scholarly journals XII. On the ascent of sap

1895 ◽  
Vol 186 ◽  
pp. 563-576 ◽  
Keyword(s):  
Careful Examination ◽  
Root Pressure

Many theories have been formed to account for the ascent of sap in high trees, when root pressure is not acting. All have been found, on careful examination, unsatisfactory. Our attention was particularly directed to the problem as we were together in Bonn, in the Summer of 1893, when Professor E. Strasburger was kind enough to show us some of his experiments on the question, and since then we have, at intervals, occupied ourselves with some considerations as to the cause of the ascent of liquids in trees. It was not, however, till late last Spring that we had leisure to enter definitely on the research. We wish to acknowledge the kindness of Professor E. Perceval Wright in giving us the benefit of his advice on all occasions, and also the advantage we derived from Professor G. F. FitzGerald’s suggestive ideas.

Microstructural Variations in Melt-Spun Rapidly Solidified Ribbons

1985 ◽  
Vol 43 ◽  
pp. 54-55
Author(s):  
L. A. Bendersky ◽  
W. J. Boettinger
Keyword(s):  
Solid State ◽  
Processing Parameters ◽  
Heat Extraction ◽  
Solid State Reactions ◽  
Careful Examination ◽  
Ion Milling ◽  
Melt Spun ◽  
Wheel Side ◽  
Rapidly Solidified ◽  
Heat Extraction Rate

Rapid solidification produces a wide variety of sub-micron scale microstructure. Generally, the microstructure depends on the imposed melt undercooling and heat extraction rate. The microstructure can vary strongly not only due to processing parameters changes but also during the process itself, as a result of recalescence. Hence, careful examination of different locations in rapidly solidified products should be performed. Additionally, post-solidification solid-state reactions can alter the microstructure.The objective of the present work is to demonstrate the strong microstructural changes in different regions of melt-spun ribbon for three different alloys. The locations of the analyzed structures were near the wheel side (W) and near the center (C) of the ribbons. The TEM specimens were prepared by selective electropolishing or ion milling.

Crystal structure-size relationship in ultrafine metallic particles

1989 ◽  
Vol 47 ◽  
pp. 266-267
Author(s):  
Jun Liu ◽  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Ultrafine Particles ◽  
Carbon Film ◽  
Lattice Defects ◽  
Careful Examination ◽  
Seeded Growth ◽  
Gold Particles ◽  
Metallic Particles ◽  
Interfacial Structures ◽  
Typical Particle ◽  
Many Particles

Ultrafine particles usually have unique physical properties. This study illustrates how the lattice defects and interfacial structures between particles are related to the size of ultrafine crystalline gold particles.Colloidal gold particles were produced by reducing gold chloride with sodium citrate at 100°C. In this process, particle size can be controlled by changing the concentration of the reactant. TEM samples are prepared by transferring a small amount of solution onto a thin (5 nm) carbon film which is suspended on a copper grid. In this work, all experiments were performed with Philips 430T at 300 kV.With controlled seeded growth, particles of different sizes are produced, as shown in Figure 1. By a careful examination, it can be resolved that very small particles have lattice defects with complex interfaces. Some typical particle structures include multiple twins, resulting in a five-fold symmetry bicrystals, and highly disordered regions. Many particles are too complex to be described by simple models.

The Complexity of Health Disparities: More Than Just Black–White Differences

2021 ◽  
pp. 1-10
Author(s):  
Charles Ellis ◽  
Molly Jacobs
Keyword(s):  
Health Disparities ◽  
Clinical Outcomes ◽  
The United States ◽  
Careful Examination ◽  
White Americans ◽  
Speech Language Pathology ◽  
Death Rates ◽  
The Social ◽  
Health Related ◽  
Language Pathology

Health disparities have once again moved to the forefront of America's consciousness with the recent significant observation of dramatically higher death rates among African Americans with COVID-19 when compared to White Americans. Health disparities have a long history in the United States, yet little consideration has been given to their impact on the clinical outcomes in the rehabilitative health professions such as speech-language pathology/audiology (SLP/A). Consequently, it is unclear how the absence of a careful examination of health disparities in fields like SLP/A impacts the clinical outcomes desired or achieved. The purpose of this tutorial is to examine the issue of health disparities in relationship to SLP/A. This tutorial includes operational definitions related to health disparities and a review of the social determinants of health that are the underlying cause of such disparities. The tutorial concludes with a discussion of potential directions for the study of health disparities in SLP/A to identify strategies to close the disparity gap in health-related outcomes that currently exists.

