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1.
Insects ; 15(5)2024 May 10.
Article in English | MEDLINE | ID: mdl-38786898

ABSTRACT

This study examines the relationship between the wingbeat frequency of flying insects and ambient temperature, leveraging data from over 302,000 insect observations obtained using a near-infrared optical sensor during an eight-month field experiment. By measuring the wingbeat frequency as well as wing and body optical cross-sections of each insect in conjunction with the ambient temperature, we identified five clusters of insects and analyzed how their average wingbeat frequencies evolved over temperatures ranging from 10 °C to 38 °C. Our findings reveal a positive correlation between temperature and wingbeat frequency, with a more pronounced increase observed at higher wingbeat frequencies. Frequencies increased on average by 2.02 Hz/°C at 50 Hz, and up to 9.63 Hz/°C at 525 Hz, and a general model is proposed. This model offers a valuable tool for correcting wingbeat frequencies with temperature, enhancing the accuracy of insect clustering by optical and acoustic sensors. While this approach does not account for species-specific responses to temperature changes, our research provides a general insight, based on all species present during the field experiment, into the intricate dynamics of insect flight behavior in relation to environmental factors.

2.
Sci Rep ; 13(1): 15606, 2023 09 20.
Article in English | MEDLINE | ID: mdl-37731042

ABSTRACT

Monitoring the dynamics of insect populations is key to assessing the impact of human activities on insect populations. However, traditional methodologies relying on physical traps have inherent limitations in accurately monitoring insect abundance. Here, we present findings from a 9-month campaign conducted in New Jersey, USA, utilizing a near-infrared optical sensor known as eBoss. From April to December 2022, the eBoss derived the aerial density (insect/m3) and biomass density (mg/m3) with a 1-min resolution from a total of 302,093 insect observations. The data collected were analyzed in relation to air temperature, relative humidity, and wind speed. The results revealed that the abundance of flying insects exhibited an initial increase from April to June, reaching a peak of 0.094 insect/m3 and 1.34 mg/m3, followed by a subsequent decline towards the end of the year. Our investigation showed a surge in insect abundance above 12.5 °C, with particularly high levels observed between 19 and 31 °C. The impact of relative humidity and wind speed on insect populations was also explored. Overall, this campaign demonstrated the efficacy of photonic sensors in gathering novel and extensive data for the field of entomology, paving the way for improved understanding and management of insect populations.


Subject(s)
Climate , Wind , Humans , Animals , Temperature , Biomass , Insecta
3.
Appl Phys B ; 129(2): 26, 2023.
Article in English | MEDLINE | ID: mdl-36685802

ABSTRACT

Insects are major actors in Earth's ecosystems and their recent decline in abundance and diversity is alarming. The monitoring of insects is paramount to understand the cause of this decline and guide conservation policies. In this contribution, an infrared laser-based system is used to remotely monitor the biomass density of flying insects in the wild. By measuring the optical extinction caused by insects crossing the 36-m long laser beam, the Entomological Bistatic Optical Sensor System used in this study can evaluate the mass of each specimen. At the field location, between July and December 2021, the instrument made a total of 262,870 observations of insects for which the average dry mass was 17.1 mg and the median 3.4 mg. The daily average mass of flying insects per meter cube of air at the field location has been retrieved throughout the season and ranged between near 0 to 1.2 mg/m3. Thanks to its temporal resolution in the minute range, daily variations of biomass density have been observed as well. These measurements show daily activity patterns changing with the season, as large increases in biomass density were evident around sunset and sunrise during Summer but not during Fall.

4.
PLoS One ; 16(11): e0260167, 2021.
Article in English | MEDLINE | ID: mdl-34793570

ABSTRACT

Although small in size, insects are a quintessential part of terrestrial ecosystems due to their large number and diversity. While captured insects can be thoroughly studied in laboratory conditions, their population dynamics and abundance in the wild remain largely unknown due to the lack of accurate methodologies to count them. Here, we present the results of a field experiment where the activity of insects has been monitored continuously over 3 months using an entomological stand-off optical sensor (ESOS). Because its near-infrared laser is imperceptible to insects, the instrument provides an unbiased and absolute measurement of the aerial density (flying insect/m3) with a temporal resolution down to the minute. Multiple clusters of insects are differentiated based on their wingbeat frequency and ratios between wing and body optical cross-sections. The collected data allowed for the study of the circadian rhythm and daily activities as well as the aerial density dynamic over the whole campaign for each cluster individually. These measurements have been compared with traps for validation of this new methodology. We believe that this new type of data can unlock many of the current limitations in the collection of entomological data, especially when studying the population dynamics of insects with large impacts on our society, such as pollinators or vectors of infectious diseases.


