bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat‐Sink‐Free Flexible Organic Thermoelectric Generator Vertically Operating with Chevron Structure
Authors: Kim Daegun , Ju Duckhyun , Cho Kilwon
Published: January 2018

Organic thermoelectric (TE) material receives increasing attention as a promising candidate for flexible TE generators, which is required for wearable applications such as self‐powered electronics, sustainable mobile batteries, and medical sensors. Recent advances in TE figure‐of‐merit of organic TE material reach that of bulk inorganic TE material. However, organic TE material is not fully functionalized to the TE generator, which shows low power output, operates in a lateral heat flow, and requires an additional heat sink. A flexible organic TE generator is presented herein by introducing an optimized solution process, chevron device structure, and a foam medium. Optimized poly(3,4‐ethylenedixoythiophene):polystyrene sulfonate (PEDOT:PSS) film involves a distinctive film morphology, achieving a high power factor (642 µW m−1 K−2) and a low sheet resistance (<10 Ω sq−1). A chevron‐structured TE generator, integrating 24 PEDOT:PSS patterns, is highly flexible and yields a remarkable TE output (≈1 µW at ΔT = 17.5 K) in a vertical heat flow. In addition, internal thermal transport through the device is systematically controlled by the inserted medium, which enables the heat‐sink‐free operation of the TE generator retaining 70% of its maximum voltage output in the absence of an additional heat sink.
Designing Redox‐Stable Cobalt–Polypyridyl Complexes for Redox Flow Batteries: Spin‐Crossover Delocalizes Excess Charge
Authors: Yang Chunzhen , Nikiforidis Georgios , Park Ji Young , Choi Jonghoon , Luo Yong , Zhang Liang , Wang Shi‐Cheng , Chan Yi‐Tsu , Lim Jihun , Hou Zhaomin , Baik Mu‐Hyun , Lee Yunho , Byon Hye Ryung
Published: January 2018

Redox‐active organometallic molecules offer a promising avenue for increasing the energy density and cycling stability of redox flow batteries. The molecular properties change dramatically as the ligands are functionalized and these variations allow for improving the solubility and controlling the redox potentials to optimize their performance when used as electrolytes. Unfortunately, it has been difficult to predict and design the stability of redox‐active molecules to enhance cyclability in a rational manner, in part because the relationship between electronic structure and redox behavior has been neither fully understood nor systematically explored. In this work, rational strategies for exploiting two common principles in organometallic chemistry for enhancing the robustness of pseudo‐octahedral cobalt–polypyridyl complexes are developed. Namely, the spin‐crossover between low and high‐spin states and the chelation effect emerging from replacing three bidentate ligands with two tridentate analogues. Quantum chemical models are used to conceptualize the approach and make predictions that are tested against experiments by preparing prototype Co‐complexes and profiling them as catholytes and anolytes. In good agreement with the conceptual predictions, very stable cycling performance over 600 cycles is found.
Improving Performance Measures With Perioperative Analytics
Authors: Dewes Andi
Published: January 2018

Perioperative nurses and leadership teams across the country strive to improve outcomes, increase operational efficiency, and achieve performance improvement on key measures in the perioperative department. In today's changing health care environment, which involves increasing pressure to do more with less, it is essential for perioperative leaders to understand analytics and how to use analytics to identify, plan, and implement improvement initiatives that will provide the greatest value. This article examines key performance indicators in the OR, barriers to change, and the strategies and processes that perioperative leaders can use to achieve efficiency and performance improvement goals. It also provides an example of a tactical approach to one of the OR's greatest challenges: measuring and improving block utilization.
Building a developmental toxicity ontology
Authors: Baker Nancy , Boobis Alan , Burgoon Lyle , Carney Edward , Currie Richard , Fritsche Ellen , Knudsen Thomas , Laffont Madeleine , Piersma Aldert H. , Poole Alan , Schneider Steffen , Daston George
Published: January 2018

Background

As more information is generated about modes of action for developmental toxicity and more data are generated using high‐throughput and high‐content technologies, it is becoming necessary to organize that information. This report discussed the need for a systematic representation of knowledge about developmental toxicity (i.e., an ontology) and proposes a method to build one based on knowledge of developmental biology and mode of action/ adverse outcome pathways in developmental toxicity.

Methods

This report is the result of a consensus working group developing a plan to create an ontology for developmental toxicity that spans multiple levels of biological organization.

Results

This report provide a description of some of the challenges in building a developmental toxicity ontology and outlines a proposed methodology to meet those challenges. As the ontology is built on currently available web‐based resources, a review of these resources is provided. Case studies on one of the most well‐understood morphogens and developmental toxicants, retinoic acid, are presented as examples of how such an ontology might be developed.

Discussion

This report outlines an approach to construct a developmental toxicity ontology. Such an ontology will facilitate computer‐based prediction of substances likely to induce human developmental toxicity.
Circulating molecules that control brown/beige adipocyte differentiation and thermogenic capacity
Authors: Ludwig Raissa G. , Rocha Andréa L. , Mori Marcelo A.
Published: January 2018

Obesity may be counteracted by increased energy expenditure. Circulating molecules act in the adipose tissue to influence brown and beige adipocyte function, differentiation, and thermogenic capacity, which in turn affects substrate utilization and impacts energy balance at the organismal level. These molecules have been envisioned as biomarkers and potential candidates for pharmacological interventions to treat obesity. Here we summarize studies that demonstrate the roles of endogenous circulating molecules of a wide variety in regulating the thermogenic potential of brown and beige fat cells. This review describes the state‐of‐the‐art in the field and helps researchers to prioritize their targets in future studies.
Indomethacin induced ductus arteriosus closure in midgestation fetus
Authors: Beaute Jeanette I. , Friedman Kevin G.
Published: January 2018

