scholarly journals The regulation of respiration in the flea, xenopsylla cheopis , Roths. (Pulicidea)

1935 ◽  
Vol 118 (810) ◽  
pp. 397-419 ◽  
Keyword(s):  
Diffusion Control ◽  
Regulation Of Respiration ◽  
Tracheal System ◽  
Xenopsylla Cheopis ◽  
The Common ◽  
Pass Through ◽  
Terrestrial Insects ◽  
Opening And Closing ◽  
The Tropics ◽  
Mechanical Aeration

The gaseous exchanges of terrestrial insects are regulated by (i) the opening and closing of the spiracles—the “diffusion control” of Hazelhoff (1926, 1927)—and, in the larger and more active forms by (ii) the mechanical aeration of the tracheal system by pumping movements—“ventilation control.” Spiracular and pumping movements may occur at the same time; for example, in those insects in which a directed stream of air is driven through the main tracheal branches (Fraenkel, 1932; McGovran, 1931); and then the spiracles, by allowing air to pass through them in one direction only, are believed to play a part in the mechanism of ventilation. The object of the present work was to study in greater detail than hitherto the spiracular movements of an insect in which these are not complicated by mechanical ventilation. For this purpose the common rat flea of the tropics, Xenopsylla cheopis , has proved an ideal subject.

The Seasonal Habit of the common Anophelines of Nyasaland, with a Note on its Relation to the Seasonal Incidence of Malaria

1925 ◽  
Vol 15 (4) ◽  
pp. 361-376 ◽  
Author(s):  
W. A. Lamborn
Keyword(s):  
Food Plants ◽  
Seasonal Prevalence ◽  
East African ◽  
Seasonal Incidence ◽  
Temperature Variations ◽  
The Common ◽  
Terrestrial Insects ◽  
The Tropics ◽  
Vegetable Material ◽  
Main Factor

It is an early experience of the Field Entomologist in the Tropics, whether his work lies in countries such as the East African Protectorates, which have well defined seasons, or where the seasons are less clearly marked, as in the Federated Malay States, that a seasonal prevalence of the commoner insects is quite as definite as it is in the Temperate regions. Outside the Tropics the main factor determining prevalence would seem to be suitability of temperature, but in the Tropics, where temperature variations may be slight, moisture is the controlling factor. Purely terrestrial insects which feed, whether as larvae or imagos wholly on vegetable material, breed and are most abundant at such times as the food-plants are at their best, that is when, as the result of favourable conditions of temperature and moisture, there is a full flow of tissue-building sap. The law of seasonal prevalence is valid also for many insects whose imagos derive their food directly from the larger animals, a source of supply available at all seasons. For these insects, too, the same conditions hold good, but affect chiefly the larvae.

scholarly journals O BEM COMUM COMO VALOR E O ACESSO À JUSTIÇA COMO COMPROMISSO: IMPLICAÇÕES SOBRE O PROCESSO CIVIL

2020 ◽  
Vol 1 (58) ◽  
pp. 410
Author(s):  
Janaína Machado STURZA ◽  
Karinne Emanoela Goettems dos SANTOS
Keyword(s):  
Social Life ◽  
Common Good ◽  
Transformation Process ◽  
Fundamental Rights ◽  
Access To Justice ◽  
The Common Good ◽  
Civil Process ◽  
The Common ◽  
Pass Through ◽  
Judicial Procedures

