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1. The anions CH(3)O-(-)CO and CH(3)OCO-(-)CO are both methoxide anion donors. The processes CH(3)O-(-)CO --> CH(3)O(-) + CO and CH(3)OCO-CO --> CH(3)O(-) + 2CO have DeltaG values of +8 and -68 kJ mol(-1), respectively, at the CCSD(T)/6-311++G(2d, 2p)//B3LYP/6-311++G(2d,2p) level of theory. 2. The reactions CH(3)OCOCO(2) (-) --> CH(3)OCO(2) (-) + CO (DeltaG = -22 kJ mol(-1)) and CH(3)COCH(O(-))CO(2)CH(3) --> CH(3)COCH(O(-))OCH(3) + CO (DeltaG = +19 kJ mol(-1)) proceed directly from the precursor anions via the transition states (CH(3)OCO...CO(2))(-) and (CH(3)COCHO...CH(3)OCO)(-), respectively. 3. Anion CH(3)COCH(O(-))CO(2)CH(3) undergoes methoxide anion transfer and loss of two molecules of CO in the reaction sequence CH(3)COCH(O(-))CO(2)CH(3) --> CH(3)CH(O(-))COCO(2)CH(3) --> [CH(3)CHO (CH(3)OCO-(-)CO)] --> CH(3)CH(O(-))OCH(3) + 2CO (DeltaG = +9 kJ mol(-1)). The hydride ion transfer in the first step is a key feature of the reaction sequence.

Electronic supplementary information (ESI) available: Tables S1 and S1(a): Anion geometries and energies of reaction pathway for the CS2 addition to the singlet phenyl anion.Tables S2 and S2(a):Anion geometries and energies of reaction pathway for the collision induced dissociation of the singlet PhCOS- anion. Tables S3 and S3(a): Anion geometries and energies for the possible reaction pathway for the CS2 addition to the singletBenzyl anion.Tables S4 and S4(a):Anion geometries and energies of reaction pathway for the interconversion of the singlet anion o-CH3(C6H4)- to singlet PhCH2 -. Tables S5 and S5(a): Anion geometries and energies of reaction pathway for the interconversion of the singlet PhCH2CH2 -. Tables S6 and S6(a): Potential energy surface for the dissociation of the singlet PhCH2CH2CS2 - anion. Tables S7 and S7(a): Potential energy surface of dissociation of the singlet PhCH2CH2CO2 - anion. See DOI: 10.1039/b916477d Selected carbanions react with carbon disulfide in a modified LCQ ion trap mass spectrometer to form adducts, which when collisionally activated, decompose by processes which in some cases identify the structures of the original carbanions. For example (i) C6H5 - + CS2 →C6H5CS2 - →C6H5S- + CS, occurs through a 3-membered ring ipso transition state, and (ii) the reaction between C6H5CH2 - and CS2 gives an adduct which loses H2S, whereas the adduct(s) formed between o-CH3C6H5 - and CS2 loses H2S and CS. Finally, it is shown that decarboxylation of C6H5CH2CH2CO2 - produces the b-phenylethyl anion (PhCH2CH2 -), and that this thermalized anion reacts with CS2 to form C6H5CH2CH2CS2 - which when energized fragments specifically by the process C6H5CH2CH2CS2 - →C6H5CH2 -CHC(S)SH→ [(C6H5CH2CH=C=S) -SH]→C6H5CH2CCS- + H2S. Experimental findings of processes (ii) and (iii) were aided by deuterium labelling studies, and all reaction profiles were studied by theoretical calculations at the UCCSD(T)/6-31+G(d,p)//B3LYP/6-31+G(d,p) level of theory unless indicated to the contrary.

Collision-induced activation of deprotonated trimethylamine N-oxide yields the two anions [N(CH2)3]– and [ON(CH2)2]– following losses of H2O and CH4, respectively. These two anions decompose by minor losses of H• and H2 when collisionally activated: no other fragmentations are noted. Calculations at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31+G(d) level of theory indicate that these trigonal anions are stable, and should not rearrange following collisional activation. Collisional-induced charge stripping of the anions [N(CH2)3]– and [ON(CH2)2]–, respectively, form N(CH2)3 and ON(CH2)2. Some of these neutrals are energised and undergo rearrangement and dissociation. From a consideration of experiment and theory, it is proposed (i) that energised N(CH2)3 may cyclise to form the 1-aziridinylcarbinyl radical. This species may ring open to CH2=NCH2CH2 which then decomposes to CH2N and C2H4 and (ii) energised ON(CH2)2 may undergo OC cyclisation followed by ring opening to energised CH2=NCH2O which may fragment to yield CH2N and CH2O.

