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Caesarean delivery is common and can cause severe postoperative pain but injection of local anaesthetic at various sites for regional blocks or local anaesthetic infiltration may reduce this. We aimed to compare and rank these sites. We searched PubMed, Google Scholar, EMBASE and CENTRAL to June 2021 for randomised controlled trials and performed a random-effects Bayesian model network meta-analysis. The primary outcome was dose of parenteral morphine equivalents in the first 24 postoperative hours. We used surface under cumulative ranking probabilities to order techniques. We analysed 114 trials (8730 participants). The ordered mean (95% credible interval) reduction in morphine equivalents, from 34 mg with placebo, were as follows: ilio-inguinal 15 (1-32) mg; ilio-inguinal-iliohypogastric 13 (6-19) mg; transversalis fascia 11 (4-26) mg; erector spinae 11 (10-32); transverse abdominis 9 (4-13) mg; wound catheter infusion 8 (2-15) mg; quadratus lumborum 8 (1-15) mg; wound infiltration 8 (2-13) mg; and no intervention -4 (-10 to 2) mg. Ordered efficacies for injection sites were different for other relevant outcomes, including pain (to 4-6 h and to 24 h) and time to rescue analgesia: there was no single preferred route of injection. The ordered mean (95% credible interval) reduction in dynamic pain scores (0-10 scale) at 24 h compared with placebo were as follows: wound infusion 1.2 (0.2-2.1); erector spinae 1.3 (-0.5 to 3.1); quadratus lumborum 1.0 (0.1-1.8); ilio-inguinal-iliohypogastric 0.6 (-0.5 to 1.8); transverse abdominis 0.6 (-0.1 to 1.2); wound infiltration 0.5 (-0.3 to 1.3); transversalis fascia -0.8 (-3.4 to 1.9); ilio-inguinal -0.9 (-3.6 to 1.7); and no intervention -0.8 (-1.8 to 0.2). We categorised our confidence in effect sizes as low or very low.

Large-time asymptotic solutions for the reaction-diffusion front between one static reactant and one diffusing reactant are known. These states apply to single-step reactions with a mean-field reaction rate proportional to pm αn (with m, n ≥ 1), where \rho, \alpha are concentrations of the diffusing and static reactants, respectively. Such reaction kinetics commonly arise in, for example, simple corrosion models of a porous solid, subject to a diffusing reactant. Here we address a more complex two-step corrosion reaction for oxidation of uranium in a water-vapor environment. In this case, additional complexity arises through a pair of coupled reaction fronts (one with m = 2, n = 1 and the other with m = 3, n = 1). Furthermore, we allow for material expansion owing to the corrosion process and a strong dependence of diffusion coefficients on the static reactant distribution. In the large-time limit there are four main asymptotic regions, comprising two diffusion layers and two reaction fronts. Asymptotic matching of these regions allows us to construct a large-time solution that gives analytical predictions for the positions of the two propagating fronts, thickness of the diffusion layers, and concentration of diffusing species outside of the fronts. This is the first mechanistic model of uranium oxidation in water vapor and predicts a thin propagating subsurface (hydride) layer, as recently observed in atom-probe tomography experiments.

Epigenetic factors translate environmental signals into stable outcomes, but how they are influenced by regulators of plasticity remain unclear. We previously showed that androgen receptor overexpression inhibited fear memory in male mice and increased expression of the histone variant H2A.Z, a novel epigenetic regulator of memory. Here, we used conditional-inducible H2A.Z knockout mice to investigate how H2A.Z deletion influences androgenic regulation of fear memory. We showed that conditional inducible H2A.Z deletion blocked memory-enhancing effects of androgen depletion (induced by gonadectomy), and of pharmacological inhibition of the androgen receptor with flutamide. Similarly, H2A.Z deletion blocked the memory-reducing effects of DHT, and DHT treatment in cultured hippocampal neurons altered H2A.Z binding, suggesting that AR is an H2A.Z regulator in neurons. Overall, these data show that fear memory formation is regulated by interactions between sex hormones and epigenetic factors, which has implications for sex differences in fear-related disorders.

