Sensory innervation of the external and internal genitalia of the female rat

Using a whole-nerve recording method, the genitalia of the female rat were found to receive afferent innervation as follows. Pelvic nerve: vagina, cervix, and perineal skin; hypogastric nerve: cervix and proximal three fifths of the uterus; pudendal nerve: skin of perineum, inner thigh, and clitoral sheath. It is probable that the pudendal and pelvic nerves are activated during copulation, and that all 3 nerves are activated during parturition

Synthesis and Structure of Li[(C_5H_4)CH_2CH_2(TACN-^iPr_2)]. A Lithium Complex Supported by a Cp/TACN-^iPr_2 Ligand

The new ligand (C_5H_5)CH_2CH_2(TACN-^iPr_2) (TACN-^iPr_2 = 4,7-diisopropyl-1,4,7-triaza-1-cyclononyl) has been prepared and structurally characterized as its lithium complex, Li[(C_5H_4)CH_2CH_2(TACN-^iPr_2)]. The method of preparation employed nucleophilic addition of the lithium amide complex [Li(TACN-^iPr_2)]_2 to spiro[2.4]hepta-4,6-diene. The crystal structure of [Li(TACN-^iPr_2)]_2 is also presented

High-spin and low-spin iron(II) complexes with facially-coordinated borohydride ligands

Rare examples of monometallic high-spin and low-spin L_3Fe(H_3BH) complexes have been characterized, where the two L_3 ligands are [Tp^(Ph2)] and [PhBP3] ([Tp^(Ph2)] = [HB(3,5-Ph_2pz)_3]− and [PhBP_3] = [PhB(CH_2PPh_2)_3]−). The structures are reported wherein the borohydride ligand is facially coordinated to the iron center in each complex. Density functional methods have been employed to explain the bonding in these unusual iron(II) centers. Despite the differences in spin states, short Fe–B distances are observed in both complexes and there is significant theoretical evidence to support a substantial bonding interaction between the iron and boron nuclei. In light of this interaction, we suggest that these complexes can be described as (L_3)Fe(η^4-H_3BH) complexes

Vibrational Spectroscopy and Analysis of Pseudo-tetrahedral Complexes with Metal Imido Bonds

A number of assignments have been previously posited for the metal−nitrogen stretch (ν(M-NR)), the N−R stretch (ν(MN−R)), and possible ligand deformation modes associated with terminally bound imides. Here we examine mononuclear iron(III) and cobalt(III) imido complexes of the monoanionic tridentate ligand [PhBP_(3)] ([PhBP_(3)] = [PhB(CH_(2)PPh_(2))_(3)]^(-)) to clarify the vibrational features for these trivalent metal imides. We report the structures of [PhBP_(3)]Fe≡N^(t)Bu and [PhBP_(3)]Co≡N^(t)Bu. Pseudo-tetrahedral metal imides of these types exhibit short bond lengths (ca. 1.65 Å) and nearly linear angles about the M−N−C linkages, indicative of multiple bond character. Furthermore, these compounds give rise to intense, low-energy visible absorptions. Both the position and the intensity of the optical bands in the [PhBP_(3)]M≡NR complexes depend on whether the substituent is an alkyl or aryl group. Excitation into the low-energy bands of [PhBP_(3)]Fe≡N^(t)Bu gives rise to two Raman features at 1104 and 1233 cm^(-1), both of which are sensitive to ^(15)N and ^(2)H labeling. The isotope labeling suggests the 1104 cm^(-1) mode has the greatest Fe−N stretching character, while the 1233 cm^(-1) mode is affected to a lesser extent by ^(15)N substitution. The spectra of the deuterium-labeled imides further support this assertion. The data demonstrate that the observed peaks are not simple diatomic stretching modes but are extensively coupled to the vibrations of the ancillary organic group. Therefore, describing these complexes as simple diatomic or even triatomic oscillators is an oversimplification. Analogous studies of the corresponding cobalt(III) complex lead to a similar set of isotopically sensitive resonances at 1103 and 1238 cm^(-1), corroborating the assignments made in the iron imides. Very minimal changes in the vibrational frequencies are observed upon replacement of cobalt(III) for iron(III), suggesting similar force constants for the two compounds. This is consistent with the previously proposed electronic structure model in which the added electron resides in a relatively nonbonding orbital. Replacement of the tBu group with a phenyl ring leads to a significantly more complicated resonance Raman spectrum, presumably due to coupling with the vibrations of the phenyl ring. Polarization studies demonstrate that the observed modes have A1 symmetry. In this case, a clearer resonance enhancement of the signals is observed, supporting a charge transfer designation for the electronic transitions. A series of isotope-labeling experiments has been carried out, and the modes with the greatest metal−nitrogen stretching character have been assigned to peaks at 960 and 1300 cm^(-1) in both the iron and cobalt [PhBP_(3)]M≡NPh complexes. These results are consistent with a multiple M−N bond for these metal imides

