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1.
Bull Entomol Res ; : 1-9, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639207

RESUMEN

Lateralisation is a well-established phenomenon observed in an increasing number of insect species. This study aims to obtain basic details on lateralisation in courtship and mating behaviour in Ostrinia furnacalis, the Asian corn borer. We conducted laboratory investigations to observe lateralisation in courtship and mating behaviours in adult O. furnacalis. Our goal was also to detect lateralised mating behaviour variations during sexual interactions and to elucidate how these variances might influence the mating success of males. Our findings reveal two distinct lateralised traits: male approaches from the right or left side of the female and the direction of male turning displays. Specifically, males approaching females from their right side predominantly exhibited left-biased 180° turning displays, while males approaching females from the left-side primarily displayed right-biased 180° turning displays. Notably, left-biased males, executing a 180° turn for end-to-end genital contact, initiated copulation with fewer attempts and began copulation earlier than their right-biased approaches with left-biased 180° turning displays. Furthermore, mating success was higher when males subsequently approached the right side of females during sexual encounters. Left-biased 180° turning males exhibited a higher number of successful mating interactions. These observations provide the first report on lateralisation in the reproductive behaviour of O. furnacalis under controlled laboratory conditions and hold promise for establishing reliable benchmarks for assessing and monitoring the quality of mass-produced individuals in pest control efforts.

2.
Environ Entomol ; 52(6): 970-982, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37715511

RESUMEN

The Asian corn borer (Ostrinia furnacalis, Lepidoptera, Crambidae) and Oriental armyworm (Mythimna separata, Lepidoptera, Noctuidae) are 2 major lepidopteran pests of the maize plant, especially the whorls and tassels. The aim of this study was to investigate competition between 2 lepidopteran pests of maize. Intraspecific and interspecific competition occurs when O. furnacalis and M. separata larvae interact with various stages of the maize plant. Therefore, determining whether this competition can decrease larval damage by causing adverse effects on larval growth is crucial. During the maize growing season of 2022, the interaction of these species was assessed in the experimental field of Jilin Agricultural University, China. Interspecific and intraspecific competition of larvae in different maize tissues and the influence of competition on larval development was determined in the fields. The results showed that first, probing behavior was significantly frequent in O. furnacalis larvae; intraspecific and interspecific attack was significant at 4th instar (with leaf, silk, and kernel). Interspecific defense behavior was significant at 3rd instar (without food). O. furnacalis larvae showed attack behavior toward M. separata larvae frequently. Second, competition increased the mortality rate of O. furnacalis larvae (intraspecific, 67%; interspecific, 33%) and decreased pupation emergence rate. Thus, intraspecific and interspecific competition might affect the competitive displacement of pest species sharing the same ecological niche, as well as the prevalence and population dynamics of pests, and help to develop integrated pest management strategies.


Asunto(s)
Mariposas Nocturnas , Humanos , Animales , Larva , Dinámica Poblacional , Zea mays , China
3.
Sensors (Basel) ; 23(6)2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36991986

RESUMEN

Blockchain technology in the healthcare industry has potential to enable enhanced privacy, increased security, and an interoperable data record. Blockchain technology is being implemented in dental care systems to store and share medical information, improve insurance claims, and provide innovative dental data ledgers. Because the healthcare sector is a large and ever-growing industry, the use of blockchain technology would have many benefits. To improve dental care delivery, researchers advocate using blockchain technology and smart contracts due to their numerous advantages. In this research, we concentrate on blockchain-based dental care systems. In particular, we examine the current research literature, pinpoint issues with existing dental care systems, and consider how blockchain technology may be used to address these issues. Finally, the limitations of the proposed blockchain-based dental care systems are discussed which may be regarded as open issues.