Glyphosate-resistant (GR) Palmer amaranth (Amaranthus palmeri S. Wats) is redefining row crop weed management in the southeast United States due to its widespread distribution, high competitive ability, copious seed production, and resilience against standard weed management programs. Herbicides alone are failing to provide adequate control of GR Palmer amaranth; thus, use of conventional tillage is increasing in the Southeast in order to control GR Palmer amaranth. Cultural practices consistent with maintenance of conservation tillage were evaluated to determine if they could suppress weeds in cotton (Gossypium hirsutum L.). An on-farm research and demonstration project was initiated in the fall of 2009 in Alabama, Georgia, South Carolina, and Tennessee to address well-founded concerns that conservation tillage systems were at risk because of GR Palmer amaranth. The research continued in certain states for two additional years. Cultural practices contrasted in the conservation tillage system were a no-till planted high-residue cover crop, one-time fall inversion tillage followed by the planting of a high-residue cover crop, and winter fallow only without a cover crop. Cover crop biomass yields varied from 570 to 6,790 kg ha−1 (509 to 6,063 lb ac−1) depending on location, type of cover crop, planting date, and environment. Fall inversion tillage increased cover crop biomass at all locations, likely due to preparation of a favorable seed bed for seedling establishment or alleviation of soil compaction or both. One-time fall inversion tillage reduced the number of GR Palmer amaranth escapes compared with the other treatments. Where GR Palmer amaranth densities were relatively low (approximately 1,000 plants ha−1 [405 plants ac−1] or fewer), there were few differences in the number of GR Palmer amaranth escapes among treatments. Where GR Palmer amaranth densities were relatively high (18,000 plants ha−1 [7,284 plants ac−1] or greater), winter fallow systems had higher Palmer amaranth densities escaping weed management programs compared to either cover crop system. The number of Palmer amaranth escapes declined exponentially as a function of cover crop biomass regardless of tillage. For sites with two years of data, no year by treatment interaction was detected, indicating that relative GR Palmer amaranth escape densities were sustained in each treatment for two seasons. Trends in cotton yields were the opposite of those for Palmer amaranth escapes. High-residue cover crops tended to suppress Palmer amaranth and increase cotton lint yields. However, no cultural management system consistently netted greater returns than other systems across locations and years.

D-Dimer (DD) will increase with age and recent studies have shown the upper limit of normal can be raised in those who are low risk and over 50. We studied age adjusted D-dimer (AADD) levels to assess whether pulmonary embolism (PE) could be safely excluded. This study analysed the Emergency Department (ED) Computed Tomographic Pulmonary Angiography (CTPA) requests. There were 756 requests. The parameters studied were; age, DD value, calculated AADD, CT result and Simplified Geneva Score (SGS). The primary outcome was the diagnostic performance of AADD. One hundred and eighty-five patients were included in the final cohort. Twenty-one patients had a negative DD after age adjustment. Of these one had a PE, corresponding to a failure rate of 4.76% (1 in 22). The sensitivity of AADD was 0.96 (95% CI 0.76 to 0.99) and its specificity was 0.12 (95% CI 0.08- 0.19). AADD demonstrated a reduction in false positives with one false negative, giving rise to a failure rate higher than that of other larger studies. Further study is indicated to accurately define the diagnostic characteristics for the Irish context.

A field experiment evaluated simulated salvage herbicide application injury and injury timing on cutleaf groundcherry density, biomass, seed production, and crop yield in a peanut system. Treatments included: 1) a non-treated control; 2) hand pruning; 3) diclosulam applied preemergence (PRE) alone at 27 g/ha ; 4) paraquat applied at cracking early postemergence (EPOST) at 140 g/ha followed by bentazon at 560 g/ha late postemergence (POST) alone or mixed with 5) 2,4-DB at 220 g/ha; 6) acifluorfen at 280 g/ha; 7) imazapic at 70 g/ha; or 8) chlorimuron ethyl at 9 g/ha. Hand pruning and POST herbicide treatments were performed at 1-week intervals for four weeks beginning in June of each year. Herbicide treatments do not reflect current peanut herbicide recommendations but were chosen based on likely differential cutleaf groundcherry biomass and subsequent seed production. Diclosulam applied PRE provided season-long cutleaf groundcherry control; imazapic applied POST in combination with bentazon also provided excellent control. Use of bentazon alone or mixed with chlorimuron ethyl, or hand pruning resulted in similar cutleaf groundcherry biomass and subsequent seed production compared to the non-treated control in almost all comparisons. Peanut yield reflected early-season weed interference and late season cutleaf groundcherry control. Highest yields were recorded for diclosulam PRE and POST applications containing 2,4-DB and imazapic with 6040, 5990, and 6430 kg/ha, respectively. When early-season weed control efforts fail to completely control cutleaf groundcherry, it is crucial to have effective late season herbicide options for salvage treatments in order to prevent additions to the seed bank.Nomenclature: Acifluorfen, bentazon, chlorimuron ethyl, diclosulam, imazapic, paraquat, 2,4-DB, cutleaf groundcherry, Physalis angulata (L.) PHYAN, peanut, Arachis hypogaea (L.).