Port-access coronary artery bypass grafting: A proposed surgical method

AbstractMinimally invasive surgical methods have been developed to provide patients the benefits of open operations with decreased pain and suffering. We have developed a system that allows the performance of cardiopulmonary bypass and myocardial protection with cardioplegic arrest without sternotomy or thoracotomy. In a canine model, we successfully used this system to anastomose the internal thoracic artery to the left anterior descending coronary artery in nine of 10 animals. The left internal thoracic artery was dissected from the chest wall, and the pericardium was opened with the use of thoracoscopic techniques and single lung ventilation. The heart was arrested with a cold blood cardioplegic solution delivered through the central lumen of a balloon occlusion catheter (Endoaortic Clamp; Heartport, Inc., Redwood City, Calif.) in the ascending aorta, and cardiopulmonary bypass was maintained with femorofemoral bypass. An operating microscope modified to allow introduction of the 3.5× magnification objective into the chest was positioned through a 10 mm port over the site of the anastomosis. The anastomosis was performed with modified surgical instruments introduced through additional 5 mm ports. In the cadaver model (n = 7) the internal thoracic artery was harvested and the pericardium opened by means of similar techniques. A precise arteriotomy was made with microvascular thoracoscopic instruments under the modified microscope on four cadavers. In three other cadavers we assessed the exposure provided by a small anterior incision (4 to 6 cm) over the fourth intercostal space. This anterior port can assist in dissection of the distal internal thoracic artery and provides direct access to the left anterior descending, circumflex, and posterior descending arteries. We have demonstrated the potential feasibility of grafting the internal thoracic artery to coronary arteries with the heart arrested and protected, without a major thoracotomy or sternotomy. (J THORAC CARDIOVASC SURG 1996;111:567-73

Bis(α-diimine)iron Complexes: Electronic Structure Determination by Spectroscopy and Broken Symmetry Density Functional Theoretical Calculations

The electronic structure of a family comprising tetrahedral (α-diimine)iron dichloride, and tetrahedral bis(α-diimine)iron compounds has been investigated by Mössbauer spectroscopy, magnetic susceptibility measurements, and X-ray crystallography. In addition, broken-symmetry density functional theoretical (B3LYP) calculations have been performed. A detailed understanding of the electronic structure of these complexes has been obtained. A paramagnetic (S_t = 2), tetrahedral complex [Fe^(II)(^4L)_2], where (^4L)^(1−) represents the diamagnetic monoanion N-tert-butylquinolinylamide, has been synthesized and characterized to serve as a benchmark for a Werner-type complex containing a tetrahedral Fe^(II)N_4 geometry and a single high-spin ferrous ion. In contrast to the most commonly used description of the electronic structure of bis(α-diimine)iron(0) complexes as low-valent iron(0) species with two neutral α-diimine ligands, it is established here that they are, in fact, complexes containing two (α-diiminato)^(1−•) π radical monoanions and a high-spin ferrous ion (in tetrahedral N_4 geometry) (S_(Fe) = 2). Intramolecular antiferromagnetic coupling between the π radical ligands (S_(rad) = 1/2) and the ferrous ion (S_(Fe) = 2) yields the observed S_t = 1 ground state. The study confirms that α-diimines are redox noninnocent ligands with an energetically low-lying antibonding π^* lowest unoccupied molecular orbital which can accept one or two electrons from a transition metal ion. The (α-diimine)FeCl_2 complexes (St = 2) are shown to contain a neutral α-diimine ligand, a high spin ferrous ion, and two chloride ligands

XAS Characterization of a Nitridoiron(IV) Complex with a Very Short Fe-N Bond

X-ray absorption spectroscopy has been used to characterize the novel nitridoiron(IV) units in two [PhBP^R_3]Fe(N) complexes (R = iPr and CyCH_2) and obtain direct spectroscopic evidence for a very short Fe−N distance. The distance of 1.51−1.55 Å reflects the presence of an FeN triple bond in accord with the observed Fe_≡N vibration observed for one of these species (ν_(FeN) = 1034 cm^(-1)). This highly covalent bonding interaction results in the appearance of an unusually intense pre-edge peak, whose estimated area of 100(20) units is much larger than those of the related tetrahedral complexes with Fe^I−N_2−Fe^I, Fe^(II)−NPh_2, and Fe^(III)_≡NAd motifs, and those of recently described six-coordinate Fe^V≡N and Fe^V≡IN complexes. The observation that the Fe^(IV)−N distances of two [PhBPR_3]Fe(N) complexes are shorter than the Fe^(IV)−O bond lengths of oxoiron(IV) complexes may be rationalized on the basis of the greater π basicity of the nitrido ligand than the oxo ligand and a lower metal coordination number for the Fe(N) complex

High-resolution VLA low radio frequency observations of the Perseus cluster: radio lobes, mini-halo and bent-jet radio galaxies

We present the first high-resolution 230-470 MHz map of the Perseus cluster obtained with the Karl G. Jansky Very Large Array. The high dynamic range and resolution achieved has allowed the identification of previously-unknown structures in this nearby galaxy cluster. New hints of sub-structures appear in the inner radio lobes of the brightest cluster galaxy NGC 1275. The spurs of radio emission extending into the outer X-ray cavities, inflated by past nuclear outbursts, are seen for the first time at these frequencies, consistent with spectral aging. Beyond NGC 1275, we also analyze complex radio sources harbored in the cluster. Two new distinct, narrowly-collimated jets are visible in IC 310, consistent with a highly-projected narrow-angle tail radio galaxy infalling into the cluster. We show how this is in agreement with its blazar-like behavior, implying that blazars and bent-jet radio galaxies are not mutually exclusive. We report the presence of filamentary structures across the entire tail of NGC 1265, including two new pairs of long filaments in the faintest bent extension of the tail. Such filaments have been seen in other cluster radio sources such as relics and radio lobes, indicating that there may be a fundamental connection between all these radio structures. We resolve the very narrow and straight tail of CR 15 without indication of double jets, so that the interpretation of such head-tail sources is yet unclear. Finally, we note that only the brightest western parts of the mini-halo remain, near NGC 1272 and its bent double jets.Comment: 17 pages, 12 figures, Accepted for publication in MNRA