Key Clinical Message

This article reports a rare but potentially serious complication of ductus arteriosus closure resulting from second‐trimester indomethacin exposure. Serial echocardiograms are indicated to monitor for development of right heart dysfunction and to ensure delivery prior to the onset of right heart failure and hydrops fetalis.
The role of multidetector CT angiography and 3D postprocessing imaging in the diagnosis and investigation of bronchopulmonary sequestration
Authors: Spartalis Eleftherios , Spartalis Michael , Moris Demetrios , Athanasiou Antonios , Troupis Theodore , Tomos Periklis
Published: January 2018

Key Clinical Message

Congenital bronchopulmonary malformations are usually asymptomatic. Precise multimodality imaging plays an essential role in the identification of rare cardiothoracic entities, offering excellent imaging quality and the decisive diagnosis.
Severe pancytopenia and splenomegaly associated with felty's syndrome, both fully responsive solely to corticosteroids
Authors: Liatsos George D. , Tsironi Ioanna , Vassilopoulos Dimitrios , Dourakis Spyridon
Published: January 2018

Key Clinical Message

In severe cases of pancytopenia with subsequent infections due to long‐term untreated Felty's syndrome, the initiation of immunosuppressive treatment with sole prednisone (1 mg/kg iv) should be considered, despite that, the low neutrocytes count would make one physician hesitant. A full resolution of whole blood count within 3 weeks and a 30% reduction in spleens sized was noted.
Direct Factor X sequestration by systemic amyloid light‐chain amyloidosis
Authors: Tashiro Haruko , Shirasaki Ryosuke , Watanabe Masato , Kawasugi Kazuo , Takahashi Yoshihisa , Shirafuji Naoki
Published: January 2018

Key Clinical Message

We present a lymphoplasmacytic lymphoma patient with Factor X (FX) deficiency. Despite the absence of FX inhibitor, the administration of fresh frozen plasma and anti‐inhibitor coagulant complex did not increase the FX level. The autopsy showed that massive amyloid depositions to multiple organs and FX existed in union with amyloidosis.
Visible‐Light‐Improved Catalytic Performance for Methanol Oxidation Based on Plasmonic PtAu Dendrites
Authors: Xu Hui , Song Pingping , Wang Jin , Gao Fei , Zhang Yangping , Guo Jun , Du Yukou , Di Junwei
Published: January 2018

Rapid consumption of traditional fossil fuels and increasing energy demand have stimulated attention in utilizing solar energy. However, the lack of highly efficient photocatalysts remains a challenge for their large‐scale development. Plasmonic modification of metallic nanostructures have aroused extensive research interest, which can efficiently convert solar energy into chemical energy. We, herein, design a new class of surface plasmon resonance (SPR) promoted dendritic PtAu photoelectrocatalysts, taking advantage of visible light to enhance the electrocatalytic performances towards methanol oxidation. In virtue of the synergistic effect between Pt and Au, the resultant PtAu dendrites show an unprecedentedly high electrocatalytic activity of 2262.1 mA mg−1 towards methanol oxidation, which is 9.7 times higher than that of the commercial Pt/C. More interestingly, the SPR effect also caused the Pt1Ag1 nanocatalyst under visible‐light irradiation to display a 1.8‐fold enhancement in catalytic activity compared to that under dark conditions, showing great promise for serving as highly efficient photoelectrocatalysts for liquid fuel oxidation and beyond.
Preparation and Characterization of Hydrogenated Castor Oil‐Based Coating Wax
Authors: Huyan Zongyao , Ding Shaoxuan , Yu Xiuzhu , Liu Xiaoli
Published: January 2018

A synthesis method is developed from a reaction between hydrogenated castor oil (HCO) and ethylenediamine to prepare a product to coat paperboard. For highest conversion rate, a molar ratio of 1:3 of HCO and ethylenediamine reacted at 130 °C for 2.5 h. Fourier transform infrared (FTIR) spectroscopy and Nuclear magnetic resonance (NMR) confirm the obtained product is a wax combining HCO with two amide groups. The melting point of the diamide wax is 130 °C. The hardness of the wax is harder than that of other waxes (over eight times to beeswax and over four times to paraffin wax) except carnauba wax. In addition, the cohesiveness of the HCO diamide wax is slightly poorer than that of others. In coating paperboard application, the performance of diamide wax in compression force of all treatments is similar to that of carnauba wax and better than that of other waxes although soaking allows paperboard coated with the wax to have wax loss and compression force loss. The results show that the HCO wax with diamide group can be a good coating material on paperboard.

Practical Applications: The synthesis method is used to prepare a good coating material. The HCO material is confirmed to be diamide wax after structure confirmation by FTIR and NMR. This diamide wax shows good physical properties and plays well in coating paperboard for its high adhesive rate and good compression force with or without soaking or heating. It also shows a good adhesive ability while heating. The application test presents that the HCO‐based diamide wax is good substitute for other wax such as carnauba wax for coating.

