bluuebunny/crossref_metadata_2025 huggingface dataset:
Total Synthesis of Parvineostemonine by Structure Pattern Recognition: A Unified Approach to Stemona and Sarpagine Alkaloids
Authors: Gerlinger Christa K. G. , Krüger Sebastian , Gaich Tanja
Published: January 2018

Through structure pattern recognition based total synthesis we designed a synthesis in which two biogenetically unrelated natural product families (Stemona‐ and Sarpagine alkaloids) share 50 % of their synthetic sequence. In this report, the efficiency of such a strategic approach is demonstrated in the total synthesis of the Stemona alkaloid parvineostemonine, proceeding through a privileged intermediate that we have previously transformed into biogenetically completely unrelated Sarpagine alkaloids. In addition, we capitalized on the symmetry properties of the privileged intermediate, which was obtained as two regioisomers. After their separation by column chromatography the two regioisomers were converted to the corresponding pair of enantiomers by one transformation. To the best of our knowledge, this feature (conversion of regioisomers to enantiomers) has never been applied to natural product synthesis, and proved to be very valuable, since it allowed to obtain both optical antipodes of parvineostemonine in a single synthetic campaign. This not only enabled the determination of the previously undisclosed absolute configuration of the natural product, but gave 60–200 mg amounts of both enantiomers of the natural product.
Conformation change of hornet silk proteins in the solid phase in response to external stimulation
Authors: Kuroda Reiko , Kameda Tsunenori
Published: January 2018

Hornet silks adopt a variety of morphology such as fibers, sponge, films, and gels depending on the preparation methods. We have studied the conformation change of hornet silk proteins (Vespa mandarina) as regenerated films, using chiroptical spectrophotometer universal chiroptical spectrophotometer 1, which can measure true circular dichroism spectra without artifact signals that are intrinsic to solid‐state samples. The spectra showed that the proteins in films alter the conformation rapidly from the α‐helix to the coiled coil and then to a β‐sheet structure in response to heat/moisture treatment, but the transformation stopped at the coiled coil state when the sample was soaked in EtOH/water solution. Water is required for the α‐helix to the coiled coil transition, and extra energy is required for the further transition to a β‐sheet structure. This is the first successful circular dichroism study of fibril silk proteins to follow the conformation changes in the solid state. This work shows that proteins can undergo conformational changes easily even in the solid phase in response to external stimuli, and this can be traced by solid‐phase‐feasible chiroptical spectrophotometers. Application of unnatural stress to proteins gives valuable insights into their structure and characteristics.
Enzymatic decolourization of water using loofa sponge as cellular carrier: Immobilization and dye degradation performance
Authors: Mohammed Iman , Werner Anett , Schubert Markus , Hampel Uwe
Published: January 2018

In recent years, strong efforts have been made to develop sustainable biocatalytic decolourization processes for dye‐polluted water. In particular, dye‐oxidizing laccase enzymes immobilized on suitable carriers are promising candidates, and can be reused as long as the activity is sufficiently high.

In this work, we propose, for the first time, a new methodology to immobilize laccase from Trametes hirsute on a naturally‐grown and decomposable cellular loofa sponge carrier and assess the capability to degrade dye‐polluted water. High immobilization activity is achieved and about 70 % residual activity remains after 8 cycles. Additionally, we determined homogenous and heterogeneous kinetic parameters for free and immobilized enzymes. The results reveal a four times higher Michaelis‐Menten constant of the laccase immobilized on the loofa due to mass transfer and mixing limitations in a packed bed bio‐reactor.

The response surface methodology was applied to identify favourable operating conditions. In particular, dye concentration and treatment time determine the decolourization performance, while mixing velocity has only a minor effect. Eventually, the results demonstrated a remarkable dye removal capability with shorter treatment time compared to the previous studies on immobilized laccase reported in the literature.
On Equilibrium Shape of Charged Flat Drops
Authors: Muratov Cyrill B. , Novaga Matteo , Ruffini Berardo
Published: January 2018

The equilibrium shapes of two‐dimensional charged, perfectly conducting liquid drops are governed by a geometric variational problem that involves a perimeter term modeling line tension and a capacitary term modeling Coulombic repulsion. Here we give a complete explicit solution to this variational problem. Namely, we show that at fixed total charge a ball of a particular radius is the unique global minimizer among all sufficiently regular sets in the plane. For sets whose area is also fixed, we show that balls are the only minimizers if the charge is less than or equal to a critical charge, while for larger charge minimizers do not exist. Analogous results hold for drops whose potential, rather than charge, is fixed. © 2018 Wiley Periodicals, Inc.
Irish clinical and counselling psychologists' experiences and views of mandatory personal therapy during training: A polarisation of ethical concerns
Authors: McMahon Aisling
Published: January 2018

