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Background: Hereditary angioedema (HAE) is a rare condition marked by swelling episodes in various body parts, including the extremities, upper airway, face, intestinal tract, and genitals. Long-term prophylaxis (LTP), prescribed to control recurring HAE attacks, is integral to its management. Previously, attenuated androgens (AAs) were the only oral LTP options. However, in 2020, berotralstat, an oral plasma kallikrein inhibitor, was approved in the United States. A 2018 survey of adults with HAE type I or type II showed that almost all the patients who used prophylactic HAE medication preferred oral treatment (98%) and felt that it fit their lifestyle better than injectable treatment (96%). Still, guidelines lack consensus on transitioning patients from AAs to alternative oral prophylactic therapy. Objective: This paper aims to share expert insights and patient feedback on transitioning from AAs to berotralstat, an alternative oral prophylactic therapy, from the perspective of clinicians with extensive experience in treating patients with HAE. Methods: A panel of five HAE specialists convened for a virtual half-day roundtable discussion in April 2023. Results: Discussions about transitioning from AAs to berotralstat were prompted by routine consultations, patient inquiries based on independent research, ineffective current treatment, or worsening AA-related adverse effects. For patients who switched from AAs, the physicians reported that the decision was influenced by the alternative therapy's ability to prevent HAE attacks, its safety, and the once-daily administration schedule. All expert panel members identified fewer AA-related adverse effects; better quality of life; and less severe, shorter, and less frequent HAE attacks as clinical or patient goals they hoped to achieve through the treatment switch. Conclusion: The emergence of new, highly specific LTP drugs for HAE calls for the development of comprehensive recommendations and guidelines for transitioning from AAs to alternative oral prophylactic therapy. The expert panel highlighted key factors to consider during the development of such guidelines. [ABSTRACT FROM AUTHOR]

The study of theory is often a daunting and uninviting, if not terrifying, introduction to sociology courses. Most students do not see theory as helpful intellectual hardware that can facilitate understanding, interpretation and construction of social knowledge. This is true not only in theory courses, but also in many sociology courses including introductory classes, Deviance, Race and Ethnicity, Gender, or Political Sociology in which instructors either address grand theories or teach area-specific theories. A theoretical framework is particularly necessary for sociology courses on deviance and criminology. Since many undergraduate students still tend to perceive crime and deviance as solely individualistic behaviors, an instructor must be able to clearly demonstrate how theory can be useful for understanding broader social causes and explanations of crime and deviance. In this paper, the authors describe an active learning technique, originally developed for a two-week intensive Sociology of Deviance course, that promotes enjoyable, stimulating, and applicable engagement with theory by combining a hypothetical case history with lecture, readings, and peer learning and teaching.

Working within a gender relations paradigm, the voluntary same-sex relationships of white, middle-class, middle-aged men are theorized to conform to two separate and distinct patterns; friendship and comradeship. Complicity with both the current manifestation of dominant masculinity as well as the underlying epistemological structure is seen to determine the interactional choices, friendship or comradeship, of men. A Web-based survey is used to gather data from a sample of the target population. Data are analyzed through exploratory and confirmatory factor analysis, multiple regression, and structural equation modeling. Statistical findings support the hypothesis that complicity with hegemonic masculinity tends to predict comradeship while resistance to hegemonic complicity predicts the practice of friendship. Keywords: gender relations paradigm, white/middle-class/middle-aged men, friendship, comradeship, hegemonic masculinity, hegemonic complicity, The voluntary, personal, nonsexual relationships of men with other men are one way in which men do gender (West & Zimmerman, 1987). These relationships, often mistakenly summarized as friendships, have [...]

The results of the research conducted on van der Waals complexes of aniline and 4-aminobenzonitrile with polar solvents formed in a supersonic jet is reported. It also reports the solvatochromism studies of all substituted benzenes and napthalenes.

Anthranilic acid undergoes a geometry changes between its ground and first-excited electronics states. Though both molecules possess a tramolecular hydrogen bond in their ground states, hydrogen bond in salicylic acid is stronger than in authranilic acid and the studies revealed that both systems exhibit similar behavior upon electronic excitation.

It has been possible to observe the wavelength-dependent photochemistry of trans-urocanic acid in the gas phase. Isomerization of trans-urocanic acid to cis-urocanic acid was seen to arise in the S1 electronic excited state.