A synthesis method by the reaction between hydrogenated castor oil (HCO) and ethylenediamine is used to prepare a coating material. After conducting several attempts, a molar ratio of 1:3 of HCO and ethylenediamine reacted at 130 °C for 2.5 h to acquire the final product. The HCO product is confirmed to be diamide wax after structure confirmation by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The properties of diamide wax are evaluated by texture analyzer and differential scanning calorimetry. By evaluating the coating ability on paperboard, results show that the diamide wax is a good coating material.
Arrayed isoelectric focusing using photopatterned multi‐domain hydrogels
Authors: Yamauchi Kevin A. , Tentori Augusto M. , Herr Amy E.
Published: January 2018

Isoelectric focusing (IEF) is a powerful separation method, useful for resolving subtle changes in the isoelectric point of unlabeled proteins. While microfluidic IEF has reduced the separation times from hours in traditional benchtop IEF to minutes, the enclosed devices hinder post‐separation access to the sample for downstream analysis. The two‐layer open IEF device presented here comprises a photopatterned hydrogel lid layer containing the chemistries required for IEF and a thin polyacrylamide bottom layer in which the analytes are separated. The open IEF device produces comparable minimum resolvable difference in isoelectric point and gradient stability to enclosed microfluidic devices while providing post‐separation sample access by simple removal of the lid layer. Further, using simulations, we determine that the material properties and the length of the separation lanes are the primary factors that affect the electric field magnitude in the separation region. Finally, we demonstrate self‐indexed photomasks for alignment‐free fabrication of multi‐domain hydrogels. We leverage this approach to generate arrayed pH gradients with a total of 80 concurrent separation lanes, which to our knowledge is the first demonstration of multiple IEF separations in series addressed by a single pair of electrodes.
How should we interpret estimates of individual repeatability?
Authors: Wilson Alastair J.
Published: January 2018

Individual repeatability (R), defined as the proportion of observed variance attributable to among-individual differences, is a widely used summary statistic in evolutionarily motivated studies of morphology, life history, physiology and, especially, behaviour. Although statistical methods to estimate R are well known and widely available, there is a growing tendency for researchers to interpret R in ways that are subtly, but importantly, different. Some view R as a property of a dataset and a statistic to be interpreted agnostically with respect to mechanism. Others wish to isolate the contributions of ‘intrinsic’ and/or ‘permanent’ individual differences, and draw a distinction between true (intrinsic) and pseudo-repeatability arising from uncontrolled extrinsic effects. This latter view proposes a narrower, more mechanistic interpretation, than the traditional concept of repeatability, but perhaps one that allows stronger evolutionary inference as a consequence (provided analytical pitfalls are successfully avoided). Neither perspective is incorrect, but if we are to avoid confusion and fruitless debate, there is a need for researchers to recognise this dichotomy, and to ensure clarity in relation to how, and why, a particular estimate of R is appropriate in any case.
STUDIES IN THE GENETICS AND CYTOLOGY OF TWO SPECIES IN THE GENUS ASTER AND THEIR POLYMORPHY IN NATURE
Authors: Wetmore Ralph H. , Delisle Albert L.
Published: January 2018

The following genetical and cytological studies were made in conjunction with investigations in relative growth and morphogenesis (Delisle, 1938) in two species of Aster, A. novae‐angliae L., A. multiflorus Ait.2 and their hybrid. Certain aspects of this work appear significant when considered in relation to the polymorphy of these species and possibly have a bearing on the recognized polymorphy in the genus. A. novae‐angliae is tall, hairy, stout, and relatively unbranched in the young stages, becoming corymbed only at the summit later. It has numerous large, soft, minutely pubescent, lanceolate, acute, entire leaves which are provided with marked auriculations at the base. The bracts of the involucre are loose, erect, nearly equal, glandular‐viscid and linear; the heads are characteristically solitary on individual branchlets; the rays of the type species are violet‐purple and those of the forms roseus (Desf.) Britton and geneseensis. House are rose and white, respectively. This species flowers from August to October, with the bulk of the plants blooming in September.
THE LEAF OF CALYCADENIA AND ITS GLANDULAR APPENDAGES
Authors: Carlquist Sherwin
Published: January 2018

Carlquist, Sherwin. (Rancho Santa Ana Botanic Garden, Claremont, Calif.) The leaf of Calycadenia and its glandular appendages. Amer. Jour. Bot. 46(2) : 70‐80. Illus. 1959.—Large tack‐shaped glands are characteristic of the leaves of Calycadenia which are associated with the inflorescence. These glands may be divided into those which are terminal on leaves and those which occur laterally on the surface of the leaf. Lateral glands show stages early in their development which are identical with those of simpler trichomes of Madinae. Terminal glands, which possess more vascularization of the stalk, show a more modified form of development. Vascularization is not derived from protoderm, but from more deeply‐seated cells. These cells are included in a zone of elongation which forms the stalk. Vascular bundles may extend to the base of glands which lack vascularization in their stalks. Tack‐shaped glands are considered an advanced form of trichome in which internal tissues of the leaf are involved. Within the genus Calycadenia, ontogenetic and comparative studies suggest that the following characters are advanced: reduction to a single terminal gland, “inrolling” of margins to form a cylinder of bundles, concomitant with a central core of fibers or a pectic channel. Systematic distribution of gland occurrence and of types of foliar structure are given.
POLYPLOIDY IN SOUTH AFRICAN SPECIES OF ALOË
Authors: Riley Herbert Parkes
Published: January 2018

Riley, Herbert Parkes (U. Kentucky, Lexington.) Polyploidy in South African species of Aloë. Amer. Jour. Bot. 46(2) : 126‐129. 1959.—Chromosomes were studied from 167 plants of 40 species of Aloë and from 1 unidentified plant; these include 40 plants of A. Davyana growing wild in the Transvaal. In all but 2 plants the diploid complement consisted of 8 long and 6 short chromosomes. The 2 plants of A. ciliaris which were studied were hexaploid with 42 somatic chromosomes. Chromosome counts include 12 species of Aloë from which chromosome numbers apparently had not been determined previously.
INDOLE ACETIC ACID OXIDASE AND PEROXIDASE ACTIVITIES IN NORMAL AND CROWN GALL TISSUE CULTURES OF PARTHENOCISSUS TRICUSPIDATA
Authors: Lipetz Jacques , Galston Arthur W.
Published: January 2018