We investigate methods for filtering reaction mechanisms in the angular scattering of the state-to-state reaction, H + D(2)(v(i) = 0, j(i) = 0, m(i) = 0) --> HD(v(f) = 3, j(f) = 0, m(f) = 0) + D, where v(i), j(i), and m(i) and v(f), j(f), and m(f) are initial and final vibrational, rotational, and helicity quantum numbers, respectively. The input to our filtrations is a new set of accurate quantum scattering matrix elements for total energies in the range 1.52-2.50 eV (in steps of 0.01 eV) and for total angular momentum quantum numbers in the range, 0-40, in steps of unity. We filter reaction mechanisms in both the energy domain and the time domain. The time-domain calculations employ the plane wave packet formulation of time-dependent scattering. The theoretical tools used are nearside-farside (NF) analysis of partial wave series for scattering amplitudes, together with NF local angular momentum (LAM) theory. An energy-domain LAM analysis reveals the existence of an important dynamical feature in the N scattering, a "trench" which bisects the (energy, angle) plane. We use the location of this trench to approximately filter two reaction mechanisms. Transformation to the time domain demonstrates that the two reaction mechanisms correspond to direct and delayed (by about 25 fs) scattering. Further analysis, including filtration in the time domain, shows that the pronounced LAM trench arises from the interference of the energy-domain analogues of the time-direct and time-delayed scattering. Our theory and results provide the first successful demonstration of reaction mechanism filtering carried out directly in the (energy, angle) domain. The calculations and results in this paper extend and complement earlier research reported by Monks, Connor, and Althorpe (Monks, P. D. D.; Connor, J. N. L.; Althorpe, S. C. J. Phys. Chem. A 2006, 110, 741; J. Phys. Chem. A 2007, 111, 10302).

The scattering dynamics of the state-to-state reaction H + D2 (v(i) = 0, j(i) = 0, m(i) = 0) --> HD (v(f) = 3, j(f) = 0, m(f) = 0) + D is investigated, where vi, ji, mi and vf, jf, mf are initial and final vibrational, rotational, and helicity quantum numbers, respectively. We use accurate quantum scattering matrix elements for total energies in the range 1.52-2.50 eV (calculated stepwise in 0.01 eV increments). The theoretical tools used are a nearside-farside (NF) analysis of the partial wave series (PWS) for the scattering amplitude, together with NF local angular momentum (LAM) theory. We find that the backward scattering, which is the energy-domain analog of the time-direct reaction mechanism, is N dominated, whereas the forward scattering (time-delayed analog) is a result of NF interference between the more slowly varying N and F subamplitudes. The LAM analysis reveals the existence of a "trench-ridge" structure. We also resum the PWS up to three times prior to making the NF decomposition. We show that such resummations usually provide an improved physical interpretation of the NF differential cross sections (DCSs) and NF LAMs. We analyze two resummed scattering amplitudes in more detail, where particular values of the resummation parameters give rise to unexpected unphysical behavior in the N and F DCSs over a small angular range. We analyze the cause of this unphysical behavior and describe viable workarounds to the problem. The energy-domain calculations in this paper complement the time-domain results reported earlier by Monks, P. D. D.; Connor, J. N. L.; Althorpe, S. C. J. Phys. Chem. A 2006, 110, 741.

