1,724,541 research outputs found
[Elandslaagte Colliery, S. Africa, Engine Drawing Card, Sketch No. 7724]
No full textThis engine drawing card was created for Elandslaagte Colliery, Class 6-28 D. Section H-6-D. Sketch 7724. Copy Spec. 25F-247
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The implications of the reclassification of South African wildlife species as farm animals
Full text linkCITATION: Somers, M. J. et al. 2020. The implications of the reclassification of South African wildlife species as farm animals. South African Journal of Science, 116(1/2):7724, doi:10.17159/sajs.2020/7724.The original publication is available at https://sajs.co.zaThe Government Gazette No. 42464 dated 17 May 20191 amended Table 7 of the Animal Improvement Act (Act no. 62
of 1998), which lists breeds of animals, to include at least 32 new wild animal species, including 24 indigenous
mammals. The list includes threatened and rare species such as cheetah, white and black rhinoceros, and suni. Some
alien species such as lechwe, various deer species and rabbits are also included. The cornerstone of the original Act
is ‘To provide for the breeding, identification and utilisation of genetically superior animals to improve the production
and performance of animals in the interest of the Republic; and to provide for matters connected therewith.’
By declaring these wild animals as landrace breeds (in Table 7 of the regulations), the Act implies that they are
locally developed breeds. The Act typically provides for landrace breeds to be bred and ‘genetically improved’ to
obtain superior domesticated animals with enhanced production and performance. Similarly, provision is made
for the Breeders Association to lay claim to the breed and to establish specific breed standards for animals to be
included in stud books. Animals declared as landrace breeds can also be used for genetic manipulation, embryo
harvesting, in-vitro fertilisation and embryo transfers. As indigenous species of wildlife are included in the recent
amendment to the Act, the amendment is flawed.
Here we point out numerous concerns in the new legislation, including the process of consultation, and argue
that the law will not improve the genetics of the species mentioned but will have considerable negative genetic
consequences and pose ecological and economic risks. We also suggest that this new law is in direct conflict with
other biodiversity laws in South Africa.https://sajs.co.za/article/view/7724Publisher's versio
Еstimation of cytotoxic activity of lectin-like substance of B.subtilis B-7724 in system in vitro
No full textМета:
оцінка in vitro цитотоксичної дії на пухлинні та імунокомпетентні клітини лектину, виділеного з фільтрату культуральної рідини Bacillus subtilis В-7724 за модифікованим методом.
Об’єкт і методи:
лектиноподібну речовину (ЛПР) отримували із культуральної рідини В. subtilis В-7724 після 10-
добового культивування на
стандартизованому середовищі Гаузе. Досліджували in vitro цитотоксичну активність
ЛПР проти клітин пухлинних (раку Ерліха, меланоми В16, А549, К562)
або умовно нормальних (MDBK) клітинних ліній, а також клітин імунокомпетентних органів інтактних мишей лінії Balb/c. Оцінку цитотоксичного впливу проводили, використовуючи цитоморфологічний аналіз
за допомогою світлового мікроскопа та колориметричний МТТ-тест.
Статистичну обробку результатів проводили за загальноприйнятими
методами. Вірогідність різниці між контрольними та дослідними вимірами оцінювали за t-критерієм Стьюдента.
Результати:
ЛПР, виділена з середовища росту мікроорганізму B. subtilis В-7724, виявляє дозозалежну цитотоксичну активність щодо клітин різних модельних пухлин:
мінімальну активність виявляє в концентрації 0,02
мг/мл, максимальну
— 0,1
мг/мл. Серед клітин перевивних пухлинних ліній найбільш чутливою виявилася меланома В16: індекс цитотоксичності (ІЦ) становив 72,3% (0,02
мг/мл) та 97,2% (0,04
мг/мл). Практично нечутливими до цитотоксичної дії ЛПР були клітини лінії К562: ІЦ = 13,4%
(0,02
мг/мл) та 22,3% (0,04
мг/мл). Серед клітин імунокомпетентних органів найбільш чутливими до дії ЛПР виявилися клітини тимуса. Більш резистентні клітини макрофагальної ланки: додавання ЛПР
в концентрації 0,02
мг/мл практично не мало цитотоксичного впливу:
через 60
хв ІЦ = 14,8%, через 24
год — 60,9%. Імунотоксичну дію виявляла концентрація ЛПР 0,1
мг/мл (ІЦ 90,2–99,5%).