Peptides and proteins may contain post-translationally modified phosphorylated amino acid residues, in particular phosphorylated serine (pSer), threonine (pThr) and tyrosine (pTyr). Following earlier work by Lehmann et al., the [M-H] - anions of peptides containing pSer and pThr functionality show loss of the elements of H 3 P0 4 . This process, illustrated for Ser (and using a model system), is CH 3 CONH - C(CH 2 ΟPΟ 3 H 2 )CONHCH 3 → [CH3CONHC(=CH2)CONHCH3 (-OPO3H2)] (a) → [CH3CONHC(=CH 2 )CONHCH3-H]- + H 3 P0 4 , a process endothermic by 83 kj mol -1 at the MP2/ 6-31++G(d,p)//HF/6-31++G(d,p) level of theory. In addition, intermediate (a) may decompose to yield CH 3 CONHC(=CH 2 )CONHCH 3 + H 2 PO[ in a process exothermic by 3 kJ mol- 1 . The barrier to the transition state for these two processes is 49 kJ mol- 1 . Characteristic cleavages of pSer and pThr are more energetically favourable than the negative ion backbone cleavages of peptides described previously. In contrast, loss of HPO 3 from [M-H] - is characteristic of pTyr. The cleavage INH 2 CH(CH 2 -C 6 H 4 -OP0 3 H-)C0 2 H] → [NH 2 C(CH 2 -C 6 H 4 -O-)C0 2 H (HPO3)] (b)→ NH 2 CH(CH 2 -c 6 H 4 -O-)c0 2 H + HPO 3 is endothermic by 318 kJ mol- 1 at the HF/6-31+G(d)//AM1 level of theory. In addition, intermediate (b) also yields NH 2 CH(CH 2 -C 6 H4-OH)C0 2 H + PO - 3 (reaction endothermic by i37kJmol- 1 ). The two negative ion cleavages of pTyr have a barrier to the transition state of 198 kJ mol- 1 (at the HF/6-31+G(d)//AM1 level of theory) comparable with those already reported for negative ion backbone cleavages.

The glandular skin secretion of the Eastern Dwarf Tree Frog Litoria fallax contains nine peptides named fallaxidins. The sequences of these peptides were elucidated using a combination of positive and negative electrospray mass spectrometry together with Edman sequencing. Among these peptides are: (i) fallaxidins 1.1 and 2.1 which have the sequences YFPIPI-NH 2 and FWPFM-NH 2 . The activities of these peptides are unknown, but it has been shown that they are not smooth muscle active, opioids or antimicrobially active, nor do they effect proliferation of lymphocytes; (ii) two weakly active antibiotics, fallaxidins 3.1 and 3.2 (e.g. fallaxidin 3.1, GLLDLAKHVIGIASKL-NH2), and a moderately active antibiotic fallaxidin 4.1 (GLLSFLPKVIGVIGHLIHPPS-OH). Fallaxidin 4.1 has an unusual sequence for an antibiotic, containing three Pro residues together with a C-terminal CO 2 H group. cDNA cloning has confirmed the identity of the nine isolated peptides from L. fallax, together with five additional peptides not detected in the peptide profile. The pre-regions of the nine preprofallaxidins are conserved and similar to those of the caerin peptides from L. caerulea and L. splendida, suggesting that the fallaxidin and caerin peptides, although significantly different in sequence, originated from a common ancestor gene.

Chronic kidney disease (CKD) affects 8 to 16% people worldwide, with an increasing incidence and prevalence of end-stage kidney disease (ESKD). The effective management of CKD is confounded by the inability to identify patients at high risk of progression while in early stages of CKD. To address this challenge, a renal biopsy transcriptome-driven approach was applied to develop noninvasive prognostic biomarkers for CKD progression. Expression of intrarenal transcripts was correlated with the baseline estimated glomerular filtration rate (eGFR) in 261 patients. Proteins encoded by eGFR-associated transcripts were tested in urine for association with renal tissue injury and baseline eGFR. The ability to predict CKD progression, defined as the composite of ESKD or 40% reduction of baseline eGFR, was then determined in three independent CKD cohorts. A panel of intrarenal transcripts, including epidermal growth factor (EGF), a tubule-specific protein critical for cell differentiation and regeneration, predicted eGFR. The amount of EGF protein in urine (uEGF) showed significant correlation (P0.001) with intrarenal EGF mRNA, interstitial fibrosis/tubular atrophy, eGFR, and rate of eGFR loss. Prediction of the composite renal end point by age, gender, eGFR, and albuminuria was significantly (P0.001) improved by addition of uEGF, with an increase of the C-statistic from 0.75 to 0.87. Outcome predictions were replicated in two independent CKD cohorts. Our approach identified uEGF as an independent risk predictor of CKD progression. Addition of uEGF to standard clinical parameters improved the prediction of disease events in diverse CKD populations with a wide spectrum of causes and stages.