Information is needed on the role of cover crops as a weed control alternative due to the increase in adoption of conservation-tillage in peanut production. Field experiments were conducted from autumn 1994 through autumn 1997 in Alabama to evaluate three winter cereal cover crops in a high-residue conservationtillage peanut production system. Black oat (Avena strigosa Schreb.), rye (Secale cereale L.), and wheat (Triticum aestivum L.) were evaluated for their weed-suppressive characteristics compared to a winter fallow system. Three herbicide systems were utilized: no herbicide, preemergence (PRE) herbicides followed by (fb) postemergence (POST) herbicides, and PRE fb sequential POST herbicides. The PRE fb POST herbicide input system consisted of pendimethalin at 1.12 kg ai/ha fb an additional early POST application of paraquat at 0.14 kg ai/ha plus bentazon at 0.56 kg ai/ha. The PRE fb sequential POST herbicide input system contained the aforementioned herbicides fb 2,4-DB at 0.22 kg ai/ha plus chlorimuron at 0.14 kg ai/ha applied late POST. No cover crop was effective in controlling weeds without a herbicide program. However, when black oat or rye was utilized with PRE fb POST herbicides, weed control was similar to the high input system in two out of three years. Yield increased in 14 of 27 comparisons following conservation-tilled peanut using the Brazilian cover crop management system, compared to a winter fallow system. Yields never decreased following a winter cover crop compared to winter fallow. The winter fallow, high herbicide input system yielded between 7 and 26% less peanut compared to the highest yielding system that included a winter cover crop. The Brazilian system using black oat or rye cover crop has potential to increase peanut productivity and reduce herbicide inputs for peanuts grown in the Southeast.

A three‐year field study was conducted to evaluate cotton (Gossypium hirsutum L.) response to the source and timing of nitrogen (N) on an irrigated coastal plain soil (Lucy loamy sand; Arenic Kandiudults) in south Alabama. Cotton acreage in this region has increased in the past ten years and there was a need for current data describing cotton response to N fertilization. Treatments included N sources, timing of N application (ammonium nitrate), split applications of N (ammonium nitrate and ammonium sulfate), and a no‐N check. Nitrogen sources applied preplant included: (i) ammonium nitrate (34‐0‐0); (ii) ammonium sulfate (21‐0‐0‐24.2); (iii) urea (46‐0‐0); (iv) urea–ammonium nitrate solution (UAN; 32‐0‐0); (v) UAN + ammonium thiosulfate (28‐0‐0‐5). Non‐sulfur sources were applied with and without additional sulfur (S). Times of application were preplant, first true leaf, first square, and first bloom. Two treatments received split applications of N as a 50:50 mixture of ammonium sulfate with urea...

Shredded newspaper (2.5, 7.6, 12.7, and 17.8 cm depth), chopped newspaper (2.5 and 7.6 cm), wheat straw (15.2 cm), black plastic, and plastic landscape fabric were evaluated during 1993 and 1994 in West Virginia for their effect on soil temperature, soil moisture, weed control, and yield in tomato. Shredded newspaper and wheat straw applied at 0, 2, 4, or 6 weeks after transplanting (WAT) and napropamide (2.1 kg ai/ha) plus metribuzin (0.28 kg ai/ha) applied at transplanting were evaluated during 1992 and 1993 in North Carolina for effect on weed control and tomato yield. Results from West Virginia indicated that shredded (7.6 cm) and chopped (7.6 cm) newspaper conserved moisture similar to higher application rates of the shredded material. Higher newspaper mulching rates reduced soil temperature compared to black plastic and bare ground. Chopped newspaper controlled weeds more consistently than other treatments. At least 7.6 cm of chopped newspaper mulch was required to control weeds at least 90%. Wheat straw was not as effective in controlling weeds as 7.6 cm or greater of newspaper mulch. Chopped newspaper provided higher tomato yields than shredded newspaper applied at the same rates. Mulches applied at 0, 2, or 4 WAT resulted in weed control similar to the chemical treatment. In North Carolina, mulches applied 2 or 4 WAT resulted in tomato yields similar to the chemical treatment. Shredded and chopped newspaper have potential as a mulching material but may vary in effect in different environments and vegetable crops.

