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A Co(II) PNNH pincer catalyst system for the highly E-selective transfer-semihydrogenation of internal alkynes using ammonia borane and MeOH as the hydrogen source is described. The reaction is proposed to occur via the Co(ii) oxidation state.

Catalytic dehydropolymerisation of methylamine borane using the boryl pincer complex [(PBP)Ir(H)(Cl)]/NaOtBu proceeds via an unusual highly fluxional Ir tetrahydride.

Globally, fisheries have been the site of multiple documented outbreaks of COVID-19. Existing studies point to the threat posed by the pandemic to livelihoods and health among migrant industrial fishery workers, small-scale fish harvesters, and fishing communities. They show the pandemic enhanced safety, economic, social and political layers of vulnerability in fisheries, while also showcasing examples of resilience. Case studies of COVID-19 response provide an opportunity to explore how existing organizational structures, leadership and networks in fisheries can enable the rapid co-development of customized strategies for fishing safely during large-scale global disruptions such as pandemics. This article contributes to our understanding of governance and fishing safety in small-scale fisheries during the early pandemic, examining the response of small-scale fisheries in the Canadian province of Newfoundland and Labrador. These seasonal fisheries successfully opened with regulator approval after a short delay and operated without documented COVID-19 outbreaks during 2020. Findings draw from key informant interviews with a safety sector association and union leader, complemented with insights from an anonymous online survey of small-scale harvesters. Interviews capture the organizational processes and resources mobilized to rapidly co-develop the COVID-19 Safe Work Practice Guideline. Online survey findings indicate that fifty-nine percent of respondents (crew and skippers) had no COVID-19-related concerns while fishing in 2020; older harvesters and owner-operators were significantly more likely to indicate concerns. When asked about the relative practicality of listed COVID-19 precautions, respondents commonly identified sanitization, reduced interactions with shore workers, social distancing, protection equipment, modifications to eating/rest areas, and reduced crew as impractical. These assessments are generally consistent with those of the interviewed leaders and the Guideline approach. This suggests the co-developed Guideline provided tailored and practical COVID-19 prevention strategies. Pre-existing governance structures and networks can help address small-scale fisheries vulnerabilities to pandemics by supporting co-development of organizational resources and evidence-informed prevention strategies.

Chemoselective semihydrogenation of alkynes to alkenes with E- or Z-stereoselectivity is among the most important transformations in the synthesis of highly functional organic building blocks. Use of hydrogen transfer reagents instead of gaseous hydrogen represents a viable, safe alternative in many cases. This review summarises recent developments in the field using homogeneous, molecularly defined catalyst systems with focus on hydrogen sources and mechanistic aspects of the respective systems.

Many fisheries managers and neoliberal fisheries economists promote Individual Transferable Quotas (ITQs) as a solution to the race for fish which can cause rent dissipation under competitive quota or open access fisheries. These actors consider the Canadian Pacific halibut ITQ fishery an example of successful achievement of these objectives. However, critics note the weak performance of this management model in distribution of benefits, increased capital costs to fishermen, deteriorating safety conditions, reductions in crew income and barriers to entry. They point to the layup system which successfully managed effort in the Pacific halibut fishery for four decades prior to the introduction of ITQs. A system similar to the layup has been used for Atlantic halibut since 2013, initiated by the Fish Food and Allied Workers (FFAW) representing owner‐operator license holders in the halibut fishery off the coast of western Newfoundland and southern Labrador. The FFAW rejected the two halibut management plan options presented to them by Fisheries and Oceans Canada: the status quo (a competitive 12‐hr “derby” fishery) or IQs, likely leading to ITQs. Instead, the FFAW worked with license holders to develop a management plan that required harvesters to choose between different fishing periods that spread fishing opportunities over time. This approach improved conservation results, delivered strong economic returns, distributed benefits widely to active fishermen, and allowed an even flow into the market. The authors consider the advantages of these Canadian east and west coast halibut co‐management systems and their broader application.

Correction for ‘Catalytic and mechanistic studies of a highly active and E-selective Co(ii) PNNH pincer catalyst system for transfer-semihydrogenation of internal alkynes’ by David Decker et al., Inorg. Chem. Front., 2022, DOI: 10.1039/d1qi00998b.