Although there have been some recent changes in Ireland, the practice of mandating personal therapy during training has traditionally differed between counselling and clinical psychologists. Irish psychologists (n = 258: 170 clinical, 88 counselling) took part in a survey study of experiences and views regarding this practice. Counselling psychologists reported higher rates of lifetime and current attendance at personal therapy compared to clinical psychologists, and nearly all had experienced mandated personal therapy compared to a minority of the clinical group. However, the clinical psychologists had a high rate of attendance at personal therapy compared to that reported for their British peers, indicating a high regard for personal therapy amongst Irish clinicians despite the absence of a training mandate. Five factors were found to be independent predictors of agreement with mandating personal therapy during training—lifetime experience of personal therapy, being a counselling psychologist, experience of mandated therapy, being more recently qualified, and longer attendance at personal therapy. Thematic analysis of the psychologists' open responses regarding mandated therapy indicated that the majority believed that personal therapy was an important part of ethical, effective practice, and valuable in enhancing self‐awareness and learning from the client experience. Ethical concerns about a mandate were polarised between the two psychology specialisms, more counselling psychologists emphasising the dangers and questionable efficacy of psychologists practising psychotherapy without personal therapy experience, and more clinical psychologists questioning the efficacy and ethics of imposing a mandate on trainees. Recommendations are made regarding this issue for trainers of both specialisms.
Pediatric Drug Development: Outlook for Science‐Based Innovation
Authors: Green Dionna J. , Zineh Issam , Burckart Gilbert J.
Published: January 2018

There has been significant progress in pediatric drug development during the past 15 years. Results from 1,200 pediatric studies have been submitted to the US Food and Drug Administration (FDA). Over 700 drug labels have been revised with information to guide pediatric use. Two international pediatric trial networks have been established.1,2 The failure rate for pediatric efficacy trials has fallen from over 40%3 to about 20%. Taken together, the outlook for pediatric drug development is positive.
Public Health Policy Strategies to Address the Opioid Epidemic
Authors: Holton Dwight , White Elizabeth , McCarty Dennis
Published: January 2018

Public health policy responses to the opioid epidemic require addressing both opioid supply and opioid demand. The growth in prescriptions of opioid analgesics, for example, is associated with escalating opioid overdose fatalities.1 Enhanced access to opioid agonist treatment, conversely, is required to curb demands driven by opioid use disorders. Oregon's multidimensional approaches toward opioid misuse and abuse achieved 20% reductions in opioid prescribing and a 30% reduction in the opioid overdose fatality rate.
A provably secure code‐based short signature scheme and its nontransferable variant
Authors: Rajabzadeh Asaar Maryam , Salmasizadeh Mahmoud , Aref Mohammad Reza
Published: January 2018

Signatures with partially message recovery in which some parts of messages are not transmitted with signatures to make them shorter are helpful where bandwidth is one of the critical concern. This primitive is especially used for signing short messages in applications such as time stamping, certified email services, and identity‐based cryptosystems. In this paper, to have quantum‐attack‐resistant short signatures, the first signature scheme with partially message recovery based on coding theory is presented. Next, it is shown that the proposal is secure under Goppa Parametrized Bounded Decoding and the Goppa Code Distinguishing assumptions in the random oracle model. Relying on the partially message recovery property, the proposal is shorter than Dallot signature scheme, the only provably secure and practical code‐based signature scheme, while it preserves Dallot signature efficiency. We should highlight that our scheme can be used as a building block to construct short code‐based signature schemes with special properties. To show this, we present a provably secure short designated verifier signature scheme, a nontransferable form of short signatures, which is used in electronic voting and deniable authentication protocols.
Dynamical facilitation of the ideal free distribution in nonideal populations
Authors: Street Garrett M. , Erovenko Igor V. , Rowell Jonathan T.
Published: January 2018

The ideal free distribution (IFD) requires that individuals can accurately perceive density‐dependent habitat quality, while failure to discern quality differences below a given perception threshold results in distributions approaching spatial uniformity. Here, we investigate the role of population growth in restoring a nonideal population to the IFD. We place a simple model of discrete patch choice under limits to the resolution by which patch quality is perceived and include population growth driven by that underlying quality. Our model follows the population's distribution through both breeding and dispersal seasons when perception limits differ in their likely influence. We demonstrate that populations of perception limited movers can approximate an IFD provided sufficient population growth; however, the emergent IFD would be temporally inconstant and correspond to reproductive events. The time to emergence of the IFD during breeding is shorter under exponential growth than under logistic growth. The IFD during early colonization of a community persists longer when more patches are available to individuals. As the population matures and dispersal becomes increasingly random, there is an oscillation in the observance of IFD, with peaks most closely approximating the IFD occurring immediately after reproductive events, and higher reproductive rates producing distributions closer to the IFD.
Fundamental contradictions among observational and experimental estimates of non‐trophic species interactions
Authors: Barner Allison K. , Coblentz Kyle E. , Hacker Sally D. , Menge Bruce A.
Published: January 2018

The difficulty of experimentally quantifying non‐trophic species interactions has long troubled ecologists. Increasingly, a new application of the classic “checkerboard distribution” approach is used to infer interactions by examining the pairwise frequency at which species are found to spatially co‐occur. However, the link between spatial associations, as estimated from observational co‐occurrence, and species interactions has not been tested. Here we used nine common statistical methods to estimate associations from surveys of rocky intertidal communities in the Northeast Pacific Ocean. We compared those inferred associations with a new data set of experimentally determined net and direct species interactions. Although association methods generated networks with aggregate structure similar to previously published interaction networks, each method detected a different set of species associations from the same data set. Moreover, although association methods generally performed better than a random model, associations rarely matched empirical net or direct species interactions, with high rates of false positives and true positives, and many false negatives. Our findings cast doubt on studies that equate species co‐occurrences to species interactions and highlight a persistent, unanswered question: how do we interpret spatial patterns in communities? We suggest future research directions to unify the observational and experimental study of species interactions, and discuss the need for community standards and best practices in association analysis.
Risk of stroke and bleeding in patients with heart failure and chronic kidney disease: a nationwide cohort study
Authors: Melgaard Line , Overvad Thure Filskov , Skjøth Flemming , Christensen Jeppe Hagstrup , Larsen Torben Bjerregaard , Lip Gregory Y.H.
Published: January 2018

Aims

The aim of this study was to assess the prognostic value of chronic kidney disease (CKD) in relation to ischaemic stroke, intracranial haemorrhage, major bleeding, and all‐cause death in heart failure patients without atrial fibrillation.