Cover crops aid in reducing precipitation runoff, soil erosion, and N losses in highly sloped, mountainous regions. Corn (Zea mays L.) producers in states with late spring warmup and early winters have limited success when planting cover crops following harvest. Studies were conducted from 1992 through 1995 in southern and northern West Virginia to evaluate the groundcover ability of several late-planted cover crops and their dry weight response to fall N application. In most years, vetch (Vicia villosa Roth cv. Common) and Austrian winter pea (Pisum sativum var. arvense L. Poir cv. Austrian winter) produced the least groundcover and dry matter of all species evaluated. Rye (Secale cereale L. 'Abruzzi' and 'Wheeler') was the most reliable and winter-hardy cover crop, regardless of location. Initial soil nitrate-N concentrations at planting averaged 12 ppm in soils with continuous corn-production and no history of manure application (southern experiment) and 40 ppm in soils with similar rotation and a history of manure application (northern experiment). Nitrogen application did not consistently increase the likelihood of cover crop survival, but increased dry matter for some cover crops on soils with low initial N levels. At the southern location, Abruzzi rye planted alone and common rye in combination with common vetch responded positively to additional N application in 3 out of 3 and 2 out of 3 yr, respectively. 'Pastar' rye (1992-1993), common rye (1993-1994), wheat (Triticum aestivum L.) (1994-1995), and barley (Hordeum vulgare L. 'Barsoy') (1994-1995) also responded positively to N application at the southern location. Cover crops did not respond to additional N application at the northern location on soils high in initial N fertility. Corn producers in mountainous, highly sloped land should consider methods for planting cover crops earlier to ensure plant survival and to protect soil during the winter.

Field trials were conducted from 1991 to 1993 in the northern cotton-producing area of Alabama to evaluate the interaction of various production inputs for pest management and cotton development, maturity, and yield. Two levels of tillage (conventional and no-till), herbicide (1.12 and 2.24 kg ai ha−1fluometuron, preemergence, with post-directed herbicides), insecticide (0.5 and 0.85 kg ai ha−1aldicarb, in-furrow), and fungicide (0.9 kg ai ha−1quintozene plus ethridazole, in-furrow or 0.14 kg ai ha−1metalaxyl, hopper-box) programs were evaluated. The inputs investigated did not interact significantly to change the overall production strategy. Prickly sida required a higher level of herbicide input than did the entireleaf/ivyleaf morningglory complex. Both species were sufficiently controlled using reduced levels of fluometuron without sacrificing yield; however, cultivation was necessary in conventional tillage treatments to maintain control. A postemergence-directed herbicide treatment was also necessary for weed control, regardless of tillage. Decreasing the levels of each input simultaneously did not interact to affect cotton stand, height, early-season thrips counts, cotton maturity, or yield. Cotton was shorter in no-till than conventional plots.

Field experiments were conducted in Alabama from 1992 through 1994 to evaluate the potential of the methyl ester of bensulfuron applied at sublethal rates as a plant growth regulator for reducing plant height and boll rot in cotton. Bensulfuron at 0.017 and 0.034 g ai/ha or mepiquat chloride at 10 g ai/ha was applied POST alone at the pinhead square or early-bloom stage of cotton growth or sequentially at 0.017 followed by (fb) 0.017 g/ha, 0.034 fb 0.034 g/ha of bensulfuron and 5 fb 5, 10 fb 10, 10 fb 20, or 20 fb 20 g/ha of mepiquat chloride. Mepiquat chloride had no effect on yield in 1992 and 1994 but decreased yield when applied sequentially in 1993. Bensulfuron was generally detrimental to first position fruit retention, and it delayed maturity. Treatments that reduced plant height did not reduce boll rot. Bensulfuron treatments that reduced plant height also reduced yield; therefore, the potential for its use as a growth regulator in cotton appears limited.

