sensory nervous system of the guinea-pig.

We have previously established that immunoreactivity for the triplet of polypeptides that comprise the class IV intermediate filament proteins (NFP-triplet) is localized in specific subpopulations of neurons in guinea-pig sensory and autonomic ganglia. Antibodies to novel neurofilament proteins, including a polyclonal antibody to a 57 kDa neuronal intermediate filament polypeptide (NIF57kD) and a monoclonal antibody (CH1) to a 150 kDa intermediate filament, or associated, protein were used in combination with antibodies to the NFP-triplet for double-labelling immunohistochemistry. The results show that different subpopulations of neurons in the guinea-pig dorsal root ganglia, coeliac ganglion and enteric ganglia can be distinguished by their complementary immunoreactivity for these proteins. In dorsal root ganglia, larger neurons are intensely immunoreactive for the NFP-triplet while immunoreactivity with CH1 and NIF57kD antibodies is restricted to the small to medium-sized neurons. In the coeliac ganglion, two regionally defined subpopulations of neurons can be distinguished by their immunoreactivity for either the NFP-triplet or NIF57kD, whereas CH1 labels all neurons with equal intensity. Three classes of morphologically distinct myenteric neuron subpopulations are also distinguished by their immunoreactivity for either the NFP-triplet, NIF57kD or CH1 antibodies. Two classes of submucous neurons are labelled both with CH1 and NIF57kD antibodies but show faint or no immunoreactivity for the NFP-triplet. It is concluded that intermediate filament protein immunoreactivity marks different subpopulations of neurons, which suggests that these proteins may have specific roles in neuronal function.

Animals↗
PubMedDate not supplied

Humoral sensitization against rejected grafts: specific antibodies to graft immunogenic amino acid triplets.

Humoral sensitization against immunogenic amino acid (aa) triplets expressed on a rejected graft was analyzed in 83 retransplant candidates. All patients had lost a graft with HLA-A,-B mismatches. The alloantibodies were detected by a complement-dependent cytotoxicity (CDC) technique and an ELISA method in parallel; they were classified as HLA graft-specific (GS) and non-GS antibodies. The aa triplet specificity of the antibodies was assessed using the HLAMatchmaker algorithm. HLA class I antibodies were detected in 74 of 78 (94%) cases, including GS reactivity in 55 (74.3%) and non-GS in 72 (97.2%), either alone (n = 19) or in parallel with GS antibodies (n = 53). For all HLA-GS-antibody-reactive patients, we defined the specificity against immunogenic aa triplets on the previous graft. Moreover, antibodies specific to graft aa triplets were observed within the non-GS antibodies among 19 of 19 and 28 of 53 cases, respectively. Therefore, aa triplet-specific antibodies against the rejected graft were present in all 74 cases with HLA class I antibodies. Antibodies against aa triplets expressed on all HLA class I-mismatched graft antigens were present in 73% of cases. The high extent of humoral alloreactivity against a rejected graft supports the decision to avoid repeated exposure to immunogenic aa triplet mismatches on a second graft. An accurate analysis for performed antibodies in these cases may be beneficial to select the most suitable second donor.

Antibody Formation↗
PubMed1995

Triplet and fluorescing states of the CP47 antenna complex of photosystem II studied as a function of temperature.