Methods and results

In this observational cohort study, heart failure patients without atrial fibrillation were identified using Danish nationwide registries. Risk of stroke, major haemorrhage, and death were calculated after 1 and 5 years to compare patients with and without CKD, ±dialysis [dialysis: CKD with renal replacement therapy (CKD‐RRT); no dialysis: CKD‐no RRT]. A total of 43 199 heart failure patients were included, among which 0.8% had CKD‐RRT and 5.9% had CKD‐no RRT. When compared with heart failure patients without CKD, both CKD‐RRT and CKD‐no RRT were associated with a higher 5 year rate of major bleeding (CKD‐RRT: adjusted hazard ratio (aHR): 2.91, 95% confidence interval (CI): 2.29 to 3.70; CKD‐no RRT: aHR: 1.28, 95% CI: 1.13 to 1.45) and all‐cause death (CKD‐RRT: aHR: 2.40, 95% CI: 2.07 to 2.77; CKD‐no RRT: aHR: 1.63, 95% CI: 1.55 to 1.73). For the endpoints of ischaemic stroke and intracranial bleeding, only CKD‐no RRT was associated with significantly higher 5 year rates (ischaemic stroke: aHR: 1.31, 95% CI: 1.13 to 1.52; intracranial haemorrhage: aHR: 1.66, 95% CI: 1.04 to 2.65).

Conclusions

Compared with patients without CKD, among incident heart failure patients without atrial fibrillation, CKD both with and without dialysis was associated with a higher rate of major bleeding and all‐cause death. Only CKD‐no RRT was associated with a higher rate of ischaemic stroke and intracranial bleeding.
Coordination Chemistry of the Redox Non‐Innocent Ligand Bis(2‐amino‐3,5‐di‐tert‐butylphenyl)amine with Group 10 Metal Ions (Ni, Pd, Pt)
Authors: Leconte Nicolas , Moutet Jules , Constantin Thibaut , Molton Florian , Philouze Christian , Thomas Fabrice
Published: January 2018

The pincer ligand H3L3N, bis(2‐amino‐3,5‐di‐tert‐butylphenyl)amine}, was chelated to NiII, PdII, and PtII. Square‐planar complexes of stoichiometry 2:1 (ligand/metal) formed, wherein the ligand coordinates in a bidentate fashion. By X‐ray diffraction we established that each ligand molecule coordinates in its diiminosemiquinone radical form in the neutral NiII, PdII, and PtII complexes (1, 2, and 3, respectively). The resulting systems are singlet diradical species, with a predicted J value in the range –1062 to –1764 cm–1. These diradicals display an intense LLCT transition involving the diiminosemiquinone moieties: 860, 852, and 760 nm for 1, 2, and 3, respectively. Complex 1, 2, and 3 exhibit reversible oxidation waves in their CV curves. Cations 1+, 2+, and 3+ are (S = 1/2) systems with g values close to 2. The increase in the intensity of the resonance in the order 1+ < 2+, 3+ is consistent with the easy comproportionation of 1+. X‐ray diffraction analysis discloses that 3+ is a mixed‐valent radical mononuclear complex. An intense IVCT is observed at low energy (1536, 1656, and 1256 nm for 1+, 2+, and 3+, respectively), confirming that this classification applies to all the cations. Dications 12+, 22+, and 32+ are closed‐shell bis(diiminobenzoquinone) species. The crystal structure of 32+ shows that this complex exhibits the shortest mean C–N bond lengths within the series.
Improving Storage Stability of Pistachio Oil Packaged in Different Containers by Using Rosemary (Rosmarinus officinalis L.) and Peppermint (Mentha piperita) Essential Oils
Authors: Esmaeili Moein , Goli Sayed A. H. , Shirvani Atefe , Shakerardakani Ahmad
Published: January 2018

In this study, the antioxidant capacity of rosemary (REO) and peppermint (PEO) essential oils along with butylated hydroxytoluene (BHT) is investigated on oxidative stability of pistachio oil packaged in glass and polyethylene terephthalate (PET). The essential oils (EOs) and their mixture are added at 1500 and 3000 ppm concentrations into the oil stored for 80 days at 60 °C under darkness. In order to evaluate the efficacy of antioxidants, peroxide value (PV), thiobarbituric acid, total phenolic compounds, oxidative stability index (OSI), conjugated dienes and trienes, free fatty acids (FFAs), and iodine value is measured at intervals of 20 days. The results show that natural antioxidants can reduce PV and FFA levels about five‐ and threefolds compared to control, respectively. The OSI in raw pistachio oil (16 h) reduces to 5 h, while in treated sample by REO the reduction is only to 13 h after storage. Generally, the results reveal that in all measured parameters, following order can be observed for antioxidant activity: 3000 ppm REO>3000 ppm PEO>100 ppm BHT >1500 ppm REO >1500 ppm mixed >1500 ppm PEO > control. Moreover, the findings show that glass container is better than PET to retard oxidation process.