Imidazolinone herbicides injure currently available commercial field corn cultivars; however, cultivars resistant to these herbicides have been developed. Sicklepod, Texas panicum, and annual morningglory control using AC 263,222 (36 and 72 g ai/ha), imazethapyr (36 and 72 g ai/ha), or nicosulfuron (35 g ai/ha) applied POST at 2, 4, and 6 wk after planting were evaluated in imidazolinone-tolerant corn. Studies were conducted at Attapulgus and Plains, Georgia from 1992 through 1993. Nicosulfuron and AC 263,222 at 72 g/ha controlled Texas panicum at least 87% when applied 2 wk after planting. Imazethapyr did not consistently control Texas panicum or sicklepod, regardless of application rate. AC 263,222 at both rates and nicosulfuron controlled sicklepod at least 86% when applied 2 wk after planting; however, later application or application under dry conditions generally resulted in reduced control. All herbicides controlled the entireleaf and pitted morningglory complex at least 84% when applied 2 wk after planting. Imidazolinone-tolerant corn was tolerant to all herbicides, regardless of rate and timing, and generally yielded greater when weeds were controlled early in the season. Nomenclature : AC 263,222, (±)-2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-methyl- 3-pyridinecarboxylicacid ; imazethapyr, 2-[4,5 -dihydro-4-methyl-4-(1-methylethyl)-5-oxo-lH- imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid; nicosulfuron, 2-[[[[(4,6-dimethoxy-2-pyrimidinyl)- amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-pyridinecarboxamide; entireleaf morningglory, 1pomoea hederacea var. integriuscula Gray # 3 IPOHG; pitted morningglory, Ipomoea lacunosa L. # IPOLA; sicklepod, Senna obtusifolia (L.) Irwin and Barneby # CASOB; Texas panicum, Panicum texanum Buckl. # PANTE; corn, Zea mays L., 'Pioneer 33431R.'

Chlorimuron applied alone and in combination with acifluorfen or thifensulfuron was evaluated for POST control of common lambsquarters, common ragweed, common cocklebur, and a mixture of pitted, ivyleaf, entireleaf, and tall morningglory in soybean. Common cocklebur control was similar with thifensulfuron at 3 and 4 g ae ha−1and with chlorimuron at 7 and 9 g ae ha−1, Common ragweed and morningglory control was greater with chlorimuron while common lambsquarters control was greater with thifensulfuron. Control of all species was good with combinations of chlorimuron at 7 g ha−1plus thifensulfuron at 2 g ha−1or acifluorfen at 140 g ae ha−1and similar to or greater than the control with chlorimuron at 9 g ha−1. Soybean yields with all POST herbicide treatments were equivalent to that of the weed-free check.

We investigate methods for filtering reaction mechanisms in the angular scattering of the state-to-state reaction, H + D(2)(v(i) = 0, j(i) = 0, m(i) = 0) --HD(v(f) = 3, j(f) = 0, m(f) = 0) + D, where v(i), j(i), and m(i) and v(f), j(f), and m(f) are initial and final vibrational, rotational, and helicity quantum numbers, respectively. The input to our filtrations is a new set of accurate quantum scattering matrix elements for total energies in the range 1.52-2.50 eV (in steps of 0.01 eV) and for total angular momentum quantum numbers in the range, 0-40, in steps of unity. We filter reaction mechanisms in both the energy domain and the time domain. The time-domain calculations employ the plane wave packet formulation of time-dependent scattering. The theoretical tools used are nearside-farside (NF) analysis of partial wave series for scattering amplitudes, together with NF local angular momentum (LAM) theory. An energy-domain LAM analysis reveals the existence of an important dynamical feature in the N scattering, a "trench" which bisects the (energy, angle) plane. We use the location of this trench to approximately filter two reaction mechanisms. Transformation to the time domain demonstrates that the two reaction mechanisms correspond to direct and delayed (by about 25 fs) scattering. Further analysis, including filtration in the time domain, shows that the pronounced LAM trench arises from the interference of the energy-domain analogues of the time-direct and time-delayed scattering. Our theory and results provide the first successful demonstration of reaction mechanism filtering carried out directly in the (energy, angle) domain. The calculations and results in this paper extend and complement earlier research reported by Monks, Connor, and Althorpe (Monks, P. D. D.; Connor, J. N. L.; Althorpe, S. C. J. Phys. Chem. A 2006, 110, 741; J. Phys. Chem. A 2007, 111, 10302).