Subject(s)
Circadian Rhythm/physiology , Insecta/physiology , Wings, Animal/physiology , Animals , Ecosystem , Pollination/physiology , Population Dynamics
5.
J Phys Chem B ; 125(44): 12384-12391, 2021 Nov 11.
Article in English | MEDLINE | ID: mdl-34705447

ABSTRACT

Unlike counterion interactions with charged interfaces, the influence of co-ions is only scarcely reported in the literature. In this work, the effect of SCN- and the halide co-ions in the interactions of Na+ with carboxylic acid Langmuir monolayers is investigated by using vibrational sum frequency spectroscopy. At 1 M concentrations in the subphase, the identity of the anion is shown to have a remarkable influence on the charging behavior and degree of deprotonation of the monolayer, with ions ordering in the sequence I- > SCN- > Cl- ≈ Br-. The same trend is observed at both pH 6 and pH 9 when the monolayer is intrinsically more charged. Spectroscopic evidence is found for both the presence of I- and SCN- in the interfacial region at levels close to their detection limits. The results contradict electrostatic theories on charged interfaces where co-ions are not expected to play any significant role. The higher propensity for the large polarizable anions to deprotonate the monolayer is explained in terms of their ability to modify the cations affinity toward the carboxylic acid groups present at the surface.

6.
Viruses ; 13(5)2021 05 04.
Article in English | MEDLINE | ID: mdl-34064404

ABSTRACT

The HIV replication cycle depends on the interaction of viral proteins with proteins of the host. Unraveling host-pathogen interactions during the infection is of great importance for understanding the pathogenesis and the development of antiviral therapies. To date HIV uncoating and nuclear import are the most debated steps of the HIV-1 replication cycle. Despite numerous studies during past decades, there is still much controversy with respect to the identity and the role of viral and host factors involved in these processes. In this review, we provide a comprehensive overview on the role of transportin-SR2 as a host cell factor during active nuclear transport.


Subject(s)
HIV Infections/metabolism , HIV Infections/virology , HIV-1/physiology , Host-Pathogen Interactions , Virus Replication , beta Karyopherins/metabolism , Active Transport, Cell Nucleus/drug effects , Capsid/metabolism , Cyclophilin A/pharmacology , HIV Integrase/metabolism , Humans , Models, Biological , Protein Binding , mRNA Cleavage and Polyadenylation Factors/metabolism
7.
J Biophotonics ; 12(10): e201900123, 2019 10.
Article in English | MEDLINE | ID: mdl-31211902

ABSTRACT

Improving the survey of mosquito populations is of the utmost importance to further enhance mitigation techniques that protect human populations from mosquito-borne diseases. While mosquito populations are generally studied using physical traps, stand-off optical sensors allow to study insect ecosystems with potentially better spatial and temporal resolution. This can be greatly beneficial to eco-epidemiological models and various mosquito control programs. In this contribution, we demonstrate that the gravidity of female mosquitoes can be identified from changes in their spectral and polarimetric backscatter cross sections. Among other predictive variables, the wing beat frequency and the depolarization ratio of the mosquito body allows for the identification of gravid females with a precision and recall of 86% and 87%, respectively. Since female mosquitoes need a blood meal to become gravid, statistics on gravidity is of prime importance as only females that have been gravid might carry infectious diseases. In addition, it allows to detect possible breeding habitat, predict a potential increase in the mosquito population and provide a better overall understanding of the ecosystem dynamics. As a result, targeted and localized mitigation techniques can be used, reducing the cost and improving the efficiency of mosquito population control.


Subject(s)
Culicidae/physiology , Gravidity , Optical Phenomena , Animals , Discriminant Analysis , Environmental Monitoring , Female , Machine Learning , Pregnancy , Spectrum Analysis
8.
Appl Phys B ; 124(3)2018 Mar.
Article in English | MEDLINE | ID: mdl-30505073

ABSTRACT

Mosquito-borne diseases are a major challenge for Human health as they affect nearly 700 million people every year and result in over 1 million deaths. Reliable information on the evolution of population and spatial distribution of key insects species is of major importance in the development of eco-epidemiologic models. This paper reports on the remote characterization of flying mosquitoes using a continuous-wave infrared optical remote sensing system. The system is setup in a controlled environment to mimic long-range lidars, mosquitoes are free flying at a distance of ~ 4 m from the collecting optics. The wing beat frequency is retrieved from the backscattered light from mosquitoes transiting through the laser beam. A total of 427 transit signals have been recorded from three mosquito species, males and females. Since the mosquito species and gender are known a priori, we investigate the use of wing beat frequency as the sole predictor variable for two Bayesian classifications: gender alone (two classes) and species/gender (six classes). The gender of each mosquito is retrieved with a 96.5% accuracy while the species/gender of mosquitoes is retrieved with a 62.3% accuracy. Known to be an efficient mean to identify insect family, we discuss the limitations of using wing beat frequency alone to identify insect species.