Practical Application: Pistachio oil is known as a functional and commercial oil that is susceptible to oxidation due to its high level of unsaturated fatty acids. In this work, rosemary and mint essential oils as natural antioxidant are applied for improving oxidation stability of pistachio oil.

Antioxidant capacity of rosemary (REO) and peppermint (PEO) essential oils is investigated on oxidative stability of pistachio oil packaged in glass and polyethylene terephthalate (PET). The essential oils are added at 1500 and 3000 ppm concentrations into the oil stored for 80 days at 60 ºC under darkness. The results reveal that in all measured parameters, following order can be observed for antioxidant activity: 3000 ppm REO >3000 ppm PEO >100 ppm BHT >1500 ppm REO >1500 ppm mixed >1500 ppm PEO > control. The findings show that glass container is better than PET to retard oxidation process.
Iron‐Catalyzed Sulfur‐Promoted Decyanative Redox Condensation of o‐Nitrophenols and Arylacetonitriles: An Unprecedented Route to 2‐Arylbenzoxazoles
Authors: Nguyen Thanh Binh , Lung Jerome Cheung
Published: January 2018

Elemental sulfur in the presence of a catalytic amount of FeCl2·4H2O was found to be highly efficient for the promotion of decyanative redox condensation reactions of o‐nitrophenols with arylacetonitriles, to give a wide range of 2‐arylbenzoxazoles. The utility of elemental sulfur was highlighted by its role as cyanide scavenger and external reducing agent.
One‐Pot Sequential Photoredox Chemistry and Asymmetric Transfer Hydrogenation with a Single Catalyst
Authors: Zhang Xiao , Qin Jie , Huang Xiaoqiang , Meggers Eric
Published: January 2018

A sequential process is reported, in which different photoredox reactions are placed in sequence with asymmetric transfer hydrogenations of aryl ketones to provide a diverse set of chiral alcohols with enantioselectivities of up to 99 % ee. The method relies on a single chiral‐at‐metal catalyst which is added at the beginning of the two step sequence and only a final purification of the reaction product is required.
Capacitive coupling synchronizes autonomous microfluidic oscillators
Authors: Lesher‐Pérez Sasha Cai , Zhang Chao , Takayama Shuichi
Published: January 2018

Even identically designed autonomous microfluidic oscillators have device‐to‐device oscillation variability that arises due to inconsistencies in fabrication, materials, and operation conditions. This work demonstrates, experimentally and theoretically, that with appropriate capacitive coupling these microfluidic oscillators can be synchronized. The size and characteristics of the capacitive coupling needed and the range of input flow rate differences that can be synchronized are also characterized. In addition to device‐to‐device variability, there is also within‐device oscillation noise that arises. An additional advantage of coupling multiple fluidic oscillators together is that the oscillation noise decreases. The ability to synchronize multiple autonomous oscillators is also a first step towards enhancing their usefulness as tools for biochemical research applications where multiplicate experiments with identical temporal‐stimulation conditions are required.
Response of braiding channel morphodynamics to peak discharge changes in the Upper Yellow River
Authors: Schuurman Filip , Ta Wanquan , Post Sander , Sokolewicz Marius , Busnelli Marcela , Kleinhans Maarten
Published: January 2018

The braiding intensity and dynamics in large braiding rivers are well known to depend on peak discharges, but the response in braiding and channel–floodplain transformations to changes in discharge regime are poorly known. This modelling study addresses the morphodynamic effects of increasing annual peak discharges in braiding rivers. The study site is a braiding reach of the Upper Yellow River. We estimated the effects on the larger‐scale channel pattern, and on the smaller‐scale bars, channel branches and floodplains. Furthermore, we determined the sensitivity of the channel pattern to model input parameters. The results showed that the dominant effect of a higher peak discharge is the development of chute channels on the floodplains, formed by connecting head‐cut channels and avulsive channels. Widening of the main channel by bank erosion was found to be less dominant. In addition, sedimentation on the bars and floodplains increased with increasing peak discharge. The model results also showed that the modelled channel pattern is especially sensitive to parametrization of the bed slope effect, whereas the effect of median grain size was found to be relatively small. Copyright © 2018 John Wiley & Sons, Ltd.
Outcomes utilizing intensity‐modulated radiotherapy in oropharyngeal cancers: Tonsils versus base of tongue
Authors: Kanakamedala Madhava R. , Giri Shankar P. G. , Hamilton Robert D. , Bhanat Eldrin , Vijayakumar Srinivasan
Published: January 2018

Background

The purpose of this study was to present the outcomes of oropharyngeal cancers treated with intensity‐modulated radiotherapy (IMRT) especially the differences between tonsillar and base of tongue (BOT) primaries.

Methods

Retrospective analysis of 124 patients with biopsy proven squamous cell carcinomas of the oropharynx, treated with IMRT.

Results

Human papillomavirus (HPV) association correlated with improvement in survivals in both tonsillar and BOT primaries. At the 2‐year median follow‐up, the cumulative incidences of locoregional recurrences were 8% in both the tonsil and BOT groups (P = .76) but the distant metastases were 8% in the tonsil group versus 26% in the BOT group (P = .009). Thirty percent of tonsil primaries has ≥N2c neck disease as compared to 54% of BOT. Incidence of distant metastases increases with advanced nodal classification, especially >N2c.