Висновок:
концентрації ЛПР 0,02–0,04
мг/мл у подальшому можуть бути використані
в дослідах in vivo як такі, що володіють цитотоксичною активністю
щодо пухлинних клітин, але водночас не мають суттєвої імунотоксичної дії. Одержані результати можуть стати підґрунтям для вдосконалення напрямків і методів використання ЛПР B. subtilis B-7724 в онкологічній клінічній практиці.Objective:
in vitro evaluation of cytotoxic activity in relation to tumor cells of various lines and immunotoxic activity of lectin-like substance (LLS) isolated from the culture liquid medium filtrate of В. subtilis
В-7724 by the modified method.
Object and methods:
LLS was obtained from the culture medium B. subtilis
B-7724, after 10-day cultivation on a standardized medium. The in vitro cytotoxic activity of LLS was investigated in relation to tumor cells (Ehr
lich cancer, melanoma B16, A549, K562) or conditionally normal (MDBK)
cell lines, as well as cells of the immune-competent organs of Balb/c intact mice. The evaluation of the cytotoxic effect was performed using a cytomorphological analysis using a light microscope and a colorimetric MTT test. The wells with culture medium and target
cells, which did not add the test drug, served as control.
Statistical processing of the results was carried out according to commonly accepted methods. The probability of the diffe
rence between control and experimental
measurements was estimated by the Student t-criterion.
Results:
LLS isolated from the growth medium of the
microorganism В. subtilis В-7724, detects dose-dependent cytotoxic activity in relation to cells of various model tumors: the minimum activity is found at a concentration of 0.02
mg/ml, maximum — 0.1
mg/ml. Among the cells of transplantable tumor lines, the melanoma
B16: cytotoxic index (CI) = 72.3 (0.02
mg/ml) and
97.2% (0.04 mg/ml) was the most sensitive. The cells
of the K562
line: CI = 13.4 (0.02
mg/ml) and 22.3%
(0.04 mg/ml) were virtually insensitive to the LLS of the
cytotoxic action. Among the cells of the immunocompetent organs, the most sensitive to the action of LLS were
thymus cells. More resistant macrophage cells: adding
LLS at a concentration of 0.02
mg/ml practically did not
have a cytotoxic effect: after 60
minutes CI = 14.8%,
after 24
hours — 60.9%. Immunotoxic effect showed
a concentration of LLS 0.1
mg/ml (CI
= 90.2–99.5%).
Conclusion:
LLS concentrations of 0.02–0.04
mg/ml
can be used subsequently in vivo experiments as having
cytotoxic activity against tumor cells, but at the same
time, have no significant immunotoxic activity. The obtained results can form the basis for improving the directions and methods of using В.
subtilis В-7724 LLS
in oncology clinical practice
Еstimation of cytotoxic activity of lectin-like substance of B.subtilis B-7724 in system in vitro
No full textМета:
оцінка in vitro цитотоксичної дії на пухлинні та імунокомпетентні клітини лектину, виділеного з фільтрату культуральної рідини Bacillus subtilis В-7724 за модифікованим методом.
Об’єкт і методи:
лектиноподібну речовину (ЛПР) отримували із культуральної рідини В. subtilis В-7724 після 10-
добового культивування на
стандартизованому середовищі Гаузе. Досліджували in vitro цитотоксичну активність
ЛПР проти клітин пухлинних (раку Ерліха, меланоми В16, А549, К562)
або умовно нормальних (MDBK) клітинних ліній, а також клітин імунокомпетентних органів інтактних мишей лінії Balb/c. Оцінку цитотоксичного впливу проводили, використовуючи цитоморфологічний аналіз
за допомогою світлового мікроскопа та колориметричний МТТ-тест.