RESUMO Objetivo: Este estudo tem como objetivo fomentar a reflexão sobre o atual cenário de conflitos sociais, no qual se encontra a sociedade contemporânea, destacando a importância do acesso à Justiça por meio de um processo civil constitucionalmente adequado, na perspectiva do bem comum. Metodologia: A pesquisa converge para a importância da adaptação dos procedimentos judiciais à realidade social, por meio de um estudo bibliográfico norteado pelo método hipotético dedutivo, apresentando a hermenêutica filosófica gadameriana e as perspectivas de Mauro Cappelletti como principais referenciais teóricos. Resultados: Entender a sociedade a partir de um contexto conflituoso implica assumir uma nova postura diante da complexidade social e da efetivação do necessário processo de transformação na perspectiva de bem comum e, essencialmente, de acesso à Justiça como compromisso. Na órbita do processo civil, esse compromisso torna-se ainda mais evidente com a superveniência do novo Código de Processo. Contribuições: A demonstração de que a efetividade dos direitos fundamentais e a consagração da cidadania perpassam necessariamente por um processo civil constitucionalmente adequado, o qual deve e é capaz de adaptar-se às complexidades da vida social contemporânea.Palavras-chave: bem comum; cidadania; acesso à Justiça; processo constitucionalmente adequado.  ABSTRACT Objective: To encourage reflection on the current scenario of social conflicts in which contemporary society is situated, highlighting the importance of access to Justice by way of a constitutionally adequate civil process in the perspective of the common good. Methodology: The research converges to the importance of adapting judicial procedures to social reality by way of a bibliographic study guided by the hypothetical deductive method, presenting Gadamerian philosophical hermeneutics and the perspectives of Mauro Cappelletti as main theoretical references. Results: To understand the society from a conflictual context implies taking a new stance before social complexity and the implementation of the necessary transformation process in the perspective of the common good and, essentially, access to Justice as a commitment. In the orbit of civil proceedings this commitment becomes even more evident upon the supervenience of the new Code of Procedure.Contributions: The demonstration that the effectiveness of fundamental rights and the implementation of citizenship necessarily pass through a constitutionally adequate civil process, which must and is capable of adapting to the complexities of contemporary social life. Keywords: Common good; citizenship; access to Justice; appropriate constitutional process.

scholarly journals A family of quadrics

1938 ◽  
Vol 5 (4) ◽  
pp. 207-210
Author(s):  
L. M. Brown
Keyword(s):  
General Position ◽  
Common Part ◽  
The Family ◽  
The Common ◽  
Pass Through

In a recent paper I have discussed the families of quadrics in [2n] which are obtained by causing the members to have the greatest possible number of fixed [n – 1]'s or “generators.” It was found possible to fix four [n – 1]'s in general position; the family of quadrics through these possessed a “base” variety, common to all the members, which consisted of a highly degenerate Vn–1. Here I consider the same problem for quadrics in [2n + 1], find how many generators may be assigned arbitrarily and discuss the common part of the quadrics which pass through such generators.

scholarly journals Beliefs and Consumer Search in a Vertical Industry

2019 ◽  
Vol 18 (5) ◽  
pp. 2359-2393 ◽  
Author(s):  
Maarten Janssen ◽  
Sandro Shelegia
Keyword(s):  
Low Cost ◽  
Search Costs ◽  
Retail Price ◽  
Consumer Search ◽  
Common Assumption ◽  
Vertical Relations ◽  
Retail Prices ◽  
The Common ◽  
Search Market ◽  
Pass Through

Abstract This paper studies vertical relations in a search market. As the wholesale arrangement between a manufacturer and its retailers is typically unobserved by consumers, their beliefs about who is to be blamed for a price deviation play a crucial role in determining wholesale and retail prices. The common assumption in the consumer search literature is that consumers exclusively blame an individual retailer for a price deviation. We show that in the vertical relations context, predictions based on this assumption are not robust in the sense that if consumers hold the upstream manufacturer at least partially responsible for the deviation, equilibrium predictions are qualitatively different. For robust beliefs, the vertical model can explain a variety of observations, such as retail price rigidity (or, alternatively, low cost pass-through), nonmonotonicity of retail prices in search costs, and (seemingly) collusive retail behavior. The model can be used to study a monopoly online platform that sells access to final consumers.

Simulation of growth and development of diverse legume species in APSIM

2002 ◽  
Vol 53 (4) ◽  
pp. 429 ◽  
Author(s):  
M. J. Robertson ◽  
P. S. Carberry ◽  
N. I. Huth ◽  
J. E. Turpin ◽  
M. E. Probert ◽  
...  
Keyword(s):  
Growth And Development ◽  
Independent Set ◽  
Sowing Date ◽  
Legume Species ◽  
Physiological Basis ◽  
Simulation Accuracy ◽  
Crop Models ◽  
Medicago Sativa L ◽  
The Common ◽  
The Tropics