The spectroscopy and intermolecular electronic energy transfer (EET) process for a series of molecules, 9-anthryl-(CH2)(subscript n) -- 1-naphthyl, n = 1, 3, and 6 (AnN), was researched in a supersonic jet. In the case of A3N and A6N, a face-to-face conformer can be formed in which exchange coupling can be effective in enhancing the EET rate and in A1N.

Laser ablation of Trp-Gly was investigated under the same experimental conditions formerly employed to successfully seed the fragile, nonvolatile dipeptide into a molecular beam. Results showed substantial fragmentation upon ablation. Helium entrainment may be needed to prevent decomposition. The measured angular distributions were extremely forward-peaked and bimodal. The velocity distributions were wider than a Boltzmann distribution and had no flow velocity.

Background: Long-term prophylaxis with subcutaneous C1-inhibitor (C1-INH[SC]; HAEGARDA, CSL Behring) in patients with hereditary angioedema (HAE) due to C1-INH deficiency (C1-INH-HAE) was evaluated in an open-label extension follow-up study to the international, double-blind, placebo-controlled COMPACT study. The current analysis evaluated patient-reported health-related quality of life (HRQoL) data from 126 patients in the open-label extension study randomized to treatment with C1-INH(SC) 40 IU/kg (n = 63) or 60 IU/kg (n = 63) twice weekly for 52 weeks. HRQoL was evaluated at the beginning of the open-label study and at various time points using the European Quality of Life-5 Dimensions Questionnaire (EQ-5D), the Hospital Anxiety and Depression Scale (HADS), the Work Productivity and Activity Impairment Questionnaire (WPAI), and the Treatment Satisfaction Questionnaire for Medication. The disease-specific Angioedema Quality of Life Questionnaire (AE-QoL) and HAE quality of life questionnaire (HAE-QoL) instruments were administered in a subset of patients. Statistical significance was determined by change-from-baseline 95% confidence intervals (CIs) excluding zero. No adjustment for multiplicity was done. Results: Mean baseline EQ-5D scores (Health State Value, 0.90; Visual Analog Scale, 81.32) were slightly higher (better) than United States population norms (0.825, 80.0, respectively) and mean HADS anxiety (5.48) and depression (2.88) scores were within "normal" range (0–7). Yet, patients using C1-INH(SC) 60 IU/kg demonstrated significant improvement from baseline to end-of-study on the EQ-5D Health State Value (mean change [95% CI], 0.07 [0.01, 0.12] and Visual Analog Scale (7.45 [3.29, 11.62]). In the C1-INH(SC) 60 IU/kg group, there were significant improvements in the HADS anxiety scale (mean change [95% CI], − 1.23 [− 2.08, − 0.38]), HADS depression scale (− 0.95 [− 1.57, − 0.34]), and WPAI-assessed presenteeism (mean change [95% CI], − 23.33% [− 34.86, − 11.81]), work productivity loss (− 26.68% [− 39.92, − 13.44]), and activity impairment (− 16.14% [− 26.36, − 5.91]). Clinically important improvements were achieved in ≥ 25% of patients for all domains except WPAI-assessed absenteeism (which was very low at baseline). Mean AE-QoL total score by visit ranged from 13.39 to 17.89 (scale 0–100; lower scores = less impairment). Mean HAE-QoL global scores at each visit (115.7–122.3) were close to the maximum (best) possible score of 135. Conclusions: Long-term C1-INH(SC) replacement therapy in patients with C1-INH-HAE leads to significant and sustained improvements in multiple measures of HRQoL. Trial registration A Study to Evaluate the Long-term Clinical Safety and Efficacy of Subcutaneously Administered C1-esterase Inhibitor in the Prevention of Hereditary Angioedema, NCT02316353. Registered December 12, 2014, https://clinicaltrials.gov/ct2/show/NCT02316353. [ABSTRACT FROM AUTHOR]