Lipetz, Jacques, and Arthur W. Galston. (Yale U., New Haven.) Indole acetic acid oxidase and peroxidase activities in normal and crown gall tissue cultures of Parthenocissus tricuspidata. Amer. Jour. Bot. 46(3) : 193‐196. Illus. 1959.—Normal and crown gall cells of P. tricuspidata grown in pure culture were examined for IAA oxidase and peroxidase activities. No IAA oxidase activity could be demonstrated in dialyzed or undialyzed homogenates of either tissue; however, crown gall tissue, but not normal tissue, was found to produce an extracellular IAA oxidase which required Mn++ and DCP as co‐factors. Normal tissue, but not crown gall tissue was found to contain high levels of substances which spared IAA from destruction by a pea IAA oxidase preparation. Peroxidase activity was found to be higher in normal than in crown gall homogenates, but crown gall tissue released considerably more peroxidase into the external medium. The differences in the auxin requirements and growth rate between normal and crown gall cells appear not to be easily explicable in terms of differential auxin destruction.
EFFECTS OF ENVIRONMENT OF PARENT AND GRANDPARENT GENERATIONS ON TUBER PRODUCTION BY POTATOES
Authors: Went F. W.
Published: January 2018

Went, F. W. (Missouri Botanical Garden, St. Louis.) Effects of environment of parent and grandparent generations on tuber production by potatoes. Amer. Jour. Bot. 46(4): 277–282. Illus. 1959.—Potato tubers have very different potentialities of producing tubers on plants of the next generation, according to the growing conditions of the parent plants. When these were grown at cool temperatures, the tuber yield not only of these plants, but also of the following generations, was much higher than when they were grown under warm conditions. Differences in morphology and taste of the tubers as a result of differential temperature treatment of the parent generation are described as well.
NATURE OF THE PLANT COMMUNITY. V. VARIATION WITHIN THE TRUE PRAIRIE COMMUNITY‐TYPE
Authors: McMillan Calvin
Published: January 2018

McMillan, C. (U. Texas, Austin.) Nature of the plant community. V. Variation within the true prairie community‐type. Amer. Jour. Bot. 46(6): 418–424. Illus. 1959.—Population samples of grass species were transplanted to Lincoln, Nebraska, from two grassland communities within the general distribution of the true prairie community‐type. These represented extensive grassland areas near Watertown, South Dakota, and Manhattan, Kansas. True prairie relicts near Colorado Springs, Colorado and in the Black Hills of southwestern South Dakota were also studied in the transplant garden. Only in one species, Stipa spartea Trin., were the transplanted populations essentially similar in behavior. In 8 of the species, Koeleria cristata (L.) Pers., Bouteloua gracilis (H.B.K.) Lag., B. curtipendula (Michx.) Torr., Schizachyrium scoparium Nash, Andropogon gerardi Vitman, Panicum virgatum L., Sorghastrum nutans (L.) Nash, and Sporobolus heterolepis (A. Gray) A. Gray, the Manhattan populations were the latest flowering. In Elymus canadensis L., the Manhattan population was the earliest flowering. The abstraction of two communities into a true prairie type of community with other communities of similar species‐populations is a convenient method for discussing distributional phenomena. However, extreme caution must be used in generalizing about characteristics other than distributional. If the 10 species in the present study were designated by letters, the Watertown and Manhattan communities could be compared ecologically as a b' c d e f g h i j and a b c' d' e' f' g' h' i' j'. The use of taxonomic relationship in vegetational studies is convenient for the reduction of sample size, but the vital aspect of studying variation within the species is in the determination of harmony between vegetation and its habitat. The relict communities are in adjustment with their habitats and represent the results of natural selection in favoring early‐flowering variants within a number of different species. The key to distribution of the true prairie vegetation, widespread or relict, lies in the harmony between a habitat variable and a vegetation variable. Through natural selection, each stand of true prairie may be fundamentally different from any other stand.
COMPARATIVE STUDIES OF FLORAL MORPHOLOGY OF THE LABIATAE
Authors: Hillson Charles J.
Published: January 2018

Hillson, Charles J. (Pennsylvania State U., University Park.) Comparative studies of floral morphology of the Labiatae. Amer. Jour. Bot. 46(6): 451–459. Illus. 1959.—Comparative vascular studies of 39 species of mints from 27 genera reveal 2 basic stelar patterns: those in which the dorsal carpellary bundles are terminal in origin and those in which the dorsal carpellary bundles are basal in origin. Gradations of intermediate dorsal carpellary bundle divergence exist. Steles exhibiting terminal dorsal carpellary bundles are always associated with laminal ovules and are interpreted as being primitive. Marginal ovules are associated with floral steles exhibiting basal divergence of dorsal carpellary bundles and are regarded as being advanced. Adnation of traces seems to be a more reliable character in determining phylogenetic relationships than is connation. On the basis of 3 characters, viz: (1) position of dorsal carpellary bundle divergence, (2) ovule position and (3) degree of concrescence, a phylogenetic series of the 8 sub‐families of Labiatae from advanced to primitive is proffered.
EXPERIMENTAL CONTROL OF FLOWERING IN LEMNA. II. SOME EFFECTS OF MEDIUM COMPOSITION, CHELATING AGENTS AND HIGH TEMPERATURES ON FLOWERING IN L. PERPUSILLA 6746
Authors: Hillman William S.
Published: January 2018