9.
Article in English | MEDLINE | ID: mdl-31656364

ABSTRACT

Mosquito-borne diseases are a major challenge for Human health as they affect nearly 700 million people every year. Monitoring insects is generally done through trapping methods that are tedious to set up, costly and present scientific biases. Entomological lidars are a potential solution to remotely count and identify mosquito species and gender in real-time. In this contribution, a dual-wavelength polarization sensitive lidar is used in laboratory conditions to retrieve the wingbeat frequency as well as optical properties of flying mosquitoes transiting through the laser beam. From the lidar signals, predictive variables are retrieved and used in a Bayesian classification. This paper focuses on determining the relative importance of the predictive variables used in the classification. Results show a strong dominance of the wingbeat frequency, the impact of predictive variables based on depolarization and backscattering ratios are discussed, showing a significant increase in classification accuracy.

10.
Bull Soc Pathol Exot ; 111(1): 17-23, 2018.
Article in French | MEDLINE | ID: mdl-30763500

ABSTRACT

Haiti, like most limited-resources countries in the world, faces numerous neglected infectious diseases. They represent a real public health issue with lethal consequences especially in children. We are reviewing here the available literature on four neglected infectious diseases, mansonelliasis, tungiasis, leprosy and anthrax. Filariasis, due to Mansonella ozzardi, has been totally neglected since its discovery in 1920 in Haiti; it persists in coastal homes with a high prevalence in adults when an effective treatment is available. The skin lesions caused by Tunga penetrans have existed since the pre-Columbian period in Haiti. They persist in the most retreated and hard-to-reach areas where the population lives in precarious conditions and in extreme poverty. New available research data show the importance of the problem with very high prevalence rates in some rural communities far away from any healthcare center. Cases of leprosy are recently reemerging as no monitoring program has been in place since 2004. Finally, anthrax is still endemic; small epidemics resurfacing periodically in families in rural areas. Screening of people for these diseases and managing the cases are necessary to improve health and reduce morbidity and mortality in Haiti.


Comme dans la plupart des pays pauvres de la planète, les maladies infectieuses négligées sont nombreuses en Haïti où elles représentent un réel problème de santé publique avec des conséquences létales, surtout pour les enfants. Nous faisons le point des données accessibles pour quatre d'entre elles. Totalement délaissée depuis la découverte de sa présence en Haïti en 1920, la filariose due à Mansonella ozzardi persiste en foyers côtiers avec une prévalence élevée chez les adultes alors qu'un traitement efficace est disponible. Connues depuis la période précolombienne dans l'île d'Hispaniola, les lésions cutanées dues à Tunga penetrans persistent dans les régions les plus reculées et difficiles d'accès où la population vit dans des conditions précaires et dans une très grande pauvreté. Nous rapportons les données d'enquêtes récentes qui montrent l'importance de cette ectoparasitose en Haïti où les taux de prévalence sont très élevés dans certaines communautés rurales isolées. Des cas de lèpre resurgissent en Haïti alors qu'aucun programme de surveillance n'est effectif depuis 2004. Enfin, la maladie du charbon est endémique dans les régions d'élevage où des épidémies familiales resurgissent périodiquement en milieu rural. Le dépistage des personnes atteintes de ces maladies et leur prise en charge sont nécessaires pour une amélioration de la santé et une baisse de la mortalité en Haïti.