Asunto(s)
Cadena de Bloques , Tecnología , Privacidad , Atención a la Salud , Seguridad Computacional
4.
Nanoscale ; 14(30): 10910-10917, 2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35851391

RESUMEN

Transparent semiconductor oxides with two-dimensional (2D) heterostructures have been extensively studied as new materials for thin-film transistors and photosensors due to their remarkable photovoltaic characteristics, making them useful for newly developed optoelectronics. Here we demonstrate the fabrication and characterization of an ITO/n-IGZO/p-GeSe transparent selective wavelength photodetector. The wavelength-dependent photovoltaic behavior of the n-IGZO/p-GeSe heterostructure under UV-Visible laser light shifts the I-V curves down with positive Voc and negative Isc values of about 0.12 V and -49 nA and 0.09 V and -17 nA, respectively. Interestingly, when an NIR laser irradiated the device, the I-V curves shifted up with negative Voc and positive Isc values of about -0.11 V and 45 nA, respectively. This behavior is attributed to the free carrier concentration induced by photogenerated carriers across the device at different points that varied with the wavelength-dependent photon absorption. Consequently, the direction of the electric field polarity across the junction can be flipped. This study demonstrates a zero-bias near-infrared (NIR) photodetector with a high photoresponsivity of 538.9 mA W-1, a fast rise time of 25.2 ms, and a decay time of 25.08 ms. Furthermore, we observed a detectivity (D) of 8.4 × 109 Jones, a normalized photocurrent to dark current ratio (NPDR) of 2.8 × 1010 W-1, and a noise equivalent power (NEP) of 2.2 × 10-14 W Hz-1/2. Our strategy opens alternative possibilities for scalable, low-cost, multifunctional transparent near-infrared photosensors with selective wavelength photodetection.

5.
Environ Sci Pollut Res Int ; 29(35): 53718-53736, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35290585

RESUMEN

Climate change is bringing drastic changes to the food availability, accessibility, quality, and stability in the world. Pakistan heavily relies on production of wheat for food security. This study investigates the role of climate change on food security over Punjab regions, Pakistan, from 1979-2020. The study utilized the total production of wheat to measure food security. Moreover, the study utilized mean, maximum, minimum temperature, wind speed, and rainfall as a measurement of climate change. This study utilized auto-regressive distributed lag (ARDL) bound test cointegration approach to test the long-run cointegration, while ARDL model is applied to investigate the short-run relationship among modeled variables. This study adopted Augmented Dicky Fuller (ADF) and Phillips Parron (PP) test to check the stationarity of the data. Moreover, the study ensures reliability and validity of the model by utilizing Breusch-Godfrey serial correlation, Breusch-Pagan-Godfry HSK, and Ramsey RESET test. This study found that wheat cultivated area (0.46*), total irrigated area (2.67***), total un-irrigated area (1.93***), and total area sown ([1.0809**) have a positive and significant long-run impact on food production in all regions of Punjab Pakistan. However, while average, the maximum and minimum temperature is negatively and significantly associated with food production in all regions of Punjab (- 1.07**; - 3.33***; - 1.84**), except northern Punjab, where maximum temperature affects positively food production Punjab. Rainfall negatively and significantly affects food production in northern (- 0.34**) and central and southern (- 0.13***) Punjab. Furthermore, wind speed negatively affects food production in all regions of Punjab (- 0.22**; - 0.21*; - 0.11**), except northern Punjab. This study implies that government should develop policies to increase irrigation facilities and loan facilities to increase the total area sown that will help to increase wheat yield and ensure food security. Moreover, the government should devise policies for large-scale plantations to minimize climate change impacts. The study also suggests new improved varieties of the wheat crop that can survive and flourish in the presence of adverse climatic changes, high temperature, and high wind speed.


Asunto(s)
Cambio Climático , Desarrollo Económico , Agricultura , Seguridad Alimentaria , Pakistán , Reproducibilidad de los Resultados , Triticum
6.
Sensors (Basel) ; 21(23)2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34883933

RESUMEN

Internet of Vehicles (IoV) has emerged as an advancement over the traditional Vehicular Ad-hoc Networks (VANETs) towards achieving a more efficient intelligent transportation system that is capable of providing various intelligent services and supporting different applications for the drivers and passengers on roads. In order for the IoV and VANETs environments to be able to offer such beneficial road services, huge amounts of data are generated and exchanged among the different communicated entities in these vehicular networks wirelessly via open channels, which could attract the adversaries and threaten the network with several possible types of security attacks. In this survey, we target the authentication part of the security system while highlighting the efficiency of blockchains in the IoV and VANETs environments. First, a detailed background on IoV and blockchain is provided, followed by a wide range of security requirements, challenges, and possible attacks in vehicular networks. Then, a more focused review is provided on the recent blockchain-based authentication schemes in IoV and VANETs with a detailed comparative study in terms of techniques used, network models, evaluation tools, and attacks counteracted. Lastly, some future challenges for IoV security are discussed that are necessary to be addressed in the upcoming research.