Background: Hereditary angioedema (HAE) due to C1 inhibitor (C1INH) deficiency is characterized by recurrent attacks of edema of the skin and mucosal tissues. Symptoms usually present during childhood (mean age at first attack, 10 years). Earlier symptom onset may predict a more severe disease course. Subcutaneous (SC) C1INH is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. We analyzed the long-term efficacy of C1INH (SC) in subjects ≤17 years old treated in an open-label extension (OLE) of the pivotal phase III Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1 Inhibitor Replacement Therapy (COMPACT) trial. Methods: Eligible subjects (age ≥6 years, with ≥4 attacks over 2 consecutive months before entry into the OLE or placebo-controlled COMPACT trial) were treated with C1INH (SC) 40 or 60 IU/kg twice weekly for 52–140 weeks. Subgroup analyses by age (≤17 vs. >17 years) were performed for key efficacy endpoints. Results: Ten subjects were ≤17 years old [mean (range) age, 13.3 (8–16) years, 3 subjects <12 years old; exposure range, 51–133 weeks]. All 10 pediatric subjects experienced ≥50% reduction (mean, 93%) in number of attacks versus the prestudy period, with a 97% reduction in the median number of attacks/month (0.11). All subjects had <1 attack/4-week period and 4 had <1 attack/year (1 subject was attack free). No subject discontinued treatment due to a treatment-related adverse event. Conclusions: Data from pediatric subjects treated with C1INH (SC) for up to 2.55 years and adult subjects revealed similar efficacy. C1INH (SC) is effective and well tolerated as long-term prophylaxis in children, adolescents, and adults with HAE. [ABSTRACT FROM AUTHOR]

Angle velocity distributions of 532 nm laser sputtered gold atoms were measured. No emission was observed at low fluence unless melt structure was first induced on the gold surface. After melting, the velocity distribution at 1.4 J/sq.cm. was Boltzmann at 6500 K and the angular distribution was cosine. At 4.9 J/sq.cm. the angle velocity distribution indicated collisional modification. These data contradicted thermal sputtering but may have resulted from surface plasmon excitation.

A study was conducted, using hydride stretch infrared spectroscopy, to probe the hydrogen atom dislocation in the excited electronic state. The result reveals direct evidence for electronic localization in the excited state.

The CaOH radical has been produced in a supersonic molecular beam by the reaction of water vapor with laser desorbed calcium. Three new electronic states, the D 2Σ+, E 2Σ+, and F states have been observed by laser induced fluorescence and resonance enhanced multiphoton ionization spectroscopy. The D and E states are linear, but the F state is bent, the first bent and strongly covalent state of CaOH to be observed. Vibrational constants for the D state have been determined and a partially rotationally resolved spectrum has provided the rotational constant and Ca–OH bond length in this state. The D and E states are more strongly bound than the ground state, perhaps indicating some covalent contribution to the bonding. Additional vibrational constants of the ground electronic state including the CaO–H vibrational frequency have been determined from the emission spectra. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The fluorescence spectra of a series of bichromophoric molecules consisting of covalently linked fluorene units were investigated in a supersonic jet. In three of the systems (spirobifluorene, d8h8-spirobifluorene and 1-methyl spirobifluorene) no electronic coupling and no corresponding exciton splitting were detected in the zero-point level of the S1 state. Only 9,9′-bifluorene exhibited an exciton splitting in the v=0 state. The lack of coupling was attributed to symmetry; in the spirobifluorenes the planes of the fluorene moieties and the S1←S0 transition moments are perpendicular. When low vibrational levels were excited, state mixing, and energy transfer between the chromophores was observed. This behavior is characteristic of the ‘‘small molecule’’ regime of radiationless transition theory. When higher vibrational levels were excited, the systems exhibited typical ‘‘large molecule’’ behavior. In this limit, both electronic energy transfer, as well as intramolecular vibrational relaxation contribute to the decay of the initially excited state. Intramolecular dispersive interactions were also investigated by comparing the bifluorenes with a series of reference compounds. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The low and high resolution fluorescence excitation spectra of d3-tryptamine have been observed in the environment of a cold, supersonic molecular beam. As in the case of h3-tryptamine, six bands due to the origins of different conformers have been found in the low resolution spectrum of deuterated tryptamine. A previous paper reported that conformers labeled A and B and conformers labeled D and E of tryptamine have identical rotational structures. However, for deuterated tryptamine those conformers have distinguishable rotational structures. Analysis of the rotational structure in the high resolution electronic spectra of five of the bands was used to determine the geometries of the different conformers. Conformers A, B, and F have a gauche conformation with respect to the rotation about the Cα–Cβ bond while conformers D and E have an eclipsed conformation. The geometries of conformers A and B and conformers D and E differ only in the orientation of the amino group. In these structures the angles of the internal rotation of the amino group are 180°, 60°, 180°, 60°, and -60° for conformers A,B, and D–F, respectively. Feature C consists of two overlapped conformers, and it is suggested that these conformers have the amino group trans to the indole ring. [ABSTRACT FROM AUTHOR]