Conclusion

Even though the locoregional controls are excellent with IMRT and chemotherapy, these patients continue to fail distantly, particularly significant for the BOT group and for nodal stage >N2c.
Modified combination of platelet count and neutrophil “to” lymphocyte ratio as a prognostic factor in patients with advanced head and neck cancer
Authors: Nakayama Masahiro , Gosho Masahiko , Hirose Yuki , Nishimura Bungo , Tanaka Shuho , Tabuchi Keiji , Okubo Hideki , Wada Tetsuro , Hara Akira
Published: January 2018

Background

We evaluated the prognostic potential of the combination of platelet count and neutrophil to lymphocyte ratio (COP‐NLR) in patients with advanced head and neck cancer.

Methods

We proposed a modified COP‐NLR scoring system defined as follows: score 0 (platelet count level <300 × 109/L and NLR <3); score 1 (platelet count level ≥300 × 109/L and NLR <3); and score 2 (NLR ≥3). We assessed whether the modified scoring system had better performance as an indicator of prognosis than the existing COP‐NLR scoring system (original and 4‐group scores).

Results

A total of 248 patients were enrolled. The Akaike Information Criterion value with the modified COP‐NLR score was the smallest among the 3 models. The 3‐year survival rates according to the modified COP‐NLR scores of 0, 1, and 2 were 80.6%, 59.9%, and 23.8%, respectively.

Conclusion

The modified COP‐NLR score is a useful prognostic marker in patients with advanced head and neck cancer.
Prognostic factors for soft tissue sarcoma patients with lung metastases only who are receiving first‐line chemotherapy: An exploratory, retrospective analysis of the European Organization for Research and Treatment of Cancer‐Soft Tissue and Bone Sarcoma Group (EORTC‐STBSG)
Authors: Lindner Lars H. , Litière Saskia , Sleijfer Stefan , Benson Charlotte , Italiano Antoine , Kasper Bernd , Messiou Christina , Gelderblom Hans , Wardelmann Eva , Le Cesne Axel , Blay Jean‐Yves , Marreaud Sandrine , Hindi Nadia , Desar Ingrid M.E. , Gronchi Alessandro , van der Graaf Winette T.A.
Published: January 2018

The prognosis of adult soft tissue sarcoma (STS) patients with metastases is generally poor. As little is known about the impact of the involvement of different metastatic sites and the extent of pulmonary lesions on the outcome for patients receiving first‐line chemotherapy, we aimed to establish prognostic factors for STS patients with lung metastases only. A retrospective, exploratory analysis was performed on 2,913 metastatic STS patients who received first‐line chemotherapy. Detailed information from 580 patients who had lung metastases only, was used for prognostic factor analysis. Patients with lung metastases only were more often asymptomatic and had undergone complete primary tumor resection more frequently compared to patients with additional metastases outside the lung or without lung metastases. For extremity STS, the incidence of lung metastases only was much higher compared to non‐extremity STS. Lung involvement only was an independent favorable prognostic factor for overall survival (OS) with regard to metastatic site. Within this subgroup, in a multivariate model, other factors associated with improved OS included: good performance status (PS), no progression at primary site, low histological grade, younger age, long interval between initial diagnosis and trial registration, and smaller diameter of the largest lung lesion. This unique analysis on prognostic factors in STS patients with lung metastases confirms well‐known patient factors (such as age and PS), and tumor characteristics (including tumor grade, interval between primary diagnosis, and metastases), but also identifies diameter of the largest lung lesion as a new prognostic factor. Knowledge about these factors may support decision‐making within multidisciplinary tumor boards.
GENETICS OF SORDARIA FIMICOLA. III. CROSS‐COMPATIBILITY AMONG SELF‐FERTILE AND SELF‐STERILE CULTURES
Authors: Carr A. J. H. , Olive Lindsay S.
Published: January 2018

Carr, A. J. H. (Univ. Coll. Wales, Aberystwyth), and Lindsay S. Olive. Genetics of Sordaria fimicola. III. Cross compatibility among self‐fertile and self‐sterile cultures. Amer. Jour. Bot. 46(2) : 81‐91. Illis. 1959.—Cross‐compatibility in Sordaria fimicola is shown to be dependent upon a number of factors controlling the sexual process, from hyphal anastomosis and nuclear migration on through to perithecial formation and nuclear compatibility. Fertile cultures which were incompatible through inability to anastomose were induced to cross by the use of a third culture which would anastomose with both. Certain spontaneous or irradiation‐produced sterility mutants were found to be compatible if the sterility genes were at different loci, through complementation by the wild‐type alleles. In some pairings, cross‐karyogamy was preferential, and in one case, only hybrid perithecia were produced. Fully fertile recombinants segregated from these crosses in frequencies which indicated that the sterility loci were unlinked. Certain sterility genes were found to influence hyphal anastomosis, nuclear migration, and the development of fertile sector heterokaryons from the zone of anastomosis. Mutant factors at two loci in a U.V. mutant causing self‐sterility were found also to be responsible for lethality in ascospore germination. Factors in one sterility mutant controlled the production of a sterility‐inducing substance which diffused into the medium. In some crosses, complementation of two sterile cultures towards fertility is shown to require a balanced nuclear ratio. Factors are described which increase the inhibitory effect of one sterility gene, while another factor was found to suppress its effect and thereby make the culture self‐fertile. It is concluded that, since there is recombination between the sterility loci, these results do not represent the derivation of balanced heterothallism from a normally homothallic system, although it may lead by evolutionary progression to such a life cycle. The possible physiologic action of the sterility genes is discussed.
GROWTH OF THE EMBRYO OF GINKGO BILOBA UNDER EXPERIMENTAL CONDITIONS. III. GROWTH RATES OF ROOT AND SHOOT UPON MEDIA ABSORBED THROUGH THE COTYLEDONS
Authors: Ball Ernest
Published: January 2018