Hillman, William S. (Yale U., New Haven, Conn.) Experimental control of flowering in Lemna. II. Some effects of medium composition, chelating agents and high temperatures on flowering in L. perpusilla 6746. Amer. Jour. Bot. 46(7): 489–495. Illus. 1959.—‐L. perpusilla 6746 flowers as a short‐day plant on Hutner's medium (containing ethylenediaminetetraacetic acid [EDTA]) at constant temperatures from 25 to 30°C., but eventually flowers also in old cultures under 16 or 24 hr. of light. This old‐culture flowering is more pronounced in dilute medium. Flowering is rapid under both long and short days at constant temperatures from 25 to 28°C. in media not containing EDTA; the addition of 10‐5 M EDTA or of similar or higher concentrations of numerous other chelating agents suppresses flowering under long days but not under short (8 hr. light). This effect does not depend on promotion or inhibition of vegetative growth. At 29 to 30°C., a short‐day requirement is manifested even in media permitting flowering under long days at the lower temperatures. Temperatures above 31°C. completely inhibit flowering under all conditions. Brief periods of high temperature given to plants under short‐day conditions inhibit flowering when given during the dark period but not during the light period. The implications of these observations for the further study of flowering are discussed.
A NEW BOWMANITEAN FRUCTIFICATION FROM THE PENNSYLVANIAN OF KANSAS
Authors: Mamay Sergius H.
Published: January 2018

Mamay, Sergius H. (U. S. Geological Survey, Washington, D. C.) A new bowmanitean fructification from the Pennsylvania of Kansas. Amer. Jour. Bot. 46(7): 530–536. Illus. 1959.—A new sphenophyllaceous fructification, Bowmanites moorei sp. nov., is described on the basis of coal ball petrifactions from the Fleming coal in southeastern Kansas. One of the simplest species of Bowmanites, B. moorei has only 3 sporophylls in a whorl. Each sporophyll has 3 lobes, the median one fertile, the 2 lateral ones sterile. Each fertile lobe subtends 2 sporangia, resulting in 6 sporangia in a whorl. The sporangia are inverted, being distally attached to separate sporangiophores that arise in pairs, in axillary positions. The sporangial epidermis and epidermis of the lower surfaces of the sporangiophores are characterized by relatively large, thick‐walled cells. The spores are small, spherical, and trilete, without distinctive ornamentation of the exine. B. moorei adds to the morphological variation known in Bowmanites, but contributes little toward a phylogenetic interpretation of this morphologically complex genus.
RADIATION DAMAGE IN APPLE SHOOT APICES
Authors: Pratt Charlotte , Einset John , Zahur Mohammad
Published: January 2018

Pratt, Charlotte, John Einset, and Mohammad Zahur. (N. Y. S. Agric. Expt. Sta., Geneva.) Radiation damage in apple shoot apices. Amer. Jour. Bot. 46(7): 537–544. Illus. 1959.—Pattern of shoot growth and anatomy of the shoot apex of ‘Golden Delicious’ apple trees on ‘East Malling IX’ rootstock are compared in normal trees and those growing under chronic gamma irradiation (average doses of 17–48 r per 20‐hr. day) at Brookhaven National Laboratory. Bud damage in 6 varieties of apple trees is compared. Irradiated ‘Golden Delicious’ formed lateral buds on the current year's shoot, but the following year these buds grew into spurs which failed to form a terminal bud (“budless” spurs) and enlarged to form “club tips” and “swollen spurs” in this and subsequent years. Cells with thick walls and lightly stained cytoplasm occurred in shoot apices of irradiated lateral buds in mid‐June. The first tunica layer was more resistant to radiation than the inner tunica layers and the corpus; pith rib meristem was still more resistant. Inflorescence and floral meristems were rarely found, but once formed, continued development. One‐year‐old budless spurs had a few leaves but neither an organized apical meristem nor leaf primordia. Surface of the apex was often folded. Periderm and, later, deep‐lying wound cambium developed. Expansion of pith, vascular tissue, cortex, wound cambium and periderm caused enlargement of club tips and swollen spurs. Many lateral buds from the gamma field which were propagated without irradiation in early August grew into long shoots with terminal buds. Scions removed from irradiation in November and inserted into normal trees showed lower survival and many of their shoots were budless. This suggests that the capacity for normal growth of a bud damaged by chronic irradiation is greater in mid‐summer than later in the year. With reference to percentage of budless shoots, ‘Delicious,’ ‘Golden Delicious’ and ‘McIntosh’ were more sensitive to an average dose of 24 r per day and lower doses than were ‘Cox,’ ‘Macoun’ and ‘Spy.’ Symptoms of radiation damage in apple buds during the first year were similar following acute or chronic irradiation. Degree of radiation damage, as expressed by death of apical meristems, was concluded to vary with stage of development of the bud, structure of the apical meristem, and genetic constitution.
ENZYME ACTIVITY AND CELL DIFFERENTIATION IN NEUROSPORA
Authors: Zalokar Marko
Published: January 2018