Fluorescence emission and triplet-minus-singlet (T-S) absorption difference spectra of the CP47 core antenna complex of photosystem II were measured as a function of temperature and compared to those of chlorophyll a in Triton X-100. Two spectral species were found in the chlorophyll T-S spectra of CP47, which may arise from a difference in ligation of the pigments or from an additional hydrogen bond, similar to what has been found for Chl molecules in a variety of solvents. The T-S spectra show that the lowest lying state in CP47 is at approximately 685 nm and gives rise to fluorescence at 690 nm at 4 K. The fluorescence quantum yield is 0.11 +/- 0.03 at 4 K, the chlorophyll triplet yield is 0.16 +/- 0.03. Carotenoid triplets are formed efficiently at 4 K through triplet transfer from chlorophyll with a yield of 0.15 +/- 0.02. The major decay channel of the lowest excited state in CP47 is internal conversion, with a quantum yield of about 0.58. Increase of the temperature results in a broadening and blue shift of the spectra due to the equilibration of the excitation over the antenna pigments. Upon increasing the temperature, a decrease of the fluorescence and triplet yields is observed to, at 270 K, a value of about 55% of the low temperature value. This decrease is significantly larger than of chlorophyll a in Triton X-100. Although the coupling to low-frequency phonon or vibration modes of the pigments is probably intermediate in CP47, the temperature dependence of the triplet and fluorescence quantum yield can be modeled using the energy gap law in the strong coupling limit of Englman and Jortner (1970. J. Mol. Phys. 18:145-164) for non-radiative decays. This yields for CP47 an average frequency of the promoting/accepting modes of 350 cm-1 with an activation energy of 650 cm-1 for internal conversion and activationless intersystem crossing to the triplet state through a promoting mode with a frequency of 180 cm-1. For chlorophyll a in Triton X-100 the average frequency of the promoting modes for non-radiative decay is very similar, but the activation energy (300 cm-1) is significantly smaller.

Biophysical Phenomena↗
PubMed1998

The outcome of abdominally delivered triplets and twins: a matched case-control study.

OBJECTIVE: To compare the outcome of matched triplets and twins delivered by cesarean section by order of delivery. STUDY DESIGN: 39 sets of triplets delivered abdominally were matched to 39 sets of twins also delivered by cesarean section in the same gestational age. The newborns outcome according to their birth order was analyzed. RESULTS: The mortality rate of triplets was twice than that of matched twins. While first born triplets had mortality rates similar to the first and second twins, there was a threefold increase in mortality rates of the second and third triplets as compared to the first triplet or twin. CONCLUSIONS: Triplets have a poorer outcome than twins even when they are delivered abdominally at the same gestational age. These differences are particularly noted in the second and third newborns.

Case-Control Studies↗
PubMed2002

Examining the potential role of DNA polymerases eta and zeta in triplet repeat instability in yeast.

Triplet repeats undergo frequent mutations in human families afflicted with certain neurodegenerative diseases and also in model organisms. Although the molecular mechanisms of triplet repeat instability are still being identified, it is likely that aberrant DNA synthesis plays an important role. Many DNA polymerases stall at triplet repeat sequences, probably due to the adoption of unusual DNA secondary structures. One possible mechanism to explain triplet repeat contractions is that a triplet repeat hairpin on the template strand inhibits replicative polymerases and that one or more bypass polymerases are recruited for synthesis past the hairpin. If the translesion synthesis is mutagenic, contractions can be generated. To address this possibility, Saccharomyces cerevisiae strains lacking either pol zeta (rev7), pol eta (rad30), or both were tested for trinucleotide repeat (TNR) contractions using three separate, sensitive genetic assays. If these bypass polymerases are important for mutagenesis, then the mutants should show a reduction in the contraction rate. Two genetic tests for triplet repeat contractions showed no significant change for the mutants compared to wild type. A third assay showed a five-fold reduction in contraction rates due to pol eta ablation. Despite this modest decrease, the overall contraction rate was still high, indicating that many deletions still occur in the absence of both polymerases. Expansion rates were also unaffected in the mutant strains. These results indicate that, in yeast, pol eta and pol zeta most likely have little role in triplet repeat mutagenesis.

DNA Replication↗
PubMed1992

Structure of a G.T.A triplet in an intramolecular DNA triplex.