The migratory aptitudes of alkyl groups in the gas phase 1,2-Wittig rearrangement have been determined experimentally as follows. An anion Ph––C(OR1)(OR2), on collisional activation, competitively rearranges to the two 1,2-Wittig ions PhC(R1)(OR2)(O–) and PhC(R2)(OR1)(O–) [R1 and R2 = alkyl and R1 iso-Pr > Et > Me): a trend generally taken to indicate a radical reaction. However, a Hammett investigation of the relative losses of MeOH from R–C6H4––C(OMe)2 shows this loss decreases markedly as R becomes more electron withdrawing, an observation not consistent with a radical reaction. Ab initio calculations [at the CISD/6-311++G**//RHF (and UHF)/6-311++G** levels of theory] have been used to construct potential surface maps for the model 1,2-Wittig systems –CH2OMe→ EtO–, and –CH2OEt→PrO–. Each of these exothermic reactions involves migration of an alkyl anion. There are no discrete intermediates in the reaction pathways. There is no indication of a radical pathway for either rearrangement. It is proposed that the gas phase 1,2-Wittig rearrangement involves an anionic migration, and that it is not the barrier to the early saddle point but the Arrhenius A factor (or the frequency factor of the QET), which controls the rate of the rearrangement. Weak H-bonding between the alkyl anion and the oxygen of the neutral carbonyl species acts as a pivot in holding the molecular complex together during the migration process. This electrostatic interaction increases with an increase in the number of hydrogens able to H-bond to oxygen and with the number of equivalent ways this H-bonding can occur. The relative migratory aptitude of alkyl anions bound within these molecular complexes is tert-Bu– > iso-Pr– > Et– Me–, an order quite different from the migratory aptitudes of anions expected from thermodynamic considerations. This conclusion indicates that great care must be exercised in utilising thermodynamically derived migratory aptitudes to explain the course of a kinetically controlled reaction in the gas phase.

Summary Fatty acid (FA) composition was analysed in unincubated eggs of 200 hens. The birds were either from lines (RIR, line 33, SS, line 44) and crosses where feed efficiency of egg-mass production had been improved over eight to nine generations of reciprocal recurrent selection, or from a control population. The somewhat more efficient line 33 had less saturated FA (SAT FA), but a higher ratio for PUFA (polyunsaturated FA)/SAT. Selection decreased SAT FA but increased PUPA/SAT, and heterosis acted in the same direction. Thus it appears that modern poultry breeding affects egg composition in a dietary desirable direction. Zusammenfassung Genetische Wirkungen auf Fettsaurezusammensetzung in Eidotter Fettsaurezusammensetzung (FA) wurde analysiert von nicht inkubierten Eiern von 200 Hennen. Diese waren von Reinzucht- und Kreuzungsherkunften, die uber 8–9 Generationen auf Eimassefutterverwertung durch RRS bearbeitet worden waren, sowie von deren Kontrollgruppen. Die etwas effizienteren Rhode Island Red (Linie 33) hatten etwas geringeren Gehalt an gesattigten FA (SA) und ein hoheres Verhaltnis PUFA (mehrfach ungesattigte FA)/SAT. Selektion verringerte SAT und steigerte PUFA/SAT, heterosis wirkte in dieselbe Richtung. Es scheint daher, das die moderene Legehennenzuchtung die Eierzusammensetzung in dietatisch gunstiger Richtung verandert.

Polymerase chain reaction (PCR)-based genital human papillomavirus (HPV) detection methods that use consensus primers have enabled the broad-spectrum detection of most characterized HPV types. In addition, these techniques have allowed the identification of potentially novel viral sequences in clinical specimens. These methods were used to determine the partial L1 nucleotide sequence (the region generated by L1 consensus primers MY09 and MY11) of four novel viruses. The prevalence of these viruses in cytologically normal and dysplastic cervical specimens and in invasive cervical cancer was also determined. The partial DNA sequences of W13B (MM4), PAP291 (MM7), PAP155 (MM8), and PAP238a (MM9) are most similar to HPV-51, -61, -61, and -34, respectively. Prevalence studies suggest that W13B and PAP238a are cancer-associated, while PAP155 and PAP291 appear to be lower-risk viruses.

There is significant correspondence between certain skeletal rearrangement processes of close-shell organic anions in the condensed and gas phases. Examples of such correspondence include the acyloin, acyl oxyacetate, anionic oxy Cope, anionic Wolff, benzilic acid, Dieckmann, Lossen, Smiles and Wittig rearrangements. In contrast, there are some rearrangements observed in the condensed phase, which are either minor or do not occur at all in the gas phase. The Favorskii, Tiemann and Carroll rearrangements fall into this category. Finally, there are some gas phase rearrangements which have no condensed phase analogy: for example the negative ion pinacol/pinacolone and Beckmann rearrangements. These, and related processes are discussed in this Review.