Ball, Ernest. (North Carolina State Coll., Raleigh.) Growth of the embryo of Ginkgo biloba under experimental conditions. III. Growth rates of root and shoot upon media absorbed through the cotyledons. Amer. Jour. Bot. 46(2) : 130‐139. Illus. 1959.—Mature embryos of Ginkgo biloba were grown by inserting the cotyledons into agar medium containing one of the naturally‐occurring sugars of the seed. These sugars were utilized at 1, 2, 4, 8 or 16% (w/v). Root growth was best on the sugar‐mineral‐water media and occurred at its maximum in media containing 4% sugar (ca. 0.25 M). The sugars may be listed as follows in order of decreasing effectiveness in root growth: glucose, sucrose, levulose, raffinose, galactose. Since very different growth rates of roots occurred on media of the same osmotic values when the latter were determined by the various sugars, it is suggested that the root utilized the entire sugar molecule as a unit whether it was mono‐, di‐, or trisaccharide. Such media were not effective in supporting shoot growth. Outstanding growth of shoots was obtained when either glutamine or coconut milk was placed in the culture medium. It is concluded that root growth can occur at a substantial rate by utilizing sugar and manufacturing organic nitrogen from nitrates. Shoot growth, in contrast, appears to require sources of organic nitrogen such as may be furnished by glutamine or coconut milk. These phenomena are thought to constitute fundamental differences between the metabolism of root and shoot of this embryo. Mannitol caused severe inhibition of growth of both root and shoot. It is probably toxic to this embryo. Indoleacetic acid caused severe inhibitions of growth of both root and shoot at all except the lowest concentrations utilized.
INFLUENCE OF N‐(TRICHLOROMETHYLTHIO)‐4‐CYCLOHEXENE‐1,2‐DICARBOXIMIDE (CAPTAN) ON HIGHER PLANTS. II. EFFECT ON SPECIFIC ENZYME SYSTEMS
Authors: Dugger W. M. , Humphreys T. E. , Calhoun Barbara
Published: January 2018

Dugger, W. M., Jr., T. E. Humphreys, and Barbara Calhoun. (Florida Agric. Expt. Sta., Gainesville.) Influence of N‐(trichloromethylthio) ‐4‐cyclohexene‐1,2‐dicarboximide (captan) on higher plants. II. Effect on specific enzyme systems. Amer. Jour. Bot. 46(3) : 151‐156. Illus. 1959.—The effect of N‐(trichloromethylthio)‐4‐cyclohexene‐1,2‐dicarbomixide (captan) and 2 analogs on specific enzyme systems associated with plant metabolism has been studied. The fungicide inhibits yeast hexokinase, but not hexokinase from wheat germ or pea seedlings. Decarboxylation of pyruvate and α‐ketoglutarate by lupine mitochondria was inhibited by captan and the phthalimide and hexahydrophthalimide analogs. This inhibition was reversible, at low levels of the fungicides, by adding cocarboxylase. The oxidation of ribose‐5‐phosphate by pea extract was also inhibited by captan and the hexadehydro analog, but cocarboxylase did not reduce the inhibition. TPN reduction was not affected.
GENETIC HISTORY AND GENERAL COMPARISONS OF TWO ALBINO MUTATIONS OF HELIANTHUS ANNUUS
Authors: Wallace Raymond H. , Habermann Helen M.
Published: January 2018

Wallace, Raymond H. (U. Connecticut, Storrs.), and Helen M. Habermann. Genetic history and general comparisons of two albino mutations of Helianthus annuus. Amer. Jour. Bot. 46(3) : 157‐162. Illus. 1959.—The genetic history of the progeny of a single ultrasonically‐treated seedling of Helianthus annuus L. has been summarized for the 6 generations for which quantitative data are available. A yellow mutation was found in the F2 generation and later in the F5, a second, white mutation occurred. Both mutants have been grown to maturity by grafting them onto normal green host plants and they have set viable seeds. Both pigment‐deficient conditions are inherited as single recessive factors. These albino strains form chlorophyll during their seedling stages if they are grown at low light intensities. Chlorophyll is destroyed, however, under bright illumination and, once bleached, the capacity for chlorophyll formation appears to be lost. The yellow mutant contains xanthophyll but no traces of carotene have been found. In the white mutant, neither carotene nor xanthophyll have been detected. Flower color in the yellow mutant is normal while the flowers of the white mutant have no apparent pigmentation. The growth pattern of grafted yellow mutants is normal, save for a stiffer and woodier condition and a greater resistance to wilting. These characteristics have also been observed in grafted white mutants. In addition, there is a pronounced reduction in leaf size in the white mutant.
INTERSPECIFIC INCOMPATIBILITY IN PINUS
Authors: McWilliam J. R.
Published: January 2018