7.
Sci Rep ; 11(1): 3688, 2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33574562

RESUMEN

Two-dimensional (2D) heterostructure with atomically sharp interface holds promise for future electronics and optoelectronics because of their multi-functionalities. Here we demonstrate gate-tunable rectifying behavior and self-powered photovoltaic characteristics of novel p-GeSe/n-MoSe2 van der waal heterojunction (vdW HJ). A substantial increase in rectification behavior was observed when the devices were subjected to gate bias. The highest rectification of ~ 1 × 104 was obtained at Vg = - 40 V. Remarkable rectification behavior of the p-n diode is solely attributed to the sharp interface between metal and GeSe/MoSe2. The device exhibits a high photoresponse towards NIR (850 nm). A high photoresponsivity of 465 mAW-1, an excellent EQE of 670%, a fast rise time of 180 ms, and a decay time of 360 ms were obtained. Furthermore, the diode exhibits detectivity (D) of 7.3 × 109 Jones, the normalized photocurrent to the dark current ratio (NPDR) of 1.9 × 1010 W-1, and the noise equivalent power (NEP) of 1.22 × 10-13 WHz-1/2. The strong light-matter interaction stipulates that the GeSe/MoSe2 diode may open new realms in multi-functional electronics and optoelectronics applications.

8.
Nanoscale ; 11(33): 15596-15604, 2019 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-31403638

RESUMEN

The fundamental unit of the nervous system is a synapse, which is involved in transmitting information between neurons as well as learning, memory, and forgetting processes. Two-terminal memristors can fulfil most of these requirements; however, their poor dynamic changes in resistance to input electric stimuli remain an obstacle, which must be improved for accurate and quick information processing. Herein, we demonstrate the synaptic properties of ZnO-based memristors, which were significantly enhanced (∼340 times) by geometrical modulation due to the localized electric field enhancement. Specifically, by inserting Ag-nanowires and Ag-dots into the ZnO/Si interface, the resistive switching could be controlled from a digital to analog mode. A finite element simulation revealed that the presence of Ag could enhance the localized electric field, which in turn improved the migration of ionic species. Further, the device showed a variety of comprehensive synaptic functions, for instance, paired-pulse facilitation and transformation from short-term plasticity to long-term plasticity, including the Pavlovian associative learning process in a human brain. Our study presents a novel architecture to enhance the synaptic sensitivity, and its uses in practical applications, including the artificial learning algorithm.


Asunto(s)
Algoritmos , Electricidad , Nanocables/química , Silicio/química , Plata/química , Sinapsis/fisiología , Óxido de Zinc/química
9.
Small ; 15(10): e1804346, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30721568

RESUMEN

ZnO is a potential candidate for photodetection utilizing the pyroelectric effect. Here, a self-biased and translucent photodetector with the configuration of Cu4 O3 /ZnO/FTO/Glass is designed and fabricated. In addition, the pyroelectric effect is effectively harvested using indium tin oxide (ITO), silver nanowires (AgNWs), and a blend of AgNWs-coated ITO as the transparent selective contact electrode. The improved rise times are observed from 1400 µs (bare condition; without the selective electrode) to 69, 60, 7 µs, and fall times from 720 µs (bare condition) to 80, 70, 10 µs for corresponding ITO, AgNWs, and AgNWs-coated ITO contact electrodes, respectively. Similarly, the responsivity and detectivity are enhanced by about 4.39 × 107 and 5.27 × 105 %, respectively. An energy band diagram is proposed to explain the underlying working mechanism based on the workfunction of the ITO (4.7 eV) and AgNWs (4.57 eV) as measured by Kelvin probe force microscopy, which confirms the formation of type-II band alignment resulting in the efficient transport of photogenerated charge carriers. The functional use of the transparent selective contact electrode can effectively harness the pyro-phototronic effect for next-generation transparent and flexible optoelectronic applications.