Six new 8-styryl-substituted coralyne derivatives 4a–f were synthesized from coralyne (2) by a base catalysed Knoevenagel type reaction. It was shown by photometric and fluorimetric titrations of double stranded and quadruplex DNA to 4b–d as well as by fluorimetric DNA denaturation experiments that these ligands bind to DNA with different binding modes at varying ligand-DNA ratios (LDR). Specifically, the addition of DNA caused initially a hypochromic effect in absorbance and, at a particular LDR, the development of a new red shifted absorption band with a hyperchromic effect. Furthermore, 4b–d induced a significant and selective stabilization of quadruplex DNA towards unfolding (ΔTm = 31.6–32.9 °C at LDR = 5), which is even more pronounced as compared to the parent compound coralyne (2). Most notably, the addition of DNA to the dimethylamino-substituted derivative 4b leads to a new, strongly red-shifted emission band at 695 nm. Hence, this derivative is a fluorescent probe that changes its fluorescence colour from green to red in the presence of DNA and even allows the fluorimetric analysis of living cells by staining of the nucleoli.

Gordon Jacob's (1895-1984) Old Wine in New Bottles (1959) and More Old Wine in New Bottles (1977) are regularly performed works within the canon of chamber wind repertoire. Composed for thirteen instruments, the original work and its sequel are a reflection of Jacob's refined compositional style, which emphasizes unique textures, clear formal structures, and recognizable folk melodies. Gordon Jacob was a British composer from Upper Norwood, London. During his youth he studied piano and took up percussion in order to join his school band and orchestra. After serving in the First World War, Jacob enrolled at the Royal College of Music (RCM) where he studied composition with Ralph Vaughan Williams and Sir Charles Villiers Stanford. Shortly after graduation, he was offered an instructor position at the RCM. He remained on faculty for forty-two years, instructing many musicians who would later become internationally recognized composers, including Imogen Holst, Sir Malcolm Arnold, and Philip Cannon. As a composer, he has approximately four-hundred works to his name and is best known in the area of wind band for his compositions William Byrd Suite (1922), An Original Suite (1928), Music for a Festival (1951), Flag of Stars (1954), and Giles Farnaby Suite (1967). This study is an analysis of and conductor's guide for two of Jacob's chamber works that have not been the subject of any previous scholarly publications. The opening chapters include a brief biography of the composer emphasizing the musical developments of his youth, his achievements as an educator, and a discussion of his compositional style. The following two chapters delve into Old Wine in New Bottles and More Old Wine in New Bottles, respectively. Each includes an original historical account of the piece, discussion of the preexisting folk music, theoretical analysis, and suggestions for the conductor. This study is intended to assist conductors in the score-study and preparation process, leading to more effective rehearsals and informed performances.

Coastal fisheries play a vital role in the marine sector of the Nordic countries and serves as a backbone of the economy of many smaller coastal communities. The coastal fleets usually have a big p ...

Cationic biaryl derivatives were synthesized by Suzuki–Miyaura coupling of 3-bromonaphtho[1,2-b]quinolizinium bromide with arylboronic acids. The resulting cationic biaryl derivatives exhibit pronounced fluorosolvatochromic properties. First photophysical studies in different solvents showed that the emission energy of the biaryl derivatives decreases with increasing solvent polarity. This red-shifted emission in polar solvents is explained by a charge shift (CS) in the excited state and subsequent solvent relaxation. Furthermore, the polarity of protic polar and aprotic polar solvents affects the emission energy to different extent, which indicates a major influence of hydrogen bonding on the stabilization of the ground and excited states.

Cationic biaryl derivatives were synthesized by Suzuki–Miyaura coupling of 3-bromonaphtho[1,2-b]quinolizinium bromide with arylboronic acids. The resulting cationic biaryl derivatives exhibit pronounced fluorosolvatochromic properties. First photophysical studies in different solvents showed that the emission energy of the biaryl derivatives decreases with increasing solvent polarity. This red-shifted emission in polar solvents is explained by a charge shift (CS) in the excited state and subsequent solvent relaxation. Furthermore, the polarity of protic polar and aprotic polar solvents affects the emission energy to different extent, which indicates a major influence of hydrogen bonding on the stabilization of the ground and excited states.