We have observed the high resolution fluorescence excitation spectrum of the molecule tryptamine in the gas phase. At low resolution the spectrum contains six features which have been assigned as the origins of different conformers of the tryptamine molecule. At high resolution the rotational structure in each of these features has been resolved, and the rotational structure of five of the features has been analyzed. This analysis has provided information about the geometries of the different conformers. Two conformers, labeled A and F, have the amino group of the molecule gauche to the indole ring, while conformer D has the amino group nearly eclipsed by the indole ring. Conformer B has a rotational structure identical to that of conformer A, while the rotational structure of conformer E is identical to that of conformer D. It is suggested that the pairs of conformers with identical rotational structure are related to each other by rotation about the Cα–N bond, such a rotation moving only hydrogen atoms. Feature C consists of two overlapped conformers, and it is suggested that these conformers have the amino group trans to the indole ring. The direction of the transition moment is measured for five of the conformers and is found to be identical for all conformers within the precision of the measurement. The direction of the transition moment indicates that the transition is to the 1Lb excited electronic state. [ABSTRACT FROM AUTHOR]

The high resolution ultraviolet fluorescence excitation spectrum of indole in a supersonic jet has been measured. It was possible to resolve the rotational structure with an experimental resolution of 180 MHz. The details of the technique employed to achieve this resolution in the ultraviolet are described. Analysis of the high resolution spectrum yielded a transition moment direction which is compared to previous theoretical predictions. Application of high resolution spectroscopy to the problem of distinguishing the 1La and 1Lb electronic states in indole and indole derivatives is discussed. From the measured rotational constants possible geometries for the ground and excited states were also determined. [ABSTRACT FROM AUTHOR]

Studies the ultraviolet laser desorption of indole. Velocity distribution; Angular distribution; Absence of evidence of jet-like structure in the desorbed plume; Internal temperature of the different regions of the plume; Number of collisions per molecule occurring following desorption producing minor vibrational cooling.

We have studied a series of bichromophores of the form A-(CH2)n-D where A is a 9-anthryl group, D is either a N-methylanilino group or a N-methyl-p-methoxyanilino group, and n=1,2,3, or 4. The fluorescence excitation and emission spectra of these molecules have been observed in a supersonic jet and in a variety of solvents. In the gas phase, in the n=1 and n=3 molecules, and in an extended conformer of the n=4 molecules interactions are weak resulting only in a slightly redshifted anthracene spectrum. No redshifted emission was observed in these cases. For the n=2 molecules and a second conformer of the n=4 molecules we observed a redshifted emission in the gas phase. This emission is assigned as coming from a charge transfer (CT) state or exciplex. On the basis of the excitation and emission spectra we observed two different pathways to reach the CT state. For the molecules with donor N-methyl-N-alkylaniline, excitation took place to the locally excited (LE) state followed by relaxation to the CT state. For the molecules with donor N-methyl-N-alkyl-p-methoxyaniline, the CT state was low enough to interact with the ground state forming an intramolecular electron–donor–acceptor (EDA) complex. From this EDA ground state direct excitation to the CT state occurred. In the molecule with n=2 and donor N-methyl-p-methoxyaniline the EDA interaction is very weak allowing excitation to the LE state as well as to the CT state. This set of molecules exhibits the full range of spectroscopic behavior expected in bichromophores. [ABSTRACT FROM AUTHOR]

The one- and two-argon van der Waals complexes of dimethyl tetrazine (DMT) have been investigated by means of laser-induced excitation and dispersed fluorescence spectroscopy. The band shifts D‘0 - D’0 range from -23 to -31 cm-1 for DMT–Ar relative to DMT. The excited state dissociation energy of the DMT–Ar bond was estimated to be 270 ≤ D’0 ≤ 484 cm-1. In all levels with energy greater than the argon dissociation energy, predissociation is very fast. A dissociation rate constant kD = 3 × 109 s-1 has been determined for dissociation from the 6a1 level. This rate constant is an order of magnitude larger than that observed in tetrazine–argon. The dissociation rate constant of DMT–Ar2 from the 6a1 level is approximately 2 × 1010 s-1. Unlike aminotetrazine–Ar2, DMT–Ar2 shows no mode-selective variations in the branching ratios between the DMT and DMT–Ar photoproducts. [ABSTRACT FROM AUTHOR]