McWilliam, J. R. (C. S. I. R. O., Canberra, Australia). Interspecific incompatability in Pinus. Amer. Jour. Bot. 46(6): 425–433. Illus. 1959.—The problem of interspecific incompatibility in several intra‐ and intersectional crosses in the genus Pinus was investigated using both an anatomical and biochemical approach. To provide a background for this work, the development of ovules after intraspecific pollination and of unpollinated ovules was studied. The development of the gametophytes and fertilization after intraspecific pollination in Austrian pine was regular and showed no major deviation from previous descriptions. Unpollinated ovules of Austrian pine broke down approximately 1 mo. after the strobilus became receptive. The break‐down appears to result from the lack of some growth factor in the ovule, which in pollinated ovules is probably initiated by the growth of the pollen tube in the nucellus. Parthenocarpy was not observed, nor could it be induced in unpollinated ovules, and it is considered to be a rare phenomenon in the species. The causes of incompatibility in the crosses studied (slash pine × Austrian pine; red pine × pitch pine; Austrian pine × pitch pine; red pine × Austrian pine; Austrian pine × red pine) appear to be related to the inability of the pollen tubes to function normally in the nucellar tissue of a foreign species. Factors that interfere with this normal development indirectly cause the breakdown of the developing gametophyte, and bring about the ultimate collapse of the ovule. In many respects this pattern of development resembles the situation in unpollinated ovules, and again the lack of a specific growth factor appears to be involved. The initial cause of incompatibility following the cross Austrian pine X red pine may be related to a chemical difference between the ovules of these species. Differences found in the concentration of amino acids, particularly arginine, result in a different chemical environment within the ovule. This may interfere with the normal metabolism of the pollen, affecting either its capacity to germinate or its ability to supply the necessary continued stimulus for the development of the gametophyte. Differences in the pattern and timing of the incompatibility reaction following interspecific pollination may reflect the extent of the genetic diversity between the species. In many crosses between species, the incompatibility reaction does not seem to be complete, as evidenced by the vigorous initial pollen tube growth in occasional ovules.
THE ASSOCIATION OF A SINGLE B‐CHROMOSOME WITH MALE STERILITY IN PLANTAGO CORONOPUS
Authors: Paliwal Ripusudan L. , Hyde Beal B.
Published: January 2018

Paliwal, Ripsudan L. (B. R. College, Agra, India.), and Beal B. Hyde. The association of a single B‐chromosome with male sterility in Plantago coronopus. Amer. Jour. Bot. 46(6): 460–466. Illus. 1959.—Two species of Plantago showing male sterility have been studied cytogenetically. In P. ovata (n=4) the sterility appears to be cytoplasmic. In P. coronopus (n=5) all male‐sterile plants contain a single extra chromosome which is largely heterochromatic, shorter, and not homologous with any of the other chromosomes. No male‐fertile plants contain this B‐chromosome. Meiosis is regular in the male‐sterile lines. The accessory chromosome usually does not divide and moves to one pole at the first division of meiosis and divides regularly in the second division. Degeneration of all microspores occurs before pollen mitosis. Male‐sterile plants are apomictic, but whether or not male‐fertile plants are also apomictic has not yet been determined.
CHITIN AND CELLULOSE IN THE CELL WALLS OF RHIZIDIOMYCES SP
Authors: Fuller Melvin S. , Barshad Isaac
Published: January 2018

Fuller, Melvin S. (Brown U. Providence, R. I.), and Isaac Barshad. Chitin and cellulose in the cell walls of Rhizidiomyces sp. Amer. Jour. Bot. 47(2): 105‐109. Illus. 1960.–Chemically isolated cell wall preparations of the aquatic Phycomycete, Rhizidiomyces sp., were analyzed by means of X‐rays. The resulting diffraction patterns had maxima corresponding with known values for chitin and mercerized cellulose. The findings in this study are discussed with respect to Von Wettstein's hypothesis that the aquatic Phycomycetes can be separated into groups on the basis of whether their cell walls contain chitin or cellulose.
DEVELOPMENT OF THE SEED OF SOLANUM PHUREJA
Authors: Dnyansagar Vishnu R. , Cooper Delmer C.
Published: January 2018

Dnyansagab, Vishnu R., and Delmer C. Cooper. (U. Wisconsin, Madison.) Development of the seed of Solanum phureja. Amer. Jour. Bot. 47(3) : 176—186. Illus. 1960.—Ontogeny of the seed of Solanum phureja Juz. et Buk. is described. The megagametophyte, during the course of its development, ruptures the nucellus and at maturity lies in direct contact with the inner layer (endothelium) of the single massive integument. The mature megagametophyte, a 7‐celled structure, consists of a 3‐celled egg apparatus, an endosperm mother cell with fused polar nuclei and 3 persistent antipodals. Both 2‐ and 3‐celled mature pollen grains are formed within anthers of the same flower; hence this character cannot be considered of any taxonomic value. Double fertilization occurs between 24 and 72 hr. after pollination. A cellular endosperm is formed, the peripheral layer acting as an absorbing tissue during the early ontogeny of the seed. Later this layer becomes organized as an aleurone layer and thereafter the source of nutrients is via the basal portion of the endosperm immediately adjacent to the apical end of the vascular tissue of the developing seed. Embryo development follows the Nicotiana variation of the Solanad type. The mature testa is composed of an outer layer of thick‐walled epidermal cells, an inner layer of thin‐walled cells and an intervening mass of disorganized tissue. In those instances where the ovule or young seed aborts, the endothelial cells of the integument become hyperactive and proliferate to such an extent that the space formerly occupied by the gametophyte or the developing endosperm and embryo becomes completely filled with endothelial tissue.
THALASSIOMYCETES II. NEW GENERA AND SPECIES OF DEUTEROMYCETES
Authors: Meyers Samuel P. , Moore Royall T.
Published: January 2018