A 32-base DNA oligonucleotide has been studied by one- and two-dimensional 1H NMR spectroscopy and is shown to form a stable, pyr.pur.pyr, intramolecular triple helical structure, with a four C loop and a TATA loop connecting the Watson-Crick- and Hoogsteen-paired strands, respectively. This triplex contains five T.A.T base triplets, two C+.G.C base triplets, and an unusual G.T.A base triplet which disrupts the pyr.pur.pyr motif. The G.T.A triplet consists of a Watson-Crick T.A base pair, with the T situated in the "purine strand" and the A situated in the "pyrimidine strand" and a G situated in the Hoogsteen-base-paired "pyrimidine strand" hydrogen bonded to the T. The base-pairing structure of the G.T.A triplet has been investigated and has been found to involve a single hydrogen bond from the guanine amino group to the O4 carbonyl of the thymine, leaving the guanine imino proton free. The specific amino proton involved in the hydrogen bond is the H2(2) proton. This orients the guanine such that its sugar is near the thymine methyl group. The guanine sugar adopts an N-type (C3'-endo) sugar pucker in this triplet. The stability of the G.T.A triplet within pyr.pur.pyr triplexes is discussed.

Base Composition↗
PubMed1994

T.C.G triplet in an antiparallel purine.purine.pyrimidine DNA triplex. Conformational studies by NMR.

The antiparallel purine.purine.pyrimidine DNA triplex, RRY6, which contains a T.C.G inverted triplet in the center of the sequence, was examined by proton and phosphorous two-dimensional NMR spectroscopy. The local conformation of the T.C.G triplet (T4.C11.G18) and the effect of this triplet on the global helical structure were analyzed in detail. The formation of the T.C.G triplet is confirmed by a set of cross-strand NOEs, including unusual cross-strand NOEs between the third strand and the pyrimidine strand as opposed to the purine strand of the duplex. NMR data suggest that the T.C.G triplet may be present in an equilibrium between a non-hydrogen-bonded form and a T(O4)-C(NH2) hydrogen-bonded form and that there is a distortion of the in-plane alignment of the three bases. The flanking G.G.C base triplets are well-defined on the 5'-side of T4, but somewhat interrupted on the 3'-side of T4. The effect of the third strand binding on the Watson-Crick duplex was probed by an NMR study of the free duplex RY6. NMR parameters are affected mostly around the T.C.G inversion site. The perturbations extend to at least two adjacent base triplets on either side. The binding of the third purine strand and the accommodation of a central T.C.G inversion in RRY6 does not require a readjustment in sugar pucker, which remains in the range of C2'-endo. 31P resonances of RRY6 distribute over a range of 2.2 ppm. The H-P coupling patterns of the third strand differ from those of the duplex. General spectral patterns defined by the marker protons of the RRY and YRY triplexes are compared.

Base Sequence↗
PubMed2001

Triplet formation on a monomeric chlorophyll in the photosystem II reaction center as studied by time-resolved infrared spectroscopy.

The process of formation of the triplet state of chlorophyll in the photosystem II (PS II) reaction center complex was studied by means of time-resolved infrared (IR) spectroscopy. Using a dispersive-type IR spectrometer with a time resolution of approximately 55 ns, transient spectra in the C=O stretching region (1760--1600 cm(-1)) were measured at 77 K. The data were analyzed by singular-value decomposition and subsequent least-squares fitting. Two distinct spectral components having different kinetic behaviors were resolved. One had spectral features characterized by negative peaks at 1740 and 1680 cm(-1) and an overall positive background and was assigned to the P(680)(+)Phe(-)/P(680)Phe radical pair by static FTIR measurements of the P(680)(+)/P(680) and Phe(-)/Phe differences. The other had prominent negative and positive peaks at 1668 and 1628 cm(-1), respectively, which were previously assigned to the keto C==O change upon triplet formation of the monomeric chlorophyll denoted as Chl(T) [Noguchi, T., Tomo, T., and Inoue, Y. (1998) Biochemistry 37, 13614-13625]. The former component of P(680)(+)Phe(-)/P(680)Phe exhibited a multiphasic decay with time constants of 77 ns (75%), 640 ns (18%), 8.3 micros (4%), and 0.3 ms (3%), while the latter component of (3)Chl(T)/Chl(T) was formed with a single-exponential rise with a time constant of 57 ns and had a lifetime of 1.5 ms. From the observations that only the two spectral components were resolved without any other triplet intermediates and the time constant of (3)Chl(T) formation roughly agreed with or seemed even faster than that of the major phase of the P(680)(+)Phe(-) decay, two alternative mechanisms of triplet formation are proposed. (i) (3)Chl(T) is directly formed from P(680)(+)Phe(-) by charge recombination at Chl(T), and (ii) (3)P(680) is formed, and then the triplet is transferred to Chl(T) with a time constant of much less than 50 ns. The location of Chl(T) in the D1 subunit as the monomer chlorophyll corresponding to the accessory bacteriochlorophyll in the L subunit of purple bacteria is favored to explain the former mechanism as well as the triplet properties reported in the literature. The physiological role of the triplet formation on Chl(T) is also discussed.