We have investigated the vibrational predissociation of argon complexes of 3-amino-s-tetrazine (AT) and 3-amino-6-methyl-s-tetrazine (AMT). Twelve vibrational levels of complexes of the form AT–Arn, where n=1, 2, and 3, were examined. The dissociation rate of the binary AT–Ar complex varied from 3×106 s-1 to >4×108 s-1 depending on the initially excited mode, with the fastest rate corresponding to the lowest energy vibration. Even levels with vibrational energies over five times that needed to break the van der Waals bond still showed significant amounts of fluorescence from the unfragmented complex. Photodissociation of the AT–Ar2 complex can yield two different dissociation products, AT and AT–Ar. The ratio of these photoproducts varied greatly among different vibrational modes. The 16b2 level of AT–Ar2 at +462 cm-1 gives primarily the AT photoproduct, while the 16a2 level at +505 cm-1 gives exclusively the AT–Ar photoproduct. The two levels of AT–Ar3 which were studied both appear to show only partial fragmentation. We examined the basic spectroscopy of AMT using vibrationally resolved fluorescence excitation spectroscopy, and assigned a number of vibrational levels in both the ground and excited states. We then used this information to measure the branching ratios and dissociation rates for seven vibrational levels of AMT–Ar. These vibrational predissociation rates show strong qualitative differences from similar data for tetrazine–Ar and aminotetrazine–Ar complexes. Finally, these results were compared to similar work on other tetrazine derivatives to attempt to account for this strong mode-selective behavior. [ABSTRACT FROM AUTHOR]

The photochemistry and photophysics of complexes of s-tetrazine (T) with acetylene have been studied in a supersonic free jet using laser induced fluorescence spectroscopy. Two complexes of the form T–C2H2 and a complex of the form T–(C2H2)2 were observed. One of the monoacetylene complexes has a stacked structure and one has a planar structure. In all cases low frequency vibrational structure was observed in the emission spectrum, and this allowed measurement of the frequencies of intermolecular vibrations. At some levels of excitation, all three complexes had broad features in their emission spectra. It was shown that in these cases, the density of states was sufficiently high that the molecular complexes were in the statistical limit, and therefore the broad structure was attributed to intramolecular vibrational relaxation (IVR). At higher levels of excitation, dissociation of the complexes was observed, and in some instances both IVR and dissociation were observed. Rate constants were measured by comparing the relative intensity of emission produced by these two decay channels with the intensity of resonance fluorescence. These rate constants were found to vary depending on the complex and upon the initially excited state of a given complex. When dissociation was observed, not all energetically allowed vibrational states were observed. The diacetylene complex was observed to dissociate to produce both monoacetylene complexes, but never the monomer. [ABSTRACT FROM AUTHOR]

Time-resolved measurements have been performed on seven vibronic levels of the S1 states of 3-amino-s-tetrazine (AT) and nine vibronic levels of 3-amino–6-methyl–s-tetrazine (AMT) ranging from 0 to 1907 cm-1 of excess vibrational energy. The resulting fluorescence lifetimes were found to range from 219 to 59 ns, and monotonically decreased with increasing excess energy. We have estimated the nonradiative rates and fluorescence quantum yields for these 16 levels by two different methods, which give reasonable agreement. These show that AT and AMT have nonradiative rates around 106–107 s-1, and very high fluorescence quantum yields, ranging from 0.07 to 0.29. This stands in contrast to s-tetrazine, which has a fluorescence lifetime of 800 ps, a nonradiative rate of 1.25×109s-1, and a fluoresence quantum yield of 0.000 94. This difference in the photophysical properties of AT and AMT relative to tetrazine is discussed in terms of the extensive work done on the photophysics and substituent effects of other azabenzenes, particularly pyridine. [ABSTRACT FROM AUTHOR]

The structure and spectroscopy of van der Waals clusters between argon and 3-amino-s-tetrazine (AT) has been investigated in a supersonic jet. Low resolution vibrationally resolved fluorescence excitation spectra of AT at a variety of argon gas concentrations enable us to assign the origin transitions for the clusters AT–Arn, where n=1 through 6. The frequencies of the van der Waals vibrational modes of these clusters are determined, both in the excited states from the excitation spectra, and in the ground state from single vibronic level emission spectra. High resolution spectroscopy is used to resolve rotational structure in the origin transitions of some of the clusters, and this provides structural information about the clusters. The argon atom in AT-Ar is found to be above the tetrazine ring, and the argon atoms in AT–Ar2 are found to be above and below the tetrazine ring, in all cases having a van der Waals bond length of about 3.3 Å. This work is useful in interpreting the results of our previous study on the photodissociation dynamics of van der Waals clusters between argon and AT. [ABSTRACT FROM AUTHOR]