Статистичну обробку результатів проводили за загальноприйнятими
методами. Вірогідність різниці між контрольними та дослідними вимірами оцінювали за t-критерієм Стьюдента.
Результати:
ЛПР, виділена з середовища росту мікроорганізму B. subtilis В-7724, виявляє дозозалежну цитотоксичну активність щодо клітин різних модельних пухлин:
мінімальну активність виявляє в концентрації 0,02
мг/мл, максимальну
— 0,1
мг/мл. Серед клітин перевивних пухлинних ліній найбільш чутливою виявилася меланома В16: індекс цитотоксичності (ІЦ) становив 72,3% (0,02
мг/мл) та 97,2% (0,04
мг/мл). Практично нечутливими до цитотоксичної дії ЛПР були клітини лінії К562: ІЦ = 13,4%
(0,02
мг/мл) та 22,3% (0,04
мг/мл). Серед клітин імунокомпетентних органів найбільш чутливими до дії ЛПР виявилися клітини тимуса. Більш резистентні клітини макрофагальної ланки: додавання ЛПР
в концентрації 0,02
мг/мл практично не мало цитотоксичного впливу:
через 60
хв ІЦ = 14,8%, через 24
год — 60,9%. Імунотоксичну дію виявляла концентрація ЛПР 0,1
мг/мл (ІЦ 90,2–99,5%).
Висновок:
концентрації ЛПР 0,02–0,04
мг/мл у подальшому можуть бути використані
в дослідах in vivo як такі, що володіють цитотоксичною активністю
щодо пухлинних клітин, але водночас не мають суттєвої імунотоксичної дії. Одержані результати можуть стати підґрунтям для вдосконалення напрямків і методів використання ЛПР B. subtilis B-7724 в онкологічній клінічній практиці.Objective:
in vitro evaluation of cytotoxic activity in relation to tumor cells of various lines and immunotoxic activity of lectin-like substance (LLS) isolated from the culture liquid medium filtrate of В. subtilis
В-7724 by the modified method.
Object and methods:
LLS was obtained from the culture medium B. subtilis
B-7724, after 10-day cultivation on a standardized medium. The in vitro cytotoxic activity of LLS was investigated in relation to tumor cells (Ehr
lich cancer, melanoma B16, A549, K562) or conditionally normal (MDBK)
cell lines, as well as cells of the immune-competent organs of Balb/c intact mice. The evaluation of the cytotoxic effect was performed using a cytomorphological analysis using a light microscope and a colorimetric MTT test. The wells with culture medium and target
cells, which did not add the test drug, served as control.
Statistical processing of the results was carried out according to commonly accepted methods. The probability of the diffe
rence between control and experimental
measurements was estimated by the Student t-criterion.
Results:
LLS isolated from the growth medium of the
microorganism В. subtilis В-7724, detects dose-dependent cytotoxic activity in relation to cells of various model tumors: the minimum activity is found at a concentration of 0.02
mg/ml, maximum — 0.1
mg/ml. Among the cells of transplantable tumor lines, the melanoma
B16: cytotoxic index (CI) = 72.3 (0.02
mg/ml) and
97.2% (0.04 mg/ml) was the most sensitive. The cells
of the K562
line: CI = 13.4 (0.02
mg/ml) and 22.3%
(0.04 mg/ml) were virtually insensitive to the LLS of the
cytotoxic action. Among the cells of the immunocompetent organs, the most sensitive to the action of LLS were
thymus cells. More resistant macrophage cells: adding
LLS at a concentration of 0.02
mg/ml practically did not
have a cytotoxic effect: after 60
minutes CI = 14.8%,
after 24
hours — 60.9%. Immunotoxic effect showed
a concentration of LLS 0.1
mg/ml (CI
= 90.2–99.5%).
Conclusion:
LLS concentrations of 0.02–0.04
mg/ml
can be used subsequently in vivo experiments as having
cytotoxic activity against tumor cells, but at the same
time, have no significant immunotoxic activity. The obtained results can form the basis for improving the directions and methods of using В.
subtilis В-7724 LLS
in oncology clinical practice
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