Chlorophyll↗
PubMed2006

Aqueous oxidation of phenylurea herbicides by triplet aromatic ketones.

Excited triplet states of dissolved natural organic matter (DOM) are important players for the transformation of organic chemical contaminants in sunlit natural waters. The present study focuses on kinetics and mechanistic aspects of the transformation of phenylurea herbicides induced by well-defined excited triplet states, which have been chosen to model DOM triplet states having oxidative character. The aromatic ketones benzophenone, 3'-methoxyacetophenone, and 2-acetonaphthone were used to photogenerate their triplet states and oxidize a series of eleven substituted phenylureas. Quenching of the excited triplet states by the phenylureas was measured using laser flash photolysis in the microsecond time domain, while the oxidation kinetics of the phenylureas was followed under steady-state irradiation. Second-order rate constants for quenching and oxidation were largely identical for a given pair of ketone and phenylurea. They reached the diffusion-controlled limit (approximately 4 x 10(9) M(-1) s(-1)) and decreased with increasing free energy of electron transfer from the phenylurea to the ketone triplet. These results confirm those already obtained using phenols as the substrates to be oxidized and suggest that oxidation rates are mainly determined by the bimolecular rate constant for electron transfer, a rule that can possibly be extended to various organic contaminants. A refined estimate of the effective reduction potential of DOM excited triplet states was also obtained.

Chemistry↗
PubMed2001

The almost bottleable triplet carbene: 2,6-dibromo-4-tert-butyl-2',6'-bis(trifluoromethyl)-4'-isopropyldiphenylcarbene.

Computations on 2,6-dibromo-4-tert-butyl-2',6'-bis(trifluoromethyl)-4'-isopropyldiphenylcarbene (1) using ab initio and density functional theory methods underscore the unusual stability of the triplet over the singlet state. At the B3LYP/6-311G(d,p) level, the triplet state had a slightly bent central C-C-C bond angle of 167 degrees, whereas this angle in the singlet was 134 degrees. The B3LYP singlet-triplet splitting (12.2 kcal/mol) was larger than that of the parent molecule (5.8 kcal/mol), diphenylcarbene (2), which also has a triplet ground state. The energy of a suitable isodesmic reaction showed the triplet and singlet states of (1) to be destabilized, by 6.3 and 12.5 kcal/mol, respectively, due to the combined effects of the CF3, Br, and alkyl substituents. The linear-coplanar form of (3)(1), which might facilitate dimerization or electrophilic attack at the more exposed diradical center, was prohibitively (35.9 kcal/mol) higher in energy. Our results confirm Tomioka's conclusion that the triplet diarylcarbene, ortho-substituted with bulky CF3 and Br substituents, is persistent due to steric protection of the diradical center. Dimerization and other possible reaction pathways are inhibited, not only by the bulky ortho substituents but also by the para alkyl groups. The increase in stability of the triplet ((3)(1)) state relative to the singlet ((1)(1)) state does not influence the reactivity directly.

Journal Article↗