10.
ACS Appl Mater Interfaces ; 10(40): 34370-34376, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30207159

RESUMEN

The neuromorphic system processes enormous information even with very low energy consumption, which practically can be achieved with photonic artificial synapse. Herein, a photonic artificial synapse is demonstrated based on an all-oxide highly transparent device. The device consists of conformally grown In2O3/ZnO thin films on a fluorine-doped tin oxide/glass substrate. The device showed a loop opening in current-voltage characteristics, which was attributed to charge trapping/detrapping. Ultraviolet illumination-induced versatile features such as short-term/long-term plasticity and paired-pulse facilitation were truly confirmed. Further, photonic potentiation and electrical habituation were implemented. This study paves the way to develop a device in which current can be modulated under the action of optical stimuli, serving as a fundamental step toward the realization of low-cost synaptic behavior.

11.
ACS Appl Mater Interfaces ; 10(17): 14292-14298, 2018 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-29668257

RESUMEN

We report a self-biased and transparent Cu4O3/TiO2 heterojunction for ultraviolet photodetection. The dynamic photoresponse improved 8.5 × 104% by adding silver nanowires (AgNWs) Schottky contact and maintaining 39% transparency. The current density-voltage characteristics revealed a strong interfacial electric field, responsible for zero-bias operation. In addition, the dynamic photoresponse measurement endorsed the effective holes collection by embedded-AgNWs network, leading to fast rise and fall time of 0.439 and 0.423 ms, respectively. Similarly, a drastic improvement in responsivity and detectivity of 187.5 mAW-1 and of 5.13 × 109 Jones, is observed, respectively. The AgNWs employed as contact electrode can ensure high-performance for transparent and flexible optoelectronic applications.

12.
J Knee Surg ; 30(8): 793-797, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28086244

RESUMEN

The purpose of this randomized study was to compare clinical and surgical outcomes of total knee replacements (TKRs) in the early postoperative period using midvastus approach versus medial parapatellar approach in Asian population in a double blind manner. Forty-two knees each were operated using midvastus approach and the medial parapatellar approach. Clinical parameters that were evaluated included Knee Society score (KSS); knee pain using visual analogue scale (VAS) on day 1, 1 week, and 1 month; time required to straight leg raise (SLR); patellar tracking; mean extensor lag at 1 week and 1 month; and time of discharge from the hospital. Surgical parameters that were evaluated included tourniquet time, incidence of lateral retinacular release, estimated blood loss, and any complications during the surgery. KSS at 1 week and 1 month postoperatively were significantly higher in the midvastus group as compared with medial parapatellar group; though similar at 3 months, 6 months, and 1 year. The patients in midvastus group required fewer number of lateral retinacular releases; achieved SLR earlier; had less mean extensor lag at 1 week; had less mean VAS score at day 1, 1 week, and 1 month; and had shorter hospital stay. There was no significant difference in the mean tourniquet time and estimated blood loss. One patient had patellar maltracking in the medial parapatellar group as compared with none in midvastus group. Midvastus approach to TKR results in quicker functional recovery with early discharge and rehabilitation in the Asian population as compared with medial parapatellar approach.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Articulación de la Rodilla/cirugía , Anciano , Pueblo Asiatico , Pérdida de Sangre Quirúrgica , Método Doble Ciego , Femenino , Humanos , Tiempo de Internación , Masculino , Osteoartritis de la Rodilla/cirugía , Recuperación de la Función , Escala Visual Analógica
13.
Indian J Orthop ; 49(3): 289-99, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26015628