Zalokar, Marko. (Yale U., New Haven, Conn.) Enzyme activity and cell differentiation in Neurospora. Amer. Jour. Bot, 46(7): 555–559. Illus. 1959.—Morphological differences were observed in vegetative cells of Neurospora of different ages and in different parts of the mycelium. The surface layer of mycelium grown in standing cultures could be separated from the deep layer. The first contained most of the growing hyphae rich in protoplasm, while the second contained heavily vacuolated hyphae laden with fat droplets. Specific activities of several enzymes were studied in conidia, young hyphae, and the surface and deep layers of mature mycelium. Succinic dehydrogenase was low in conidia and about 10 times more active in mature mycelium. The surface layer had twice the activity of the deep layer. Aldolase increased about 3 times after the germination of conidia; it was slightly lower in the surface than in the deep layer of mycelium. Tryptophan synthetase exhibited only small differences between conidia and mycelium and was slightly lower in the surface than in the deep layer. β‐galactosidase was formed in appreciable amounts only after prolonged growth and had a much higher specific activity in the deep layer. The results were discussed in connection with cell differentiation and aging.
THREE CHLOROPHYCEAE FROM ALABAMA SOIL
Authors: Deason Temd R.
Published: January 2018

Deason, Temd R. (U. Texas, Austin.) Three Chlorophyceae from Alabama soil. Amer. Jour. Bot. 46(8): 572–578. Illus. 1959.— Three new algae from Alabama soil are described as follows: Spongiococcum gen. nov., with 2 species, S. tetrasporum sp. nov. and S. alabamense sp. nov. The distinguishing attributes of the genus Spongiococcum are: (1) possession of a sponge‐like plastid; (2) presence of pyrenoids; and (3) Chlamydomonas‐type zoospores. The description of the genus Chlorosarcina Gerneck is emended with respect to zoospore type, and Chlorosarcina stigmatica sp. nov. is described. Cultures of these organisms have been deposited in the Culture Collection of Algae, Department of Botany, Indiana University, Bloomington, Indiana, and herbarium specimens have been sent to the Chicago Natural History Museum, Chicago, Illinois.
EFFECTS OF PURINES, PYRIMIDINES AND RELATED COMPOUNDS UPON CELL FORM IN USTILAGO SPHAEROGENA
Authors: Spoerl Edward , Pullman J. L.
Published: January 2018

Spoerl, Edward, and J. L. Pullman. (U. S. Army Med. Res. Lab., Fort Knox, Ky.) Effects of purines, pyrimidines and related compounds upon cell form in Ustilago sphaerogena. Amer. Jour. Bot. 46(9): 651–656. 1959.—Nucleotide, nucleoside and base constituents of ribosenucleic acid, singly and in combination, were used as nitrogen sources for U. sphaerogena and examined for their effects upon cell form. Combinations of nucleotides, and adenine, produced long cells, i.e., interfered with cell division. A variety of analogues, especially of purine types, was examined for their effects upon cell form. Although adenine produced long cells, a hydroxy group substituted at the 6 position of the purine ring produced short cells. Sulfhydryl, furfurylamino and methyl groups substituted at the 6 position produced long cells. Additional groups and combinations of these groups also were examined. Neither hydroxypurines nor methionine or norleucine, which normally promote short‐cell formation, effectively antagonized the adenine effect, although norleucine tended to counteract a dimercaptopurine effect.
A NEW SPECIES OF ARTHROXYLON (CALAMITACEAE) FROM THE PENNSYLVANIAN OF KANSAS
Authors: Cridland Arthur A.
Published: January 2018

Cridland, Arthur A. (Kansas U., Lawrence.) A new species of Arthroxylon (Calamitaceae) from the Pennsylvanian of Kansas. Amer. Jour. Bot. 46(10): 709–712. Illus. 1959.—Arthroxylon resinaceum sp. nov. is described from 3 specimens found in a coal‐ball collected at West Mineral, Kansas. The tracheids have 1 or 2 rows of pits on the radial walls and the pith cells adjacent to the protoxylem canals are filled with brown contents. Fungus spores are present in the tissues of 1 specimen.
LEAF TEMPERATURES
Authors: Ansari A. Q. , Loomis W. E.
Published: January 2018

Ansari, A. Q., and W. E. Loomis. (Iowa State University, Ames.) Leaf temperatures. Amer. Jour. Bot. 46(10): 713–717. Illus. 1959.—Leaf temperatures were measured with a thermocouple and potentiometer. Readings were taken on leaves of varying thickness, under varying environmental and plant conditions, and during alternating heating and cooling cycles in sun and shade. Leaves tended to assume air temperature. Sunshine heated thin leaves 6–10°C. above the air in about 1 min. Very thick leaves were heated 20°C. above air in 20–30 min. Cooling in still air in shade was at the same rate as heating in sunshine, and the product of this rate times leaf mass in g./cm.2 was constant for all leaves tested. Wind at 5 m.p.h. lowered leaf temperature in the sun about half way to air temperature. This cooling effect can result in a reduction of transpiration by wind. Transpiration had a minor effect on leaf temperature. Wilted leaves showed nearly the same temperature response as turgid ones. Dried leaves heated less and cooled faster in shade than transpiring leaves. Vaselined leaves were 1–3°C. warmer than transpiring leaves but showed similar heating and cooling curves.
INTER‐THALLIC SEXUAL REACTIONS IN ACHLYA, A GENUS OF THE AQUATIC FUNGI
Authors: Barksdale Alma Whiffen
Published: January 2018