Background and Purpose— The ABC/2 score estimates intracerebral hemorrhage (ICH) volume, yet validations have been limited by small samples and inappropriate outcome measures. We determined accuracy of the ABC/2 score calculated at a specialized reading center (RC-ABC) or local site (site-ABC) versus the reference-standard computed tomography–based planimetry (CTP). Methods— In Minimally Invasive Surgery Plus Recombinant Tissue-Type Plasminogen Activator for Intracerebral Hemorrhage Evacuation-II (MISTIE-II), Clot Lysis Evaluation of Accelerated Resolution of Intraventricular Hemorrhage (CLEAR-IVH) and CLEAR-III trials. ICH volume was prospectively calculated by CTP, RC-ABC, and site-ABC. Agreement between CTP and ABC/2 was defined as an absolute difference up to 5 mL and relative difference within 20%. Determinants of ABC/2 accuracy were assessed by logistic regression. Results— In 4369 scans from 507 patients, CTP was more strongly correlated with RC-ABC ( r 2 =0.93) than with site-ABC ( r 2 =0.87). Although RC-ABC overestimated CTP-based volume on average (RC-ABC, 15.2 cm 3 ; CTP, 12.7 cm3), agreement was reasonable when categorized into mild, moderate, and severe ICH (κ=0.75; P Conclusions— ABC/2 scores at local or central sites are sufficiently accurate to categorize ICH volume and assess eligibility for the CLEAR-III and MISTIE III studies and moderately accurate for change in ICH volume. However, accuracy decreases with large, irregular, or lobar clots. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: MISTIE-II NCT00224770; CLEAR-III NCT00784134.

BACKGROUND High-flow intracranial arteriovenous (AV) fistulas associated with giant varices are rare lesions. These varices can present with symptoms from mass effect, spontaneous hemorrhage, and seizures to cardiac failure. Direct AV fistulas of the posterior inferior cerebellar artery (PICA) are extremely rare lesions, with only two cases reported in the literature. CASE DESCRIPTION The authors present an unusual case of a 25-year-old male with a direct AV fistula of the PICA that resulted from a fracture of the occipital condyle. This high-flow AV fistula drained into a giant varix of the vein of the lateral recess that compressed the brainstem, resulting in a Wallenberg syndrome. The patient underwent embolization of the proximal PICA feeding the fistula with a Guglielmi detachable coil (GDC), which resulted in thrombosis of the varix. A postembolization angiogram showed occlusion of the PICA AV fistula and draining varix. A computed tomography (CT) scan performed at a 10-month follow-up visit showed dramatic decompression of the brainstem. Although the patient continued to have some sensory changes secondary to Wallenberg syndrome, he was otherwise doing well neurologically. CONCLUSION The treatment of this lesion is difficult because of its location near the brainstem. Postocclusion edema or hemorrhage can result in mass effect and life-threatening brainstem compression. Our patient, whose AV fistula was caused by trauma, was treated effectively with GDC embolization.