This paper describes the physiological basis and validation of a generic legume model as it applies to 4 species: chickpea (Cicer arietinum L.), mungbean (Vigna radiata (L.) Wilczek), peanut (Arachis hypogaeaL.), and lucerne (Medicago sativa L.). For each species, the key physiological parameters were derived from the literature and our own experimentation. The model was tested on an independent set of experiments, predominantly from the tropics and subtropics of Australia, varying in cultivar, sowing date, water regime (irrigated or dryland), row spacing, and plant population density. The model is an attempt to simulate crop growth and development with satisfactory comprehensiveness, without the necessity of defining a large number of parameters. A generic approach was adopted in recognition of the common underlying physiology and simulation approaches for many legume species. Simulation of grain yield explained 77, 81, and 70% of the variance (RMSD = 31, 98, and 46 g/m2) for mungbean (n = 40, observed mean = 123 g/m2), peanut (n = 30, 421 g/m2), and chickpea (n = 31, 196 g/m2), respectively. Biomass at maturity was simulated less accurately, explaining 64, 76, and 71% of the variance (RMSD = 134, 236, and 125 g/m2) for mungbean, peanut, and chickpea, respectively. RMSD for biomass in lucerne (n = 24) was 85 g/m2 with an R2 of 0.55. Simulation accuracy is similar to that achieved by single-crop models and suggests that the generic approach offers promise for simulating diverse legume species without loss of accuracy or physiological rigour.

Dynamics of tracheal compression in the horned passalus beetle

2013 ◽  
Vol 304 (8) ◽  
pp. R621-R627 ◽  
Author(s):  
James S. Waters ◽  
Wah-Keat Lee ◽  
Mark W. Westneat ◽  
John J. Socha
Keyword(s):  
Dynamical Behavior ◽  
The Body ◽  
Reverse Direction ◽  
Effective Diameter ◽  
Contrast Imaging ◽  
Tracheal System ◽  
Tracheal Compression ◽  
Internal Mixing ◽  
Respiratory Gases ◽  
Opening And Closing

Rhythmic patterns of compression and reinflation of the thin-walled hollow tubes of the insect tracheal system have been observed in a number of insects. These movements may be important for facilitating the transport and exchange of respiratory gases, but observing and characterizing the dynamics of internal physiological systems within live insects can be challenging due to their size and exoskeleton. Using synchrotron X-ray phase-contrast imaging, we observed dynamical behavior in the tracheal system of the beetle, Odontotaenius disjunctus. Similar to observations of tracheal compression in other insects, specific regions of tracheae in the thorax of O. disjunctus exhibit rhythmic collapse and reinflation. During tracheal compression, the opposing sides of a tracheal tube converge, causing the effective diameter of the tube to decrease. However, a unique characteristic of tracheal compression in this species is that certain tracheae collapse and reinflate with a wavelike motion. In the dorsal cephalic tracheae, compression begins anteriorly and continues until the tube is uniformly flattened; reinflation takes place in the reverse direction, starting with the posterior end of the tube and continuing until the tube is fully reinflated. We report the detailed kinematics of this pattern as well as additional observations that show tracheal compression coordinated with spiracle opening and closing. These findings suggest that tracheal compression may function to drive flow within the body, facilitating internal mixing of respiratory gases and ventilation of distal regions of the tracheal system.

scholarly journals Enhanced Security Methods of Door Locking Based Fingerprint

2020 ◽  
Vol 9 (3) ◽  
pp. 1173-1178 ◽  
Keyword(s):  
Liquid Crystal Display ◽  
Security System ◽  
Alarm System ◽  
The People ◽  
Web Camera ◽  
Monitoring Camera ◽  
Arduino Microcontroller ◽  
Pass Through ◽  
Opening And Closing ◽  
Lcd Displays

This paper presents an enhanced methodology in implementing and designing a security system for door locking purpose based on fingerprint, GSM technology, monitoring camera, alarm system and password system. This security system will provide enough security by limiting unauthorized people access and taking a record of those who pass through it. Sometimes unauthorized people or burglars try to break the door for evil intentions at a time when no one is available at a targeted place, so this paper introduces some security solutions for that problem and they are the main contribution of our paper. We introduce an alarm system to alert the people at the surroundings, GSM module that’s used to send an SMS message to the registered user’s (responsible person) and a web camera that’s used to take a video for a person who tries to break the lock, password keypad that’s used after fingerprint sensing to provide extra security. Definitely the registered users are the only persons who can access the lock, and the door closes after five seconds from the opening time. The method used to implement this experiment involves the use of a fingerprint scanner R305 that’s interfaced with Arduino microcontroller-ATMEGA328P to control the locking and unlocking process of a door. During all the opening and closing processes, the16x2 Liquid Crystal Display (LCD) displays some commands which can be used to instruct the users like, place your finger on the sensor, the door is opened, the door is closed, the message is sent, please enter the password etc. If an unregistered user tries to access the door using their fingerprints, automatically his/her access is denied. The proposed door lock security system is can be used at homes, offices, banks, hospitals, and in other governmental and private sectors. Our proposed system was tested in real-time and has shown competitive results compared to other projects using RFI and password.