Barksdale, Alma Whiffen. (New York Botanical Garden, New York.) Inter‐thallic sexual reactions in Achlya, a genus of the aquatic fungi. Amer. Jour. Bot. 47(1): 14—23. Illus. 1960.– Inter‐thallic sexual reactions, involving the coöperative induction of sexual organs, have been found to occur between members of homothallic, as well as heterothallic species of the sub‐genus Achlya. The induction of sexual organs, both on single thalli and on paired thalli, is temperature‐dependent. Sexual organs were initiated at 15°—20°C. in 14 of 27 heterothallic strains that were usually sterile at 25°. The hermaphroditic sexual organs were like those of either A. ambisexualis or A. bisexualis in 19 strains; like those of A. prolifera in 3 strains; like those of A. inflata in 1 strain; and like those of A. americana in 1 strain. In some instances, the sexual reaction between paired thalli was complete at 20°C. but incomplete (i.e., oospores were not formed) at 25°C. The heterothallic and homothallic strains studied could be assigned to 1 of 12 (6 female and 6 male) inter‐action types, on the basis of their sexual responses. These sexual types are characterized and their possible usefulness in indicating kinship among species of Achlya is assessed. The possible origin of heterothallic from homothallic forms of Achlya is discussed.
CHROMOSOME NUMBERS IN UMBELLIFERAE. II
Authors: Bell C. Ritchie , Constance Lincoln
Published: January 2018

Bell, C. Ritchie (U. of North Carolina, Chapel Hill.), and Lincoln Constance. Chromosome Numbers in Umbelliferae. II. Amer. Jour. Bot. 47(1) : 24‐32. Illus. 1960.–Chromosome numbers are reported for plants representing an additional 100 taxa of Umbelliferae. Chromosome numbers for 77 of these taxa are published here for the first time, previously published chromosome numbers of 19 taxa are verified, and numbers differing from those previously published are reported in 4 instances. Ten of the genera included here have been previously unknown cytologically. Polyploidy has been discovered in Bowlesia and confirmed in Pimpinella. Aneuploid series appear to occur in Eremocharis, Eryngium, Oenanthe, Perideridia, and Ptilimnium. Every chromosome count is referable to a cited herbarium specimen.
THE CULTURE COLLECTION OF ALGAE AT INDIANA UNIVERSITY
Authors: Starr Richard C.
Published: January 2018

Starr, Richard C. (Indiana U., Bloomington.) The Culture Collection of Algae at Indiana University. Amer. Jour. Bot. 47(1) : 67–86. 1960.–A list is presented of cultures of algae available for purposes of research and teaching. The list includes 592 Chlorophyta; 77 Chrysophyta; 56 Cyanophyta; 55 Euglenophyta; 6 Rhodophyta; 1 Phaeophyta; 2 residual flagellates. Formulae of culture media and directions for maintaining the cultures are included as are instructions for evoking sexual reproduction in species of Chlamydomonas, Pandorina, Eudorina, Volvox, Cosmarium, Clostcrium, Oedogonium, Bulbochaete and Vaucheria.
LIGHT AND ELECTRON MICROSCOPE STUDIES OF THE PRIMARY XYLEM OF RICINUS COMMUNIS
Authors: Scott Flora Murray , Sjaholm Virginia , Bowler Edwin
Published: January 2018

Scott, Flora Murray, Virginia Sjaholm, and Edwin Bowler (U. California, Los Angeles.) Light and electron microscope studies of the primary xylem of Ricinus communis. Amer. Jour. Bot. 47(3) : 162‐173. Illus. 1960.–The development of annular and spiral vessels in Ricinus communis has been examined under light and electron miscroscopes. Under the light microscope it is seen that spiral elements make up the bulk of the primary xylem. Pits and plasmodesmata are ubiquitous and are demonstrable in vertical and end walls. Plasmodesmata are evident in spiral thickenings. During tissue growth, intercellular spaces are formed between surrounding cells and developing vessels. These circum‐vessel spaces are first lined with and later occluded by suberinlike substances. Traces of a material similar in microchemical reaction are laid down in the middle lamella. A suberin‐like lining, termed in this paper the lipid lining, stainable with dimethylaminoazobenzene, occurs in mature living vessel elements. Innumerable minute fat‐like droplets, refringent, and stainable with Sudan III, Sudan Black and also with osmic acid, occur in the outer cytoplasm and appear to be attached to the vessel lining by fine protoplasmic strands. They presumably are the source of the wall deposits. After the death of the protoplast, the vessel walls appear completely suberized. When contiguous cells are removed by treatment with I2ki‐H2SO4, their site and the site of the intercellular spaces remain marked by linear suberized ridges on the vessel wall. Annular and spiral thickenings arise as cellulose strands and begin to lignify only when the vessel reaches maximum diameter. In transverse section, the broken end of an extracted spiral thickening appears stratified. Under the electron microscope, pits and plasmodesmata are evident in procambial and in differentiating xylem elements in all walls. Annular and spiral thickening are distinguishable first as closely woven microfibrillar cellulose bands. As lignin is deposited in the microfibrillar mesh, the thickenings become dense to the electron beam. Irradiation with the full strength of the electron beam distinguishes between spiral thickenings in younger and older vessels. Older spirals remain apparently unchanged. Younger spirals instantly swell, volatilize in part, and assume a moniliform outline. The bead‐like swellings consist of a matrix partly transparent to the electron beam and an internal framework of a material comparatively dense to the electron beam. Similar intense irradiation differentiates between younger and older vessel linings. Older linings appear unchanged, while the younger react violently, volatilize in part and stabilize as an irregular coagulum set in a basic mesh. The volatilized substances appear as granules on lining surface or on substrate. The changing microfibrillar pattern of the cell wall is observed from the procambial stage to the final deposition of the lipid vessel lining.
THE CHROMOSOMES OF SPLNACIA OLERACEA
Authors: Ellis J. R. , Janick Jules
Published: January 2018