The authors reviewed changes in the initial clinical presentation, management techniques, and patterns of disease recurrence over time (1981-1996) in patients with breast carcinoma treated with breast-conserving therapy (BCT) at a single institution. The goals of the current study were to determine the frequency and use of optimal local and systemic therapy techniques and to evaluate the impact of these changes on treatment efficacy.Six hundred seven patients with American Joint Committee on Cancer Stage I or II invasive breast carcinomas treated with BCT at William Beaumont Hospital (Royal Oak, MI) constituted the study population. All patients received at least an excisional biopsy of the primary tumor, an axillary lymph node staging procedure, and postoperative radiotherapy (RT) (a median tumor bed dose of 61 Gray [Gy] was administered). All sides were reviewed by one pathologist. Numerous clinicopathologic and treatment-related factors were analyzed to monitor changes that occurred over time. Changes in patterns of disease recurrence and treatment efficacy over time also were analyzed.Over the time period analyzed, changes at initial presentation included an increase in the mean age at diagnosis (age 56.1 years vs. 61.4 years; P0.001), a decrease in the number of patients with clinically palpable tumors (78% vs. 36%; P0.001), a decrease in the mean tumor size (2.2 cm vs. 1.6 cm; P0.001), but no change in the percentage of patients with negative lymph nodes (79% vs. 78%; P = 0.83). No differences over time were observed in mean tumor grade (2.0 vs. 1.9; P = 0.2) or the presence of angiolymphatic invasion (27% vs. 26%; P = 0.25). Changes in surgical management and pathologic assessment included the more frequent use of reexcision (46% vs. 81%; P0.001), larger mean total volumes of breast tissue specimens excised (115 cm3 vs. 189 cm3; P = 0.001), a larger percentage of patients with final negative surgical margins (74% vs. 97%; P0.001), and a small increase in the mean number of lymph nodes excised (13.8 lymph nodes vs. 14.1 lymph nodes; P = 0.01). The only other significant change in the pathologic management of patients over time included a doubling in the mean number of slides examined (10.6 slides vs. 21.1 slides; P0.001). Changes in adjuvant local and systemic therapy included an increase in the percentage of patients treated with60 Gy to the tumor bed (66% vs. 95%; P0.001), a doubling in the mean number of days from the last surgery to the start of RT (24 days vs. 50 days; P0.001), and a decrease in the use of regional lymph node RT (24% vs. 8%; P0.001). The use of adjuvant tamoxifen increased from 10% to 61% (P0.001). Finally, improvements were observed in the 5-year and 12-year actuarial rates of local disease recurrence (8% vs. 1% and 21% vs. 9%, respectively; P = 0.001) and distant metastases (12% vs. 4% and 22% vs. 9%, respectively; P = 0.006). No changes in the mean number of years to ipsilateral (6.5 years vs. 6.4 years; P = 0.59) or distant disease recurrence (4.6 years vs. 3.8 years; P = 0.73) were observed.The impact of screening mammography and substantial changes in surgical, pathologic, RT, and systemic therapy recommendations were observed over time in the study population. These changes were associated with improvements in 5-year and 12-year local and distant control rates and suggested that improvements in outcome can be realized through adherence to best practice guidelines and continuous monitoring of treatment outcome data.

OBJECTIVEAnterior cranial base tumors are surgically resected with combined craniofacial approaches that frequently involve disfiguring facial incisions and facial osteotomies. The authors outline three operative zones of the anterior cranial base and paranasal sinuses in which tumors can be resected with three standard surgical approaches that minimize transfacial incisions and extensive facial osteotomies.METHODSThe zones were defined by performing dissections on 10 cadaveric heads and by evaluating radiographic images of patients with anterior cranial base tumors. The three approaches performed on each cadaver were transbasal, transmaxillary, and extended transsphenoidal.RESULTSThree zones of approach were defined for accessing tumors of the anterior cranial base, nasal cavity, and paranasal sinuses. Zone 1 is exposed by the transbasal approach, which is limited anteriorly by the supraorbital rim, posteriorly by the optic chiasm and clivus, inferiorly by the palate, and laterally by the medial orbital walls. This approach allows access to the entire anterior cranial base, nasal cavity, and the majority of maxillary sinuses. The limitation imposed by the orbits results in a blind spot in the superolateral extent of the maxillary sinus. Zone 2 is exposed by a sublabial maxillotomy approach and accesses the entire maxillary sinus, including the superolateral blind spot and the ipsilateral anterior cavernous sinus. However, access to the anterior cranial base is limited. Zone 3 is exposed by the transsphenoidal approach. This approach accesses the midline structures but is limited by the lateral nasal walls and intracavernous carotid arteries. An extended transsphenoidal approach allows further exposure to the anterior cranial base, clivus, or cavernous sinuses. The use of the endoscope facilitates tumor resection in the nasal cavity and paranasal sinuses.CONCLUSIONThe operative zones outlined offer minimally invasive craniofacial approaches to accessing lesions of the anterior cranial base and paranasal sinuses, obviating facial incisions and facial osteotomies. Case illustrations demonstrating the approach selection paradigm are presented.

Reports of acute onset of Guillain-Barre syndrome (GBS) after epidural anesthesia/analgesia after labor and cesarean delivery has raised concern of a correlation between GBS and the use of neuraxial anesthesia. We present a patient who developed bilateral lower extremity weakness and paraparesis within hours after removal of an epidural catheter for cesarean delivery. The clinical diagnosis was highly suggestive for GBS after magnetic resonance imaging, cerebrospinal fluid findings, electromyogram, and nerve conduction studies. We discuss the pathophysiological mechanisms suggested in previous case reports and describe the relationship between epidural analgesia and GBS.