Electronic excitation spectra of seven tryptophan derivatives entrained in a supersonic expansion have been recorded using both resonantly enhanced two-photon ionization and laser induced fluorescence. Two derivatives, tryptophan amide and tryptophan methyl amide, were found to have substantial low frequency vibrational progressions in their excitation spectra, yet in both compounds this behavior was apparent in only one conformer. Other derivatives did not display as much vibronic activity. Conformers which had vibrational progressions were found to emit in a broad band far to the red of excitation. All other conformers were found to fluoresce most strongly in resonance with excitation. The presence of low frequency vibrational activity and red shifted fluorescence correlates well with the ability of the derivative to form an intramolecular hydrogen bond between the amine and the carboxylic acid. Backbone conformers that contain an intramolecular hydrogen bond are expected to have large dipole moments, which may strongly perturb the electronic structure of the indole chromophore. [ABSTRACT FROM AUTHOR]

The isomerization of t-stilbene (stilbene h12 ) and three deuterated derivatives has been studied in a supersonic expansion, the thermal gas phase, and solution. In the jet we find that almost all effect of full deuteration (stilbene d12 ) is produced by deuteration of the two ethylinic hydrogens only (stilbene d2 ). Complete deuteration of the phenyl rings (stilbene d10 ) has rather little influence on the decay of the jet-cooled molecule. Nonexponential decays are found at intermediate excess energies in the jet-cooled system, with the degree of nonexponentiality decreasing with increasing excess energy. The ordering of the decay rates observed in the jet is not consistent with previous RRKM calculations of the isomerization rates of stilbene h12 and d2. Using similar parameters the calculations consistently place the stilbene d2 and stilbene d10 curves in the wrong order. Our results suggest extensive but not complete vibrational relaxation in the isolated molecule. Vibrational redistribution rapidly becomes complete in the presence of buffer gas. In thermal samples the isomerization rates of stilbene h12 and stilbene d10 are identical over a wide range of solvents and temperatures. By contrast the isomerization rates in stilbene d2 and stilbene d12 are 1.4 and 1.5 times slower than in stilbene h12. Again, these ratios appear constant over a wide range of experimental conditions. [ABSTRACT FROM AUTHOR]

Complexes between s-tetrazine and acetylene have been prepared in a supersonic free jet and their fluorescence excitation spectra have been observed. Analysis of the rotational structure in the electronic spectra of the complexes was used to determine the geometry of the complexes. Four bands due to complexes were observed at shifts of +15, +80, +201, and +208 cm-1 with respect to the origin of uncomplexed tetrazine at 18 128 cm-1. The bands at +15 and +80 cm-1 were assigned to two different isomers of a complex containing one molecule of tetrazine and one molecule of acetylene. The +15 band was due to a planar structure where the proton of acetylene forms a hydrogen bond with the nitrogen lone pair of tetrazine and the π cloud of the acetylene interacts with the hydrogen atom of the tetrazine ring. The +80 cm-1 band is due to a stacked complex with the acetylene molecule above and parallel to the plane of the tetrazine. In this isomer, the axis of the acetylene bisects the N–N bonds of the tetrazine. The band at 208 cm-1 is due to a complex consisting of two acetylene molecules and one tetrazine molecule with one acetylene above and parallel to the tetrazine ring and the other at the side of but perpendicular to the acetylene ring. The band at +201 cm-1 is assigned to a larger complex containing more than two acetylene molecules, but further analysis of this band was not possible. [ABSTRACT FROM AUTHOR]

The dispersed fluorescence of the amino acid tryptophan has been measured in the environment of a cold, supersonic free jet. Analysis of the region of the spectrum near the electronic origin indicates that the electronic excitation spectrum contains features which arise from various ground state conformers of tryptophan, confirming our previous assignment of these features. Under the conditions of our experiment the conformers do not interconvert in the excited state during the fluorescence liftime. Analysis of the dispersed emission spectrum of one conformer reveals broad red-shifted fluorescence which exists even when the electronic origin transition is excited. This broad red-shifted fluorescence is produced by the formation of an intramolecular exciplex involving excited state proton transfer to form a zwitterion. Molecules which do not have the ability to form a zwitterion do not exhibit this behavior, and deuterated trytophan shows broad fluorescence in an amount consistent with a slower proton transfer rate. The significance of these results for understanding the excited state photophysics of tryptophan in solution is discussed. [ABSTRACT FROM AUTHOR]