Ellis, J. R., and Jules Janick. (Purdue U., Lafayette, Ind.) The chromosomes of Spinaeia oleracea. Amer. Jour. Bot. 47(3) : 210—214. Illus. 1960.—The somatic chromosomes of S. oleracea are described and each has been associated with one of the 6 morphological trisomics derived from triploid‐diploid crosses. Of these 6 primary trisomies, reflex had been shown by genetic studies to be trisomic for the chromosomes carrying the sex‐determining factors. This chromosome is the longest of the somatic complement and has a sub‐median centromere. No obvious heteromorphism of this chromosome pair was observed in staminate plants. Heteromorphism involving this chromosome pair has been reported recently in 2 varieties of cultivated spinach by Zoschke (1956) and Dressier (1958) and was earlier reported by Araratjan (1939) for the wild species, S. tetandra. However, their accounts differ markedly from each other and with the present results in respect to the morphology of this chromosome pair. This study suggests the existence of races which differ with respect to the morphology of the chromosome pair containing the X Y factors.
THE ZYGOSPORIC STAGE OF THE GENUS PIRELLA (MUCORACEAE)
Authors: Hesseltine C. W.
Published: January 2018

Hesseltine, C. W. (Northern Utilization Research and Development Division, Peoria, Ill.) The zygosporic stage of the genus Pirella (Mucoraceae). Amer. Jour. Bot. 47(3) : 225—230. Illus. 1960.–Pirella circinans Bainier has been found to be heterothallic. The zygospores, which have never before been reported, are formed when + and – strains are mated at 15°C. on such media as tomato paste‐oatmeal or potato dextrose agars. Zygospores are formed in a diffuse manner in the aerial mycelium and are similar to those found in the genus Mucor. The single species, P. circinans, is described on a synthetic medium and its synonyms are listed. It is believed to represent a genus between Mucor and the family Thamnidiaceae.
THE COMPOSITION OF THE DEVELOPING PRIMARY WALL IN ONION ROOT TIP CELLS. II. CYTOCHEMICAL LOCALIZATION
Authors: Jensen William A.
Published: January 2018

Jensen, William A. (U. California, Berkeley.) The composition of the developing primary wall in onion root tip cells. II. Cytochemical localization. Amer. Jour. Bot. 47(4) : 287—295. Illus. 1960.–The composition of the developing cell wall in the first 2 mm. of the onion root tip was studied using a cytochemical technique that permitted the detection of hemicellulose and the noncellulosic polysaccharides as well as the pectic substances and cellulose. The technique is based on the combination of a differential extraction procedure with the periodic acid‐Schiff reaction for carbohydrates. The data obtained indicate that the cells of the apical initials are low in all wall substances but that all of the wall materials are present to some extent. Early in cell development, differences appear in the composition of the walls of the various tissues. The cortical cells are relatively high in the noncellulosic polysaccharides and cellulose while relatively low in the pectic substances and hemicellulose. Very early in development the protoderm is similar to the cortex, but differences develop during the radial enlargement of the cells. During this stage the walls of the protodermal cells are low in the noncellulosic polysaccharides and cellulose and high in pectic substances and hemicellulose. As elongation progresses, these differences are lost and the 2 tissues become very similar. The vascular cell walls are low in the noncellulosic polysaccharides and cellulose and are high in pectic substances and hemicellulose early in development. Later, hemicellulose becomes relatively more important. When the cell wall materials are sequentially extracted, no change in the general morphology of the cell occurs until only the noncellulosic polysaccharides and the cellulose remained. When the noncellulosic polysaccharides are then removed, the cells remain intact but are 30% less in diameter. This suggests that while cellulose is of critical importance, the noncellulosic polysaccharides may play a major role in determining the physical characteristics of the wall.
HYBRIDIZATION AND INTROGRESSION IN THE GRASS GENUS ELYMUS
Authors: Brown Walter V. , Pratt Gene A.
Published: January 2018

Brown, W. V., and G. A. Pratt. (U. Texas, Austin.)Hybridization and introgression in the grass genus Elymus.Amer. Jour. Bot. 47 (8) : 669–676. Illus. 1960.—The production of artificial F1hybrids that produce some seed betweenE. virginicusandE. canadensis, E. virginicusandE. interruptus, andE. canadensisandE. interruptusproves that similar plants found in nature are true hybrids. The artificial hybrids constituted the basis of comparison in an analysis of natural local populations in the Austin region. Analysis by scatter diagrams indicates that there is introgression of genes of some species into the genomes of others through the development of hybrid swarms. In the area studied the great variability ofvirginicusis due to the introgression ofcanadensisand, possibly,interruptusgenes. Such hybridization and subsequent introgression have occurred many times and in many places and are still taking place. It is likely that the named varieties ofcanadensisandvirginicusmay be introgressant types that are the results of hybridizations between those species and others that occur sympatrically in Eastern United States.
BIOSYSTEMATICS OF TWO PERENNIAL SPECIES OF HELIANTHUS (COMPOSITAE). I. CROSSING RELATIONSHIPS AND TRANSPLANT STUDIES
Authors: Long Robert W.
Published: January 2018

Long, Robert W. (Ohio Wesleyan U., Delaware.) Biosystematics of two perennial species of Helianthus (Compositae). I. Crossing relationships and transplant studies. Amer. Jour. Bot. 47(9) : 729–735. Illus. 1960.–The objective of this investigation has been to clarify the genetic relationships of H. giganteus and H. grosseserratus using hybridization experiments, transplant studies, and related biosystematic techniques. The species are morphologically related and are common in the southern Great Lakes region. They are homoploid with n = 17. Two groups of ecological races were identified within each species and generally they are all cross‐fertile. Helianthus giganteus and H. grosseserratus should be termed ecotypes; apparently they are elements of a large diploid complex (ecospecies) composed of at least 4 taxonomic species.