Deprotonated 1,2-diols and β-methoxyhydrins often eliminate ROH (R=H, Me) on collisional activation in the gas phase. These losses do not involve a negative ion pinacol rearrangement in acyclic systems in which there are no conformational restraints on the relative positions of the reacting groups. In the case of β-methoxyhydrins, labeling studies show that the product ion is formed by the losses of a methoxide ion and a proton from adjacent positions. The absence of a deuterium isotope effect for this process precludes the operation of an elimination process: we propose that the loss of methanol proceeds via an epoxide cyclization viz. Me 2 C(OMe)C(O - )(Me) 2 →(MeO - )-CH 3 (Me)C-C(Me) 2 →CH 2 =C(Me)C(O - )(Me) 2 +MeOH

Deprotonated pyruvates and hydroxyacetates, upon collisional activation, undergo loss of CO by anionic rearrangement through alkoxycarbonyl ion complexes, e.g. [graphic omitted] and [graphic omitted] Such processes have been substantiated by labelling (2H, 13C), and production studies.

The collisional activation mass spectra of deprotonated (acyloxy)acetates [R 1 CO 2 C − (R 2 )CO 2 R 3 ] show a number of decompositions (e.g., losses of CO, C 2 O 2 , R 3 OH, and HCO 2 R 3 ) that occur following the 1,2 anionic rearrangment R 1 CO 2 C − (R 2 )CO 2 R 3 →R 1 COC(R 2 )(O − )CO 2 R 3 . A similar gas-phase rearrangement is proposed for deprotonated α-acyloxyacetonitriles, i.e., RCO 2 C − (H)CN→RCOCH(O − )CN

Both radicals and (even-electron) neutrals are lost when even-electron organic negative ions are subjected ot collisional activation in the gas phase. Generally, radical loss is less pronounced and less diagnostic (of some structural feature) than the ubiquitous (even-electron) neutral loss. There are exceptions to this generalisation: these often fall into one of the following classifications, i.e. There is a further type of “radical” loss, which is a stepwise process involving loss of H and (R − H). This occurs in particular cases and only when R is alkyl(⩾Et). The reactions are diverse but they may all be rationalized as proceeding through five-membered ring intermediates. The loss of “C 2 H 5 ” from an alkylcarboxylate anion is a suitable example

Deprotonated 1,2-diols and β-methoxyhydrins often eliminate ROH (R=H, Me) on collisional activation in the gas phase. These losses do not involve a negative ion pinacol rearrangement in acyclic systems in which there are no conformational restraints on the relative positions of the reacting groups. In the case of β-methoxyhydrins, labeling studies show that the product ion is formed by the losses of a methoxide ion and a proton from adjacent positions. The absence of a deuterium isotope effect for this process precludes the operation of an elimination process: we propose that the loss of methanol proceeds via an epoxide cyclization viz. Me 2 C(OMe)C(O - )(Me) 2 →(MeO - )-CH 3 (Me)C-C(Me) 2 →CH 2 =C(Me)C(O - )(Me) 2 +MeOH

There is significant correspondence between certain skeletal rearrangement processes of close-shell organic anions in the condensed and gas phases. Examples of such correspondence include the acyloin, acyl oxyacetate, anionic oxy Cope, anionic Wolff, benzilic acid, Dieckmann, Lossen, Smiles and Wittig rearrangements. In contrast, there are some rearrangements observed in the condensed phase, which are either minor or do not occur at all in the gas phase. The Favorskii, Tiemann and Carroll rearrangements fall into this category. Finally, there are some gas phase rearrangements which have no condensed phase analogy: for example the negative ion pinacol/pinacolone and Beckmann rearrangements. These, and related processes are discussed in this Review.

1. The anions CH(3)O-(-)CO and CH(3)OCO-(-)CO are both methoxide anion donors. The processes CH(3)O-(-)CO --CH(3)O(-) + CO and CH(3)OCO-CO --CH(3)O(-) + 2CO have DeltaG values of +8 and -68 kJ mol(-1), respectively, at the CCSD(T)/6-311++G(2d, 2p)//B3LYP/6-311++G(2d,2p) level of theory. 2. The reactions CH(3)OCOCO(2) (-) --CH(3)OCO(2) (-) + CO (DeltaG = -22 kJ mol(-1)) and CH(3)COCH(O(-))CO(2)CH(3) --CH(3)COCH(O(-))OCH(3) + CO (DeltaG = +19 kJ mol(-1)) proceed directly from the precursor anions via the transition states (CH(3)OCO...CO(2))(-) and (CH(3)COCHO...CH(3)OCO)(-), respectively. 3. Anion CH(3)COCH(O(-))CO(2)CH(3) undergoes methoxide anion transfer and loss of two molecules of CO in the reaction sequence CH(3)COCH(O(-))CO(2)CH(3) --CH(3)CH(O(-))COCO(2)CH(3) --[CH(3)CHO (CH(3)OCO-(-)CO)] --CH(3)CH(O(-))OCH(3) + 2CO (DeltaG = +9 kJ mol(-1)). The hydride ion transfer in the first step is a key feature of the reaction sequence.