Meyers, Samuel P. (U. Miami, Coral Gables, Fla.) and Royall T. Moore. Thalassiomycetes II. New genera and species of Deuteromycetes. Amer. Jour. Bot. 47(5) : 345‐349. Illus. 1960.–On the basis of taxonomic studies, 3 new monotypic thalassic genera are erected. These are: Cirrenalia, type C. macrocephala (=Helicoma macrocephala Kohlmeyer) ; Cremasteria, type C. cymatilis; Culcitalna, type C. achraspora. Also described is a new species of Humicola, H. alopallonella, which constitutes the first report of this genus from the marine environment.
ENDOGENOUS RHYTHM IN OPENING AND ODOR OF FLOWERS OF CESTRUM NOCTURNUM
Authors: Overland Lillian
Published: January 2018

Overland, Lillian. (Missouri Botanical Garden, St. Louis.) Endogenous rhythm in opening and odor of flowers of Cestrum nocturnum. Amer. Jour. Bot. 47(5): 378—382. Illus. 1960.–The opening and closing of flowers of Cestrum nocturnum have been found to occur in a cyclic manner both in constant light and constant darkness at constant temperature. The strong odor, which in nature occurs at night and was previously believed to be a direct result of darkness, has been shown to exist as an endogenous rhythm, occurring under constant conditions of temperature and light, as well as in darkness. Although in nature the odor cycle is so synchronized by the environment as to have a period of roughly 24 hr., in constant conditions temperature affects the cycle by lengthening it at low temperature and reducing it at high temperature. The cycle may be disrupted by shifting between extreme temperatures, but it is not destroyed. The controlling mechanism for odor production seems to be located in the tips of the corolla and the cycle exists independently in the excised tips.
SOME NEW AND INTERESTING SPECIES OF TREBOUXIA, A GENUS OF LICHENIZED ALGAE
Authors: Ahmadjian Vernon
Published: January 2018

Ahmadjian, Vernon. (Clark U., Worcester, Mass.) Some new and interesting species of Trebouxia, a genus of lichenized algae. Amer. Jour. Bot. 47 (8): 677–683. Illus. 1960.—Four species of the phycobiont Trebouxia, 3 of which are new, have been described in this paper. On the basis of this study, the algal genus has been divided into 2 main groups depending on the position that the chromatophore assumes during its bipartitions and on the shape of the cells. Growth rates have been calculated and growth curves drawn for the various species. In some cases, a physiological difference was shown between morphologically identical forms. In several instances, the same algal symbiont was isolated from widely separated lichen species, a fact which is contrary to earlier claims of the high specificity of the lichen fungus to its algal component.
THE EFFECTS OF MECHANICAL STIMULATION AND ETIOLATION ON THE COLLENCHYMA OF DATURA STRAMONIUM
Authors: Walker Waldo S.
Published: January 2018

Walker, Waldo S. (Grinnell College, Grinnell, Iowa.) The effects of mechanical stimulation and etiolation on the collenchyma of Datura stramonium. Amer. Jour. Bot. 47(9) : 717–724. Illus. 1960.–In an effort to determine the effect of mechanical stimulation on collenchyma tissue, plants of Datura stramonium L. were placed on a mechanical agitator and subjected to intensive shaking for 9 hr. per day for 40 days. Measurements indicated that such stimulation greatly increased the amount of wall thickening per cell, as observed in transverse section. Measurements also indicated that such stimulation may inhibit collenchyma cell elongation. A second group of Datura stramonium plants was placed in total darkness to determine the effect of such treatment on the quantity of wall thickening in the collenchyma tissue. Measurements indicated that when plants were placed in the dark for extended periods a great reduction of wall thickening resulted. It is suggested that reduction of wall material was due to its utilization as substrate for respiratory processes which occur in the plant under such extreme conditions. The composition and structure of the collenchyma cell walls are discussed.
INVESTIGATIONS OF NORTH AMERICAN CYCADEOIDS: TRUNKS FROM WYOMING
Authors: Delevoryas Theodore
Published: January 2018

Delevoryas, Theodore. (University of Illinois, Urbana.) Investigations of North American cycadeoids: trunks from Wyoming. Amer. Jour. Bot. 47(9): 778–786. Illus. 1960.—A study was undertaken of the cycadeoid trunks from Wyoming to more fully understand the morphology and evolutionary significance of these trunks and to determine the validity of the genus Cycadella. The stem named Cycadeoidea (or Cycadella) utopiensis is not the same morphologically as those from Carbon County, Wyoming, and because of its unknown source, it is not a reliable specimen for the study of cycadeoids from the Morrison formation. The Morrison, Carbon County specimens included in Ward's genus Cycadella were shown to have trunk structure, leaf bases, and cones like those in Cycadeoidea. The cone vascular bundle is derived from a fusion of 4 leaf traces. From the fused bundle complex, 4 leaf traces are separated farther out in the cortex, and 1 of these supplies the subtending leaf. In spite of the relatively complex pattern of cone trace formation, there does not seem to be any significant means of distinguishing specimens called Cycadella from the more common Cycadeoidea. Furthermore, it is evident that the genus Cycadeoidea represents a fairly homogeneous group with a wide geographic and geologic range. Pattern of formation of cone traces is interpreted as possible further evidence for regarding cycadeoid cones as portions of foliar systems.