Purpose In this study, we compare symptom response and times to response among patients with breast cancer who were assigned to either a cognitive behavioral Nurse-Administered Symptom Management intervention or an Automated Telephone Symptom Management (ATSM) intervention. Patients and Methods Patients with breast cancer were identified from a larger trial. Baseline equivalence existed between arms, and there was no differential attrition by arm. Anchor-based definition of response using mild, moderate, and severe categories of symptom severity were used. Responses and times to response for 15 symptoms were investigated in relation to trial arm, comorbid conditions, treatment protocols, and metastatic versus localized disease. Results The ATSM arm was more effective among patents with metastatic disease. Compared with patients receiving combination chemotherapy protocols, those treated with single agents had greater response and shorter time to response. Conclusion An educational information intervention delivered via an automated voice response system that assesses symptoms and refers patients to a Symptom Management Guide is more effective than a complex cognitive behavioral approach in terms of producing greater symptom responses in shorter time intervals among patients with metastatic disease.

The results of a randomized controlled trial that tested the effects of eight-week, six-contact multi-dimensional interactive interventions for symptom management are presented. Four hundred and thirty-five cancer patients with solid tumors undergoing chemotherapy were randomized to receive either nurse-assisted symptom management (NASM) or automated telephone symptom management (ATSM). A prior trial established the effectiveness of NASM compared with conventional care. Seventeen symptoms commonly experienced by patients undergoing chemotherapy were rated on a scale from 0 to 10 and were evaluated at baseline, at each of the six intervention contacts and post-intervention observation at 10 weeks. Both groups achieved significant reduction in symptom severity over baseline, and there was no difference between groups on symptom severity at 10 weeks. Randomization accounted for possible reductions in severity due to response shifts. Severity of symptoms reported by patients at each of the six intervention contacts was measured using a Rasch model. Symptom pattern was different for lung and non-lung cancer patients, and they were analyzed separately. Longitudinal analyses revealed that lung cancer patients with greater symptom severity withdrew from later intervention contacts of the ATSM. The results suggest that both NASM and ATSM achieved a clinically significant reduction in symptom severity. The NASM may be more effective than ATSM in retaining lung cancer patients in the intervention. Further testing of ATSM supplemented by NASM for patients with severe symptoms is warranted.

We evaluated the bird repellency of ReJeX-iT® AG-36 which contains the active ingredient methyl anthranilate (MA). In a 14-day field trial in Michigan, MA applied at 16.1 kg ha−1 did not reduce bird damage overall, but did appear to offer some protection from 3 to 10 days post-treatment. After 10 days, however, bird damage more than doubled. In Florida, we applied MA at a rate of 32 kg ha−1 and then presented the fruit to individually caged cedar waxwings (Bombycilla cedrorum). Berry consumption did not differ between treatment and control groups, but consumption of berries 72 h post-spray exceeded that of 24 h post-spray.

SUMMARY Economically viable natural gas production from the low permeability Mesaverde Formation in the Piceance Basin, Colorado requires the presence of an intense set of open natural fractures. Establishing the regional presence and specific location of such natural fractures is the highest priority exploration goal in the Piceance and other western U.S. tight, gas-centered basins. Recently, Advanced Resources International, Inc. (ARI) completed a field program at Rulison, Piceance Basin, to test and demonstrate the use of advanced seismic methods to locate and characterize natural fractures. This project, conducted jointly with Barrett Resources and supported by the USDOE/FETC, began with a comprehensive review of the tectonic history, state of stress and fracture genesis of the basin. A high resolution aeromagnetic survey, interpreted satellite and SLAR imagery, and 400 line miles of 2-D seismic provided the foundation for the structural interpretation. The central feature of the program was the 4.5 square mile multi-azimuth 3-D seismic P-wave survey to locate natural fracture anomalies. The interpreted seismic attributes are being tested against a control data set of 27 wells. Additional wells are currently being drilled at Rulison, on close 40 acre spacings, to establish the productivity from the seismically observed fracture anomalies. A similar regional prospecting and seismic program is being considered for another part of the basin. The preliminary results indicate that detailed mapping of fault geometries and use of azimuthally defined seismic attributes exhibit close correlation with high productivity gas wells. The performance of the ten new wells, being drilled in the seismic grid in late 1996 and early 1997, will help demonstrate the reliability of this natural fracture detection and mapping