Investigation into Cigarette Smoking and Atmospheric Pollution in the Aetiology of Lung Cancer

1963 ◽  
Vol 2 (01) ◽  
pp. 13-19 ◽  
Author(s):  
R. Doll
Keyword(s):  
Lung Cancer ◽  
Cigarette Smoking ◽  
Atmospheric Pollution ◽  
Direct Evidence ◽  
Retrospective Studies ◽  
Common Factor ◽  
Animal Experiments ◽  
Smoking Habits ◽  
Careful Examination ◽  
Ancillary Data

The evidence that cigarette smoking and atmospheric pcllution are causes of lung cancer is largely statistical. The first evidence was indirect; that is, i1. was noticed that in many countries the incidence of lung cancer had increased and that the increase could be correlated with changes in the prevalence of cigarette smoking and of certain types of atmospheric pollution.Since then much direct evidence has been obtained. The relationship between cigarette smoking and lung cancer has been demonstrated retrospectively by comparing the smoking habits of patients with and without lung cancer and prospectively by observing the mortality from lung cancer in groups of persons of known smoking habits. Conclusions can be drawn from these studies only after careful examination of the results. In particular it is important in retrospective studies to test a) the reproducibility of the data, b) the representativeness of the data, and c) the comparability of the special series and their controls. The resul1.s of retrospective studies are all similar and all show a close relationship between cigarette smoking and the disease.The results have been confirmed by pro~pective studies which are lesF. open to bias. The results can be explained if cigarette smoking causes lung cancer or if both are related to some third common factor. Ancillary data (pathological changes in the bronchial mucosa, animal experiments, etc.) support the causal hypothesis.The evidence relating to atmospheric pollution is less definite and it is difficult to get direct evidence of a relationship in the individual. It is clear that pollution has little effect in the absence of smoking, but the mortality associated with a given amount of smoking is generally greater in large towns than in the countryside and among men who have emigrated from Britain than among men who have lived all their lives in less polluted countries.

Pre-Linnaean pictures of the secretarybird, Sagittarius serpentarius (J. F. )

2008 ◽  
Vol 35 (2) ◽  
pp. 243-251 ◽  
Author(s):  
RAGNAR K. KINZELBACH
Keyword(s):  
Nineteenth Century ◽  
Sub Saharan Africa ◽  
Careful Examination ◽  
Nile Valley ◽  
Rain Forests ◽  
Roman Emperor ◽  
Persian Language ◽  
The Family ◽  
Other Information ◽  
Sub Saharan

The secretarybird, the only species of the family Sagittariidae (Falconiformes), inhabits all of sub-Saharan Africa except the rain forests. Secretarybird, its vernacular name in many languages, may be derived from the Arabic “saqr at-tair”, “falcon of the hunt”, which found its way into French during the crusades. From the same period are two drawings of a “bistarda deserti” in a codex by the Holy Roman Emperor Frederick II (1194–1250). The original sketch obviously, together with other information on birds, came from the court of Sultan al-Kâmil (1180–1238) in Cairo. Careful examination led to an interpretation as Sagittarius serpentarius. Two archaeological sources and one nineteenth century observation strengthened the idea of a former occurrence of the secretarybird in the Egyptian Nile valley. André Thevet (1502–1590), a French cleric and reliable research traveller, described and depicted in 1558 a strange bird, named “Pa” in Persian language, from what he called Madagascar. The woodcut is identified as Sagittarius serpentarius. The text reveals East Africa as the real home of this bird, associated there among others with elephants. From there raises a connection to the tales of the fabulous roc, which feeds its offspring with elephants, ending up in the vernacular name of the extinct Madagascar ostrich as elephantbird.

Troubling Figures

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Logan Natalie O'Laughlin
Keyword(s):  
Critical Discourse Analysis ◽  
Science Studies ◽  
Critical Discourse ◽  
People Of Color ◽  
Careful Examination ◽  
Environmental Toxicants ◽  
Environmental Racism ◽  
Feminist Science Studies ◽  
Feminist Science ◽  
Do So

This essay examines the figure of the pesticide-exposed intersex frog, a canary in the coal mine for public endocrinological health. Through feminist science studies and critical discourse analysis, I explore the fields that bring this figure into being (endocrinology, toxicology, and pest science) and the colonial and racial logics that shape these fields. In so doing, I attend to the multiple nonhuman actors shaping this figure, including the pesky weeds and insects who prompt pesticides’ very existence, “male” frogs who function as test subjects, and systemic environmental racism that disproportionately exposes people of color to environmental toxicants. I encourage careful examination of galvanizing environmental figures like this toxic intersex frog and I offer a method to do so.