Subject(s)
Anthrax/epidemiology , Leprosy/epidemiology , Mansonelliasis/epidemiology , Neglected Diseases/epidemiology , Tungiasis/epidemiology , Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Filariasis/epidemiology , Haiti/epidemiology , Humans , Infant , Infant, Newborn , Male , Middle Aged , Prevalence , Young Adult
11.
J Am Chem Soc ; 130(36): 11872-3, 2008 Sep 10.
Article in English | MEDLINE | ID: mdl-18707184

ABSTRACT

This paper reports the synthesis and characterization of a new crystalline 3D covalent organic framework, COF-202: [C(C6H4)4]3[B3O6 (tBuSi)2]4, formed from condensation of a divergent boronic acid, tetra(4-dihydroxyborylphenyl)methane, and tert-butylsilane triol, tBuSi(OH)3. This framework is constructed through strong covalent bonds (Si-O, B-O) that link triangular and tetrahedral building units to form a structure based on the carbon nitride topology. COF-202 demonstrates high thermal stability, low density, and high porosity with a surface area of 2690 m2 g-1. The design and synthesis of COF-202 expand the type of linkage that could be used to crystallize new materials with extended covalent organic frameworks.

12.
Nature ; 453(7192): 207-11, 2008 May 08.
Article in English | MEDLINE | ID: mdl-18464739

ABSTRACT

Zeolitic imidazolate frameworks (ZIFs) are porous crystalline materials with tetrahedral networks that resemble those of zeolites: transition metals (Zn, Co) replace tetrahedrally coordinated atoms (for example, Si), and imidazolate links replace oxygen bridges. A striking feature of these materials is that the structure adopted by a given ZIF is determined by link-link interactions, rather than by the structure directing agents used in zeolite synthesis. As a result, systematic variations of linker substituents have yielded many different ZIFs that exhibit known or predicted zeolite topologies. The materials are chemically and thermally stable, yet have the long-sought-after design flexibility offered by functionalized organic links and a high density of transition metal ions. Here we report the synthesis and characterization of two porous ZIFs-ZIF-95 and ZIF-100-with structures of a scale and complexity previously unknown in zeolites. The materials have complex cages that contain up to 264 vertices, and are constructed from as many as 7,524 atoms. As expected from the adsorption selectivity recently documented for other members of this materials family, both ZIFs selectively capture carbon dioxide from several different gas mixtures at room temperature, with ZIF-100 capable of storing 28 litres per litre of material at standard temperature and pressure. These characteristics, combined with their high thermal and chemical stability and ease of fabrication, make ZIFs promising candidate materials for strategies aimed at ameliorating increasing atmospheric carbon dioxide levels.

14.
Nat Mater ; 6(7): 501-6, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17529969

ABSTRACT

Faujasite (FAU) and zeolite A (LTA) are technologically important porous zeolites (aluminosilicates) because of their extensive use in petroleum cracking and water softening. Introducing organic units and transition metals into the backbone of these types of zeolite allows us to expand their pore structures, enhance their functionality and access new applications. The invention of metal-organic frameworks and zeolitic imidazolate frameworks (ZIFs) has provided materials based on simple zeolite structures where only one type of cage is present. However, so far, no metal-organic analogues based on FAU or LTA topologies exist owing to the difficulty imposed by the presence of two types of large cage (super- and beta-cages for FAU, alpha- and beta-cages for LTA). Here, we have identified a strategy to produce an LTA imidazolate framework in which both the link geometry and link-link interactions play a decisive structure-directing role. We describe the synthesis and crystal structures of three porous ZIFs that are expanded analogues of zeolite A; their cage walls are functionalized, and their metal ions can be changed without changing the underlying LTA topology. Hydrogen, methane, carbon dioxide and argon gas adsorption isotherms are reported and the selectivity of this material for carbon dioxide over methane is demonstrated.

15.
Science ; 316(5822): 268-72, 2007 Apr 13.
Article in English | MEDLINE | ID: mdl-17431178

ABSTRACT

Three-dimensional covalent organic frameworks (3D COFs) were synthesized by targeting two nets based on triangular and tetrahedral nodes: ctn and bor. The respective 3D COFs were synthesized as crystalline solids by condensation reactions of tetrahedral tetra(4-dihydroxyborylphenyl) methane or tetra(4-dihydroxyborylphenyl)silane and by co-condensation of triangular 2,3,6,7,10,11-hexahydroxytriphenylene. Because these materials are entirely constructed from strong covalent bonds (C-C, C-O, C-B, and B-O), they have high thermal stabilities (400 degrees to 500 degrees C), and they also have high surface areas (3472 and 4210 square meters per gram for COF-102 and COF-103, respectively) and extremely low densities (0.17 grams per cubic centimeter).