Chlorimuron applied postemergence at 2.2, 4.4, 8.8, 18, and 35 g ai/ha to cotton at either the 4-leaf, pinhead-square, first-bloom, or full-bloom growth stage was evaluated for potential as a plant growth regulator. Chlorimuron did not reduce boils per plant at any rate or time of application, but the proportion of open to closed boils decreased as rate increased. Seed cotton yields decreased with increasing chlorimuron rate and cotton age. The use of chlorimuron as a plant growth regulator for cotton appears limited. Nomenclature: Chlorimuron, 2-[[[[(4-chloro-6methoxy-2-pyrimidinyl)axniino]carbonyl]aniino]sulfonyl]benzoic acid; cotton, Gossypium hirsutum L. 'DPL 50' #3 GOSHI. Additional index words: Plant growth regulator, PGR, sulfonylurea, Gossypium hirsutum, GOSHI.

Nearside-farside (NF) theory, originally developed in the energy domain for the time-independent description of molecular collisions and chemical reactions, is applied to the plane wave packet (PWP) formulation of time-dependent scattering. The NF theory decomposes the partial wave series representation for the time-dependent PWP scattering amplitude into two time-dependent subamplitudes: one N, the other F. In addition, NF local angular momentum (LAM) theory is applied to the PWP scattering amplitude. The novel concept of a cumulative time-evolving differential cross section is introduced, in which the upper infinite time limit of a half-Fourier transform is replaced by a finite time. In a similar way, a cumulative energy-evolving angular distribution is defined. Application is made to the state-to-state reaction, H + D2(v(i) = 0, j(i) = 0) --> HD(v(f) = 3, j(f) = 0) + D, where v(i), j(i) and v(f), j(f) are vibrational and rotational quantum numbers for the initial and final states, respectively. This reaction exhibits time-direct and time-delayed (by about 25 fs) collision mechanisms. It is shown that the direct-time mechanism is N dominant scattering, whereas the time-delayed mechanism exhibits characteristics of NF interference. The NF and LAM theories provide valuable insights into the time-dependent properties of a reaction, as do snapshots from a movie of the cumulative time-evolving differential cross section.

The technique of local angular momentum-local impact parameter (LAM-LIP) analysis has recently been shown to provide valuable dynamical information on the angular scattering of chemical reactions under semiclassical conditions. The LAM-LIP technique exploits a nearside-farside (NF) decomposition of the scattering amplitude, which is assumed to be a Legendre partial wave series. In this paper, we derive the "fundamental NF LAM identity," which relates the full LAM to the NF LAMs (there is a similar identity for the LIP case). Two derivations are presented. The first uses complex variable techniques, while the second exploits an analogy between the motion of the scattering amplitude in the Argand plane with changing angle and the classical mechanical motion of a particle in a plane with changing time. Alternative forms of the fundamental LAM-LIP identity are described, one of which gives rise to a CLAM-CLIP plot, where CLAM denotes (Cross section) x LAM and CLIP denotes (Cross section) x LIP. Applications of the NF LAM theory, together with CLAM plots, are reported for state-to-state transitions of the benchmark reactions F+H2--FH+H, H+D2--HD+D, and Cl+HCl--ClH+Cl, using as input both numerical and parametrized scattering matrix elements. We use the fundamental LAM identity to explain the important empirical observation that a NF cross section analysis and a NF LAM analysis provide consistent (and complementary) information on the dynamics of chemical reactions.

A procedure for the determination of iodide in charcoals impregnated with potassium iodide is described. An aqueous extract is prepared and the iodide ion concentration in this extract (up to 4 × 10–3 mol dm–3) is determined by injection into a water stream that is merged with an aqueous solution containing potassium iodate and sulfuric acid, followed by absorptiometric measurement at 460 nm. The analysis is simple and rapid, with a limit of detection of 6 × 10–5 mol dm–3 iodide and a relative standard deviation (n= 10) of 1.2% for 1 × 10–3 mol dm–3 iodide. The procedure was used to measure the levels and the distribution of potassium iodide in impregnated charcoals. The flow method is discussed with reference to the chemistry of elementary iodine in aqueous solution.