Larvae of Ceratophyllus wickhami and other Species of Fleas

Parasitology ◽  
1930 ◽  
Vol 22 (2) ◽  
pp. 242-259 ◽  
Author(s):  
Enid K. Sikes
Keyword(s):  
Life History ◽  
Seventeenth Century ◽  
Instar Larva ◽  
Grey Squirrel ◽  
Experimental Conditions ◽  
Tracheal System ◽  
Xenopsylla Cheopis ◽  
The Third ◽  
History Of ◽  
Third Instar Larva

A short historical account is given of the writings on flea larvae since the seventeenth century. The larvae have been known since Leeuwenhoek tried to breed them in 1683.The life-history of Ceratophyllus wickhami is described. The fleas were bred in the laboratory on a grey squirrel. Three larval instars occur, and the life-history occupies, on an average, 6 weeks under experimental conditions.The external anatomy of the third instar larva of C. wickhami is described. The mouth parts are generalised and suggest the condition of a primitive insect. The tracheal system is composed of a double longitudinal trunk on each side, with spiracles on the prothorax, metathorax and first eight abdominal segments.The first and second instar of C. wickhami are similar to the third instar larvae, except in size and the presence of a hatching spine in the first stage.The larva of Ceratophyllus fasciatus is mentioned. The importance of the species lies in the presence of completely separated galea and lacinia.Larvae of Xenopsylla cheopis and X. astia are briefly described. The larvae of the two species are practically identical except for the shape of the mandibles.

scholarly journals Modulation of the slow/common gating of CLC channels by intracellular cadmium

2015 ◽  
Vol 146 (6) ◽  
pp. 495-508 ◽  
Author(s):  
Yawei Yu ◽  
Ming-Feng Tsai ◽  
Wei-Ping Yu ◽  
Tsung-Yu Chen
Keyword(s):  
Binding Site ◽  
Transmembrane Domain ◽  
Kinetic Studies ◽  
Dimer Interface ◽  
State Dependent ◽  
Fast Gating ◽  
Cl Channels ◽  
The Common ◽  
The Individual ◽  
Opening And Closing

Members of the CLC family of Cl− channels and transporters are homodimeric integral membrane proteins. Two gating mechanisms control the opening and closing of Cl− channels in this family: fast gating, which regulates opening and closing of the individual pores in each subunit, and slow (or common) gating, which simultaneously controls gating of both subunits. Here, we found that intracellularly applied Cd2+ reduces the current of CLC-0 because of its inhibition on the slow gating. We identified CLC-0 residues C229 and H231, located at the intracellular end of the transmembrane domain near the dimer interface, as the Cd2+-coordinating residues. The inhibition of the current of CLC-0 by Cd2+ was greatly enhanced by mutation of I225W and V490W at the dimer interface. Biochemical experiments revealed that formation of a disulfide bond within this Cd2+-binding site is also affected by mutation of I225W and V490W, indicating that these two mutations alter the structure of the Cd2+-binding site. Kinetic studies showed that Cd2+ inhibition appears to be state dependent, suggesting that structural rearrangements may occur in the CLC dimer interface during Cd2+ modulation. Mutations of I290 and I556 of CLC-1, which correspond to I225 and V490 of CLC-0, respectively, have been shown previously to cause malfunction of CLC-1 Cl− channel by altering the common gating. Our experimental results suggest that mutations of the corresponding residues in CLC-0 change the subunit interaction and alter the slow gating of CLC-0. The effect of these mutations on modulations of slow gating of CLC channels by intracellular Cd2+ likely depends on their alteration of subunit interactions.

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