The gas-phase Smiles reaction of RC 6 H 6 O(CH 2 ) n O − (n = 2 or 3) is an ipso rearrangement which is strongly influenced by the nature of the substituent R. Electron-withdrawing groups enhance the rearrangement. When the substituent R is halogen or MeO, and occupies the ortho position, ortho cyclization competes with the Smiles rearrangement

[1,3] Sigmatropic rearrangements, e.g. R 1 R 2 C(O − )CHCH 2 → R 1 C(O − )CHCH 2 R 2 and/or R 2 C(O − )CHCH 2 R 1 , only occur under special circumstances in the gas phase. No rearrangements occurs when R 1 and R 2 are alkyl or phenyl; when either R group benzyl, minor rearrangement is observed. When the R groups comprise a cycloalkyl ring, [1,3] rearrangement occurs readily for small strained rings (e.g. cycloropyl and cyclobutyl) but not at all for cyclopentyl and cyclohexyl systems.

Both radicals and (even-electron) neutrals are lost when even-electron organic negative ions are subjected ot collisional activation in the gas phase. Generally, radical loss is less pronounced and less diagnostic (of some structural feature) than the ubiquitous (even-electron) neutral loss. There are exceptions to this generalisation: these often fall into one of the following classifications, i.e. There is a further type of “radical” loss, which is a stepwise process involving loss of H and (R − H). This occurs in particular cases and only when R is alkyl(⩾Et). The reactions are diverse but they may all be rationalized as proceeding through five-membered ring intermediates. The loss of “C 2 H 5 ” from an alkylcarboxylate anion is a suitable example

The collisional activation mass spectra of deprotonated (acyloxy)acetates [R 1 CO 2 C − (R 2 )CO 2 R 3 ] show a number of decompositions (e.g., losses of CO, C 2 O 2 , R 3 OH, and HCO 2 R 3 ) that occur following the 1,2 anionic rearrangment R 1 CO 2 C − (R 2 )CO 2 R 3 →R 1 COC(R 2 )(O − )CO 2 R 3 . A similar gas-phase rearrangement is proposed for deprotonated α-acyloxyacetonitriles, i.e., RCO 2 C − (H)CN→RCOCH(O − )CN

Peptides and proteins may contain post-translationally modified phosphorylated amino acid residues, in particular phosphorylated serine (pSer), threonine (pThr) and tyrosine (pTyr). Following earlier work by Lehmann et al., the [M-H]- anions of peptides containing pSer and pThr functionality show loss of the elements of H3PO4. This process, illustrated for Ser (and using a model system), is CH3CONH-C(CH2OPO3H2)CONHCH(3) --[CH3CONHC(==CH2)CONHCH3 (-OPO3H2)] (a) --[CH3CONHC(==CH2)CONHCH3-H]- + H3PO4, a process endothermic by 83 kJ mol(-1) at the MP2/6-31++G(d,p)//HF/6-31++G(d,p) level of theory. In addition, intermediate (a) may decompose to yield CH3CONHC(==CH2)CONHCH3 + H2PO4 - in a process exothermic by 3 kJ mol(-1). The barrier to the transition state for these two processes is 49 kJ mol(-1). Characteristic cleavages of pSer and pThr are more energetically favourable than the negative ion backbone cleavages of peptides described previously. In contrast, loss of HPO3 from [M-H]- is characteristic of pTyr. The cleavage [NH2CH(CH2-C6H4-OPO3H-)CO2H] --[NH2C(CH2-C6H4-O-)CO2H (HPO3)] (b) --NH2CH(CH2-C6H4-O-)CO2H + HPO3 is endothermic by 318 kJ mol(-1) at the HF/6-31+G(d)//AM1 level of theory. In addition, intermediate (b) also yields NH2CH(CH2-C6H4-OH)CO2H + PO3 - (reaction endothermic by 137 kJ mol(-1)). The two negative ion cleavages of pTyr have a barrier to the transition state of 198 kJ mol(-1) (at the HF/6-31+G(d)//AM1 level of theory) comparable with those already reported for negative ion backbone cleavages.