RESUMEN

BACKGROUND: Diffusion tensor imaging (DTI) is based upon the phenomenon of water diffusion known as "Brownian motion." DTI can detect changes in compressed spinal cord earlier than magnetic resonance imaging and is more sensitive to subtle pathological changes of the spinal cord. DTI observation in compressed and noncompressed spinal cord in tuberculosis (TB) spine is not described. This study presents observations in Pott's spine patients with or without neural deficit. MATERIALS AND METHODS: Thirty consecutive cases of TB spine with mean age of 32.1 years of either sexes with paradiscal lesion, with/without paraplegia divided into two groups: Group A: (n = 15) without paraplegia and group B: (n = 15) with paraplegia were evaluated by DTI. The average fractional anisotropy (FA) and mean diffusivity (MD) values were calculated at 3 different sites, above the lesion (SOL)/normal, at the lesion and below SOL for both groups and mean was compared. Visual impression of tractography was done to document changes in spinal tracts. RESULTS: The mean canal encroachment in group A was 39.60% and group B 44.4% (insignificant). Group A mean FA values above SOL, at the lesion and below SOL were 0.608 ± 0.09, 0.554 ± 0.14, and 0.501 ± 0.16 respectively. For group B mean FA values above SOL, at the lesion and below SOL were 0.628 ± 0.09, 0.614 ± 0.12 and 0.487 ± 0.15 respectively. There was a significant difference in mean FA above the SOL as compared to the mean FA at and below SOL. P value above versus below the SOL was statistically significant for both groups (0.04), but P value for at versus below the SOL (0.01) was statistically significant only in group B. On tractography, disruption of fiber tract at SOL was found in 14/15 (93.3%) cases of group A and 14/15 cases (93.3%) of group B (6/6 grade 4, 3/3 grade 3 and 5/6 grade 2 paraplegic cases). CONCLUSION: The FA and MD above the lesion were same as reported for healthy volunteer hence can be taken as control. FA increases, and MD decreases at SOL in severe grade of paraplegia because of epidural collection while in milder grade, both decrease. In group A (without neurological deficit), mean FA and MD in patients with and without canal encroachment was similar. On tractography, both groups A and B (with or without neurological deficit) showed disruption of fiber tract at SOL and thickness of distally traced spinal cord was appreciably less than the upper cord. FA and MD could not differentiate between various grades of paraplegia. Although the number of patients in each group are small.

14.
J Pak Med Assoc ; 59(3): 136-40, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19288936

RESUMEN

OBJECTIVE: To estimate size of injection drug users (IDU), determine their high risk behaviours and assess the prevalence of HIV. METHOD: As part of second generation surveillance (SGS), we investigated specific demographic and behavioural characteristics of IDUs in Hyderabad and Sukkur in 2005. It was a cross sectional study. The survey was preceded by geographic mapping to determine size estimation and to define sampling procedures prior to integrated behavioural and biological survey (IBBS). A sample size of at least 400 was calculated for each city. Besides calculating frequencies, chi square was used for comparing variables among HIV positive and negative IDUs like time elapsed as IDU, number of injections, sharing needles and self perception of acquiring HIV infection. RESULTS: A total of 800 (Hyderabad 398; Sukkur 402) questionnaires and DBS samples were collected. The estimated number of IDUs in both cities was 3,225 (Hyderabad 975 and Sukkur 2250 respectively). Average age of IDUs in Hyderabad was 36.5 years and 34.6 years in Sukkur. Sharing of injection equipment for last injection was reported by 34 (8.5%) in Hyderabad and 135 (33.6%) in Sukkur. In both cities behaviours such as injecting drugs for more than 10 years (p = 0.00) and injecting four or more times in a day (p = 0.11) were significantly associated with seropositivity of HIV infection. In Hyderabad the seroprevalence of HIV was 25.4% (101/398) and in Sukkur it was 19.2% (77/402). CONCLUSION: The burden of HIV among IDUs in Hyderabad and Sukkur is extremely high and can play a significant role in transmitting the infection to other vulnerable groups.


Asunto(s)
Infecciones por VIH/epidemiología , Compartición de Agujas/estadística & datos numéricos , Asunción de Riesgos , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto , Factores de Edad , Estudios Transversales , Demografía , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/transmisión , Seroprevalencia de VIH , VIH-1 , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Pakistán/epidemiología , Factores Socioeconómicos , Abuso de Sustancias por Vía Intravenosa/complicaciones , Encuestas y Cuestionarios , Población Urbana
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