The Demand For Money in Pakistan: Reply (Notes and Comments)

1975 ◽  
Vol 14 (3) ◽  
pp. 370-375
Author(s):  
M. A. Akhtar
Keyword(s):  
Interest Rates ◽  
Money Demand ◽  
Strong Support ◽  
Physical Capital ◽  
Careful Examination ◽  
Demand For Money ◽  
Weak Support ◽  
Complementarity Hypothesis ◽  
The Difference ◽  
The One

I am grateful to Abe, Fry, Min, Vongvipanond, and Yu (hereafter re¬ferred to as AFMVY) [1] for obliging me to reconsider my article [2] on the demand for money in Pakistan. Upon careful examination, I find that the AFMVY results are, in parts, misleading and that, on the whole, they add very little to those provided in my study. Nevertheless, the present exercise as well as the one by AFMVY is useful in that it furnishes us with an opportunity to view some of the fundamental problems involved in an empi¬rical analysis of the demand for money function in Pakistan. Based on their elaborate critique, AFMVY reformulate the two hypo¬theses—the substitution hypothesis and the complementarity hypothesis— underlying my study and provide us with some alternative estimates of the demand for money in Pakistan. Briefly their results, like those in my study, indicate that income and interest rates are important in deter¬mining the demand for money. However, unlike my results, they also suggest that the price variable is a highly significant determinant of the money demand function. Furthermore, while I found only a weak support for the complementarity between money demand and physical capital, the results obtained by AFMVY appear to yield a strong support for that rela¬tionship.1 The difference in results is only a natural consequence of alter¬native specifications of the theory and, therefore, I propose to devote most of this reply to the criticisms raised by AFMVY and the resulting reformulation of the two mypotheses.

Slurs, Assertion, and Predication

2019 ◽  
pp. 286-305
Author(s):  
Christopher Hom
Keyword(s):  
Careful Examination ◽  
Conventional Implicature ◽  
Literal Truth ◽  
Truth Conditional

A multidimensional account of the meanings of slurs holds that a slur has both literal, truth-conditional content (which is neutral) and conventional implicature (which is derogatory). This chapter offers a careful examination of the motivations and commitments for a multidimensional account and argues that the theoretic costs for such a view are prohibitive. One of the primary motivations for a multidimensional account over a purely truth-conditional account is the apparent wide-scoping phenomenon of slurs (e.g., that derogatory content does not seem cancellable under negation). The chapter argues that carefully distinguishing between predication and assertion not only dispels the misconception that the phenomena in question is centrally about scope but also vindicates the purely truth-conditional account as a more general and unified explanation.

scholarly journals Grapevine species from varied native habitats exhibit differences in embolism formation/repair associated with leaf gas exchange and root pressure

2015 ◽  
Vol 38 (8) ◽  
pp. 1503-1513 ◽  
Author(s):  
THORSTEN KNIPFER ◽  
ASHLEY EUSTIS ◽  
CRAIG BRODERSEN ◽  
ANDREW M. WALKER ◽  
ANDREW J. MCELRONE
Keyword(s):  
Gas Exchange ◽  
Leaf Gas Exchange ◽  
Root Pressure ◽  
Native Habitats

Herpesvirus-Associated Proliferative Skin Disease in Frogs and Toads: Proposed Pathogenesis

2021 ◽  
pp. 030098582110063
Author(s):  
Francesco C. Origgi ◽  
Patricia Otten ◽  
Petra Lohmann ◽  
Ursula Sattler ◽  
Thomas Wahli ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Rana Temporaria ◽  
Skin Lesions ◽  
Bufo Bufo ◽  
Careful Examination ◽  
Altered Expression ◽  
Expression Of Genes ◽  
Cell Remodeling ◽  
Tissue Changes

A comparative study was carried out on common and agile frogs ( Rana temporaria and R. dalmatina) naturally infected with ranid herpesvirus 3 (RaHV3) and common toads ( Bufo bufo) naturally infected with bufonid herpesvirus 1 (BfHV1) to investigate common pathogenetic pathways and molecular mechanisms based on macroscopic, microscopic, and ultrastructural pathology as well as evaluation of gene expression. Careful examination of the tissue changes, supported by in situ hybridization, at different stages of development in 6 frogs and 14 toads revealed that the skin lesions are likely transient, and part of a tissue cycle necessary for viral replication in the infected hosts. Transcriptomic analysis, carried out on 2 naturally infected and 2 naïve common frogs ( Rana temporaria) and 2 naturally infected and 2 naïve common toads ( Bufo bufo), revealed altered expression of genes involved in signaling and cell remodeling in diseased animals. Finally, virus transcriptomics revealed that both RaHV3 and BfHV1 had relatively high expression of a putative immunomodulating gene predicted to encode a decoy receptor for tumor necrosis factor in the skin of the infected hosts. Thus, the comparable lesions in infected frogs and toads appear to reflect a concerted epidermal and viral cycle, with presumptive involvement of signaling and gene remodeling host and immunomodulatory viral genes.

Sign in / Sign up

Export Citation Format

Share Document