Calculations at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31+G(d) level of theory have shown that cyclization of both the ground state triplet and the corresponding singlet state of CCCSi may rearrange to give cyclic isomers which upon ring opening may reform linear C(3)Si isomers in which the carbon atoms are scrambled. The cyclization processes are energetically favorable with barriers to the transition states from 13 to 16 kcal mol(-1). This should be contrasted with the analogous process of triplet CCCC to triplet rhombic C(4), which requires an excess energy of 25.8 kcal mol(-1). A similar cyclization of doublet CCCP requires 50.4 kcal mol(-1) of excess energy; this should be contrasted with the same process for CCCN, which requires 54.7 kcal mol(-1) to effect cyclization.

The negative ion spectrum of MeOCO N OCH2CHCH2 shows a major peak corresponding to the methylcarbonate anion MeOCO−2. Evidence is presented which suggests that this is formed by the successive rearrangement pathway The first step could involve either a 1,2 or 1,4 anionic rearrangement; the second step is a 1,2 anionic rearrangement.

Deprotonated isocamphanones rearrange to deprotonated camphor in the gas phase, presumably via the intermediacy of a homoenolate anion.

A key requirement for agricultural research is access to rapid, accurate and inexpensive analyses. This is particularly the case, once desirable crop traits are identified and plant breeders attempt to translate these results into high yielding crops having favourable characteristics. The utility of capillary electrophoresis and diffuse reflectance mid-infrared spectroscopy as tools for rapid analyses of value to plant breeding projects will be described.

α-Alkoxyvinyltrimethylsilanes deprotonate to form two species −CHC(SiMe3)OR and CH2C(Si(Me)2CH2−)OR. The silylcarbanion undergoes the unusual rearrangement reaction CH2C(Si(Me3)2CH2−)OR → ((CH2CO)Me2RSiCH2−) Me2RSiCH2− + CH2CO. Loss of (R-H) occurs when R ≥ Et; it is suggested that this is a reaction of the vinvl anion system.

An electron monochromator mass spectrometer was used to study the resonant electron energies versus negative ion masses of the organophosphate insecticides dicapthion, EPN, ethion, fenitrothion, leptophos, leptophosoxon, paraoxon, and parathion. Each compound yielded a unique two-dimensional electron energy/mass spectrum. The most abundant ions are produced with electrons of energies between 0.03 and 1 eV, but ions result also from capture of electrons with energies ranging to 8.5 eV. Both resonance electron capture ions and dissociative electron capture ions are produced with electrons of energies ranging from 0.03 to 8.5 eV, and ions may have as many as three observable resonance states from which they are formed. Substituted thiophenoxide ions are postulated to arise by rearrangement of the parent thiophosphate ions through a spiro intermediate. Most fragment ions can be rationalized as arising through simple homolytic cleavage of the parent radical anions.

Introduction of anaesthesia with CO2/O2 (60% to 40%) is possible within 90 and 120 seconds. There are moderate to excessive excitations occurring as part of state II of anaesthesia. Anaesthesia (during castration) in CO2/O2-atmosphere produces excellent analgesia and relaxation. The duration of castration surgery is much shorter under CO2-anaesthesia than without anaesthesia. Blood cortisol levels are significantly higher after castration without CO2-anaesthesia. About 5 minutes after CO2/O2-anaesthesia and castration surgery, piglets are already awake and standing.

Urinary pteridine patterns and creatinine concentrations were determined in pigs of the breeds Piétrain, Deutsche Landrasse and their crossbreds. Also the influence of the halothane genotypes, of different feeding and of treadmill exercise was examined. We conclude that creatinine concentration in pig urine is not a reliable reference parameter for the pteridine excretion. Creatinine values were significantly influenced by breed and feeding. The pteridine pattern of pigs' urine depends on the breed and correlates with other metabolic parameters. Stress is reflected by altered pteridine concentrations.

Allyl vinyl ether is reported to undergo a facile Wittig rearrangement to yield penta-1,4-dien-3-ol under base- catalysed conditions in the condensed phase. In marked contrast, the Wittig rearrangement is not a major reaction in the gas phase. Instead, initial rearrangement occurs by a Claisen process and subsequent fragmentations involve some of the most complex interconversions yet proposed for negative ions.