This paper describes an approach to the classification of signals, based on the integration of Genetic Algorithms with Neural Network learning algorithms. First, a Genetic Algorithm is applied to the off-line task of selecting a minimal feature set, for later use in the classifier system. The second use of the Genetic Algorithm, in conjunction with the Backpropagation algorithm, is improvement in the training of multi-layer network weights. We demonstrate the effectiveness of this approach on a complex target classification task, and the promising result is generally applicable to a wide spectrum of signal classification tasks. By integrating the Genetic Algorithm with various Neural Network algorithms, we demonstrate a high degree of synergy which allows improved learning and performance, in both the extraction of key data features, and the classification of individuals based on these features.

Natural fracture intensity and diversity of orientation are requirements for commercial production from tight gas reservoirs. The ability to find and define these open natural fractures in advance of drilling represents the major challenge for continued development of these low permeability reservoirs. Since tectonic fractures are frequently caused by subtle basement structures, the Naturally Fractured Tight Gas Reservoir Optimization project is focused on techniques that can identify basement features and thereby locate the overlying fractured reservoirs.

Eight laser dyes emitting in the spectral region from 550 to 915 nm were investigated to determine their power scalability under excitation by Q‐switched frequency‐doubled Nd : YAG lasers possessing up to 480 mJ pulse energy at 10 Hz pulse repetition frequency (PRF). Conversion efficiencies for some dyes begin to be limited at pump‐power densities as low as 14 MW/cm2 due to excited‐state absorption of the pumping radiation. The dependence on resonator length of dye spectral emission, conversion efficiency, and temporal modulation are reported. Divergence of the beam emerging from the dye laser was found to be adversely affected by measures taken to avoid output power saturation at high pump‐power densities.

[Co{OC(C 6 H 11 ) 3 } 2 ] 2 •CH 3 OH•1/2C 6 H 12 •THF et [Co(OCPh 3 ) 2 ] 2 • n-C 6 H 14 cristallisent dans le systeme triclinique. Groupe d'espace P1 et leur structure est affinee respectivement jusqu'a R=0,076 et R=0,072. [Co(OSiPh 3 ) 2 (THF)] 2 cristallise dans le systeme monoclinique, groupe d'espace P2 1 /n avec R=0,056 [Co(OCPh 3 ) 2 (THF) 2 ] cristallise dans le systeme monoclinique, C2/c, avec R=0,054

The development of a high peak and average power stimulated Raman scattering (SRS) source with a dye amplifier is described. Emission from 505 to 771 nm is obtained using 532‐nm radiation from a frequency‐doubled Nd : YAG laser as the optical pump. Dimethyl sulfoxide (DMSO) is found to be a very efficient SRS medium, and produces 40% energy conversion from 532 to 630 nm at 10 pulses/sec. Use of a dye amplifier increases energy conversion efficiency to 60%. Mixtures of DMSO and d‐DMSO are found to emit the I and II Stokes lines of each material, plus a ’’mixed’’ mode line at 727 nm. SRS is also shown to be a limiting phenomenon in the power scaling of laser‐pumped dye lasers.

Efficient near‐infrared dye laser emission has been achieved in the 838–923‐nm range by use of a frequency‐doubled Nd:YAG laser as the optical pump for various polymethine dyes. Experimental evidence of 1064‐nm quenching of the dye laser emission is reported. Strong excited state absorption (ESA) effects are observed for the dye IR‐140 at the 532‐nm pump wavelength. This excited state absorption results in an experimentally determined optimum pump power density of 50–60 MW/cm2 for maximum dye laser efficiency. Such excited state absorption may thus be a limiting factor in the power scaling of pulsed dye lasers.

The 5106‐A output of a 250‐mW copper‐vapor laser has been used to obtain laser action in a Rhodamine 6G dye laser. The high gain of such a copper‐vapor laser pumped dye solution has been demonstrated by amplifying the 5782‐A output of the same copper‐vapor laser.