16.
Proc Natl Acad Sci U S A ; 103(27): 10186-10191, 2006 Jul 05.
Article in English | MEDLINE | ID: mdl-16798880

ABSTRACT

Twelve zeolitic imidazolate frameworks (ZIFs; termed ZIF-1 to -12) have been synthesized as crystals by copolymerization of either Zn(II) (ZIF-1 to -4, -6 to -8, and -10 to -11) or Co(II) (ZIF-9 and -12) with imidazolate-type links. The ZIF crystal structures are based on the nets of seven distinct aluminosilicate zeolites: tetrahedral Si(Al) and the bridging O are replaced with transition metal ion and imidazolate link, respectively. In addition, one example of mixed-coordination imidazolate of Zn(II) and In(III) (ZIF-5) based on the garnet net is reported. Study of the gas adsorption and thermal and chemical stability of two prototypical members, ZIF-8 and -11, demonstrated their permanent porosity (Langmuir surface area = 1,810 m(2)/g), high thermal stability (up to 550 degrees C), and remarkable chemical resistance to boiling alkaline water and organic solvents.


Subject(s)
Imidazoles/chemistry , Temperature , Zeolites/chemistry , Crystallography, X-Ray , Molecular Structure
18.
Science ; 310(5751): 1166-70, 2005 Nov 18.
Article in English | MEDLINE | ID: mdl-16293756

ABSTRACT

Covalent organic frameworks (COFs) have been designed and successfully synthesized by condensation reactions of phenyl diboronic acid {C6H4[B(OH)2]2} and hexahydroxytriphenylene [C18H6(OH)6]. Powder x-ray diffraction studies of the highly crystalline products (C3H2BO)6.(C9H12)1 (COF-1) and C9H4BO2 (COF-5) revealed expanded porous graphitic layers that are either staggered (COF-1, P6(3)/mmc) or eclipsed (COF-5, P6/mmm). Their crystal structures are entirely held by strong bonds between B, C, and O atoms to form rigid porous architectures with pore sizes ranging from 7 to 27 angstroms. COF-1 and COF-5 exhibit high thermal stability (to temperatures up to 500 degrees to 600 degrees C), permanent porosity, and high surface areas (711 and 1590 square meters per gram, respectively).

19.
J Am Chem Soc ; 127(30): 10502-3, 2005 Aug 03.
Article in English | MEDLINE | ID: mdl-16045333

ABSTRACT

To combine the stability of alpha-oligothiophenes with the planarity of acenes, fully fused oligothienoacenes were synthesized and their properties compared to the nonfused alpha-oligothiophenes. By employing removable solubilizing groups, our synthetic methodology made it possible to efficiently prepare and purify oligothienoacenes with up to seven fused rings. The key steps involved the halogen dance reaction and Pd-catalyzed coupling of Bu3SnSSnBu3 to introduce sulfur linkages. This approach eliminates alpha-beta anion equilibration, a significant improvement over the traditional method of introducing sulfur linkages via Li-Br exchange. X-ray diffraction data indicate that pentathienoacene and heptathienoacene adopt pi-stacked packing motifs in contrast to the herringbone packing of nonfused oligothiophenes. On the basis of the linear dependence of the longest lambdamax on the reciprocal number of double bonds of thienoacenes with three to seven rings, the band gap of polythienoacene is extrapolated to be 2.21 eV.

20.
J Am Chem Soc ; 127(19): 7110-8, 2005 May 18.
Article in English | MEDLINE | ID: mdl-15884953

ABSTRACT

A strategy based on assembling metal ions and organic carboxylate links has been applied for the design and synthesis of a new class of porous, truncated tetrahedral and heterocuboidal polyhedra, whose pore size and functionality can be systematically varied. The synthesis of this series of metal-organic polyhedra (MOPs) employs sulfate-capped oxygen-centered iron-carboxylate trimers, Fe3O(CO2)3(-)(SO4)3, as rigid nodes separated by linear (phenyl, biphenyl, terphenyl, and tetrahydropyrene) or trigonal (benzenetriphenyl) links to yield five highly crystalline polyhedra of general formula [NH2(CH3)2]8[Fe12O4(-)(SO4)12(link)x(py)12].G (x = 6 for linear or 4 for trigonal, py = pyridine, G = guests). In this series, the size of each polyhedron has been varied from 20.0 to 28.5 A (on edge), and the corresponding pore diameter from 7.3 to 13.3 A. Gas sorption isotherms were measured for three members of this series to reveal significant uptake of gases (N2, Ar, CO2, H2, CH4) and benzene and exhibit Type I sorption behavior that is indicative of permanent porosity. The apparent surface areas for these compounds range from 387 to 480 m(2)/g.

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