An operon encoding four proteins required for bacterial cellulose biosynthesis (bcs) in Acetobacter xylinum was isolated via genetic complementation with strains lacking cellulose synthase activity. Nucleotide sequence analysis indicated that the cellulose synthase operon is 9217 base pairs long and consists of four genes. The four genes--bcsA, bcsB, bcsC, and bcsD--appear to be translationally coupled and transcribed as a polycistronic mRNA with an initiation site 97 bases upstream of the coding region of the first gene (bcsA) in the operon. Results from genetic complementation tests and gene disruption analyses demonstrate that all four genes in the operon are required for maximal bacterial cellulose synthesis in A. xylinum. The calculated molecular masses of the proteins encoded by bcsA, bcsB, bcsC, and bcsD are 84.4, 85.3, 141.0, and 17.3 kDa, respectively. The second gene in the operon (bcsB) encodes the catalytic subunit of cellulose synthase. The functions of the bcsA, bcsC, and bcsD gene products are unknown. Bacterial strains mutated in the bcsA locus were found to be deficient in cellulose synthesis due to the lack of cellulose synthase and diguanylate cyclase activities. Mutants in the bcsC and bcsD genes were impaired in cellulose production in vivo, even though they had the capacity to make all the necessary metabolic precursors and cyclic diguanylic acid, the activator of cellulose synthase, and exhibit cellulose synthase activity in vitro. When the entire operon was present on a multicopy plasmid in the bacterial cell, both cellulose synthase activity and cellulose biosynthesis increased. When the promoter of the cellulose synthase operon was replaced on the chromosome by E. coli tac or lac promoters, cellulose production was reduced in parallel with decreased cellulose synthase activity. These observations suggest that the expression of the bcs operon is rate-limiting for cellulose synthesis in A. xylinum.

We developed a polymerase chain reaction DNA amplification system using two distinct consensus oligonucleotide primer sets for the improved detection and typing of a broad spectrum of human genital papillomavirus (HPV) sequences, including those of novel viruses. The system incorporates one primer set designed to amplify a highly conserved L1 domain and a second primer set designed to amplify a domain within the E6 gene. We used this system to analyze 48 fixed, paraffin-embedded tissue sections (41 specimens from 33 cervical carcinomas, four normal cervical tissues, and several control tissues) for the presence of HPV DNA. HPV sequences were detected in all carcinoma samples and none of the control samples. Hybridization analyses showed that the results obtained with the two amplification schemes concurred completely. This approach allowed rapid confirmation of typing results and may improve the likelihood of detecting a wide variety of HPV sequences, including those of novel HPVs.

The collision-induced mass spectra of the o-methyl and o-ethylphenoxide anions show loss of formaldehyde and acetaldehyde, respectively. These processes are rationalized in terms of a reversible rearrangement o-RC6H4O− ⇌ [(C6H4)−OR] (R = alkyl).

Reaction of benzil with HO− in the chemical ionization source of a triple-analyser mass spectrometer forms a [benzl + HO−] ion. This ion, upon collisional activation, gives a mass spectrum identical to that obtained from deprotonated benzilic acid under the same experimental conditions.

Deprotonation of cis- and trans-4-methoxycyclohexanol by HO– in the ion source of a mass spectrometer yields the (M – H)– alkoxide ions exclusively. Both of these ions, on collisional activation, form MeO–, MeO–(H2O) and eliminate MeOH. The loss of methanol forms the base peak of the spectrum, and the structure of this daughter anion is shown to be the alkoxide ion from cyclohex-3-enol for both isomers. Evidence (based on product ion, deuterium labelling and AM1 semiempirical computational studies) indicates that the loss of methanol from the trans isomer proceeds by an internal SN2 cyclisation of O– at the four position (through a 1,4-epoxycyclohexane species) followed by 3,4 elimination. A similar sequence may occur for the cis-isomer, but in this case the process is not as energetically favourable as that for the trans isomer.

Allyl vinyl ether is reported to undergo a facile Wittig rearrangement to yield penta-1,4-dien-3-ol under base- catalysed conditions in the condensed phase. In marked contrast, the Wittig rearrangement is not a major reaction in the gas phase. Instead, initial rearrangement occurs by a Claisen process and subsequent fragmentations involve some of the most complex interconversions yet proposed for negative ions.

Deprotonated pyruvates and hydroxyacetates, upon collisional activation, undergo loss of CO by anionic rearrangement through alkoxycarbonyl ion complexes, e.g. [graphic omitted] and [graphic omitted] Such processes have been substantiated by labelling (2H, 13C), and production studies.

Deprotonation of alkyl vinyl ethers (CH2CHOR) with NH2– in the gas phase yields the two carbanions CH2OR and –CHCHOR. The former ion can be synthesized specifically using the SN2(Si) reaction CH2C(SiMe3)OR + NH2–→CH2OR + Me3SiNH2: the ion undergoes several competitive and characteristic collision-induced reactions. For example, (i) when R Et, elimination of an alkene, i.e. CH2OR→(CH2CHO)–+(R–H), and (ii) the Wittig rearrangement CH2OR [graphic omitted] CH2C(R)O–.

We report on a study of the charge-exchange reaction pp → nΔ ++ (1232) at the CERN intersecting storage rings (ISR) in the energy range √ s = 23 to 53 GeV. From our analysis of the energy dependence of the total cross-section, of the differential cross-section d σ /d t and of the decay angular distributions we find evidence that pion exchange is dominant up to √ s = 23 GeV and that ( ϱ +A 2 ) exchange dominates the reaction for √ s ⩾ 30 GeV, as described by simple Regge-pole models.

Observation of 16 μ + μ − pairs of invariant mass greater than 2.7 GeV/ c 2 in the reaction pp → μ + μ − + anything at s = 52 GeV at the CERN Intersecting Storage Rings (ISR) is reported. These events can be interpreted as originating from J(3.1) decay into μ + μ − . Their p T distribution suggests a hadronic production. The cross section for J production is given and compared to the cross section for single lepton production. We conclude that J(3.1) production cannot fully account for single lepton production.

New experimental results are presented on proton-proton elastic scattering at centre-of-mass energies square root s=23 GeV and square root s=62 GeV. The data are obtained using the Split Field Magnet detector at the CERN Intersecting Storage Rings. The absolute differential cross-sections show an energy-dependent behaviour. The position of the diffraction minimum changes from t=(-1.44+or-0.02) GeV /sup 2/ at 23 GeV to (-1.26+or-0.03) GeV/sup 2/ at 62 GeV. The cross- section at the second maximum is increasing with square root s. The connection of these observations with the hypothesis of 'geometrical scaling' is discussed. (8 refs).

Environmental factors affecting fasting metabolic rate (FMR) were quantified and a short-time recording system was developed. Discontinuous measurements of gas exchange of 1,120 medium weight brown egg layers were taken after 24 and 36 hr of starvation. Body weight (BW) and shank length (SL) were measured and feather cover and activity evaluated by scores. The FMR increased with deterioration of plumage cover. Differences between hens with complete feather cover (Score 1) and nearly naked birds (Score 4) were 8 kJ2/hr at night and 11 kJ/hr during the light phase. Fully fed hens measured during the light phase showed the same curvilinear relationship as starved birds. Only a small proportion of the heat increment generated by ingested food is used by poorly feathered hens to maintain body temperature. Gaseous exchange was affected by locomotor activity in the respiration chamber. The FMR of resting and quietly standing birds were 29.75 ± 1.00 kJ/hr and 30.55 ± 1.00 kJ/hr, respectively. During the prelaying phase, FMR showed an increment of 13 kJ/hr with a peak shortly before oviposition. The following exponential relationships between BW in kilograms, and SL in centimeters with FMR were estimated for light phase FMR = 18.52 BW .59 ± .05 kJ/hr, R2 = .11; for dark phase FMR = 15.21 BW .54 ± .04 kJ/hr, R2 = .17 and FMR = .32 SL 1.6 4 ± .10 kJ/hr, R2 = .19. In poorly feathered strains, SL was as good a predictor of body size as BW. Correcting FMR data for feather loss changed regression coefficients and allometric functions significantly: for light phase FMR = 15.47 BW .74 ± .03 kJ/hr and R2 = .15; for dark phase FMR = 13.11 BW .66 ± .03 kJ/hr and R2 = .28.

It is shown by field ionization kinetics that the ethene elimination from ionized 2-ethyl-butanoic acid is the most dominant channel at molecular ion lifetimes ⩽10 −9 s. This channel, however, becomes rapidly less important with respect to ethyl elimination at molecular ion lifetimes ⪢10 −9 s. Both eliminations occur without any detectable exchange between hydrogen or carbon atoms from different positions as shown by specific 2 H- and 13 C-labelling. The same observations are made for molecular ions decomposing in the metastable time frame of 10 −6 to 10 −5 s. On the basis of collision-induced dissociation experiments, it is demonstrated that ∼95% of the (MC 2 H 5 ) + ions have the structure of carbonyl oxygen-protonated crotonic acid which, in line with the 2 H- and 13 C-labelling, are formed by a successive, irreversible hydrogen shift from C-3 to the carbonyl oxygen and cleavage of the C-2C′-3 bond to eliminate ethyl. The remaining ∼5% of the (MC 2 H 5 ) + ions have the structure of carbonyl oxygen-protonated methacryclic acid. In line with the 2 H- and 13 C-labelling results, these ions are generated by a successive, irreversible hydrogen shift from C-3 to the carbonyl oxygen, migration of the C(OH) 2 group from C-2 to C-3, a hydrogen shift from C-3 to C-2, and eventual cleavage of the C-2C′-3 bond to eliminate ethyl. Further metastable decompositions of the (MC 2 H 5 ) + ions correspond to eliminations of molecules of water, C 2 H 2 O, and C 2 H 4 O. The water molecule contains the original hydroxylic hydrogen and one of the hydrogen atoms of C-3. The eliminated C 2 H 2 O molecule contains the C-1 and C-2 atoms, while the eliminated C 2 H 4 O molecule contains the C-3 and C-4 atoms. Combined with the obtained 2 H-labelling results, strong support, if not evidence, is provided for the intermediacy of ion/molecule complexes during the eliminations of C 2 H 2 O and C 2 H 4 O from the (MC 2 H 5 ) + ions.