511Microphytobenthos (MPB), consisting of benthic phototrophs such as microalgae, cyanobacteria, and dinoflagellates, is the fundament of the trophic food web in coastal ecosystems. In shallow-water environments, such as intertidal flats and estuaries, MPB represents a considerable portion of the autotrophic biomass, accounting for up to 50% of the primary production Nozais et al. 2001;Spilmont et al. 2006). MPB is the predominant food source for many deposit-feeding organisms, and the activity and distribution of MPB profoundly affect nutrient fluxes across the sediment-water interface, sediment geochemistry, as well as sediment morphology and stability (Sundbäck et al. 1991;Montagna et al. 1995;Miller et al. 1996;Stal 2010).The spatio-temporal organization of a community is a prominent issue in ecology. Levin (1992) argued that analysis of large-scale (regional) patterns must integrate effects occurring at smaller scales. Generally, the distribution of MPB is affected by both abiotic processes (e.g., nutrient availability, hydrodynamic exposure, sediment type) and biotic processes (e.g., grazing, competition) through a complex network of interactions. In their reductionist approach to benthic ecology, Miller et al. (1996) argued that studies of interactions with a direct effect on the MPB distribution (so called "isolated first-order interactions") are required to disentangle the complex relationships between the sediment bed, infaunal organisms, and the water column, and for a comprehensive picture AbstractWe describe a novel, field-deployable hyperspectral imaging system, called Hypersub, that allows noninvasive in situ mapping of the microphytobenthos (MPB) biomass distribution with a high spatial (sub-millimeter) and temporal (minutes) resolution over areas of 1 × 1 m. The biomass is derived from a log-transformed and near-infrared corrected reflectance hyperspectral index, which exhibits a linear relationship (R 2 > 0.97) with the chlorophyll a (Chl a) concentration in the euphotic zone of the sediment and depends on the sediment grain size. Deployments of the system revealed that due to factors such as sediment topography, bioturbation, and grazing, the distribution of MPB in intertidal sediments is remarkably heterogeneous, with Chl a concentrations varying laterally by up to 400% of the average value over a distance of 1 cm. Furthermore, due to tidal cycling and diel light variability, MPB concentrations in the top 1 mm of sediments are very dynamic, changing by 40-80% over a few hours due to vertical migration. We argue that the high-resolution hyperspectral imaging method overcomes the inadequate resolution of traditional methods based on sedimentary Chl a extraction, and thus helps improve our understanding of the processes that control benthic primary production in coastal sediments.

Here we present, to the best of our knowledge, the first balanced light energy budget for a benthic microbial mat ecosystem, and show how the budget and the spatial distribution of the local photosynthetic efficiencies within the euphotic zone depend on the absorbed irradiance (J abs ). Our approach uses microscale measurements of the rates of heat dissipation, gross photosynthesis and light absorption in the system, and a model describing light propagation and conversion in a scattering-absorbing medium. The energy budget was dominated by heat dissipation on the expense of photosynthesis: in light-limiting conditions, 95.5% of the absorbed light energy dissipated as heat and 4.5% was channeled into photosynthesis. This energy disproportionation changed in favor of heat dissipation at increasing irradiance, with 499% of the absorbed light energy being dissipated as heat and o1% used by photosynthesis at J abs 4700 lmol photon m À2 s À1 (4150 J m À2 s À1). Maximum photosynthetic efficiencies varied with depth in the euphotic zone between 0.014À0.047 O 2 per photon. Owing to steep light gradients, photosynthetic efficiencies varied differently with increasing irradiances at different depths in the euphotic zone; for example, at J abs 4700 lmol photon m À2 s À1 , they reached around 10% of the maximum values at depths 0À0.3 mm and progressively increased toward 100% below 0.3 mm. This study provides the base for addressing, in much more detail, the photobiology of densely populated photosynthetic systems with intense absorption and scattering. Furthermore, our analysis has promising applications in other areas of photosynthesis research, such as plant biology and biotechnology.

Here we describe a spectral imaging system for minimally invasive identification, localization, and relative quantification of pigments in cells and microbial communities. The modularity of the system allows pigment detection on spatial scales ranging from the single-cell level to regions whose areas are several tens of square centimeters. For pigment identification in vivo absorption and/or autofluorescence spectra are used as the analytical signals. Along with the hardware, which is easy to transport and simple to assemble and allows rapid measurement, we describe newly developed software that allows highly sensitive and pigment-specific analyses of the hyperspectral data. We also propose and describe a number of applications of the system for microbial ecology, including identification of pigments in living cells and high-spatial-resolution imaging of pigments and the associated phototrophic groups in complex microbial communities, such as photosynthetic endolithic biofilms, microbial mats, and intertidal sediments. This system provides new possibilities for studying the role of spatial organization of microorganisms in the ecological functioning of complex benthic microbial communities or for noninvasively monitoring changes in the spatial organization and/or composition of a microbial community in response to changing environmental factors.Spectral imaging is a technique in which spectral information (i.e., the spectrum of light that is scattered from, transmitted through, or emitted by an object) is acquired at every location in an image. Since the spectral information reflects the object's identity, status, and/or composition, combining it with spatial information (i.e., the size, shape, and location of the object) enhances our ability to unravel and understand possible links between the spatial organization and functional relationships for constituents of a system. These attributes have made spectral imaging important in various areas of basic research and in industrial applications.Generally, previously described methods concentrated either on very large scales (e.g., astronomy and satellite or airborne remote sensing of the Earth) or on very small scales (e.g., microscopic observations in medicine and microbiology). In the field of benthic microbial ecology, which is the focus of this paper, large-scale spectral imaging techniques generally aim to identify pigments or to quantify biomass concentrations in microbial communities spread over several meters to kilometers, such as intertidal flats (5,6,17,20). Such techniques usually employ airborne imagers to detect reflected light in several tens of spectral bands covering visible and near-infrared regions. The spectral reflectance data are calibrated and validated by combining ground truth measurements of the parameters of interest (e.g., pigment content) with the spectral reflectance measurements obtained using single-point spectrometers, which detect the signals from regions whose areas are several square centimeters to several square decimeters. Quali...

Purpose COVID-19 infection is normally followed by several post-COVID effects. This study aimed to investigate to evaluate menstrual changes in females following COVID-19 infection, and to evaluate female perception about the effect of COVID-19 on their menstrual cycles. Methods During this cross-sectional survey-based study, a convenience sample of 483 women from Jordan and from Iraq, who had infected with COVID-19 were invited to fill-out the study questionnaire. Results The study was conducted on the females, with a median age 31 years old. Results showed that 47.2% of them (n = 228) suffered from a change in the number of days between two consecutive periods, as well as from a change in the amount of blood loss. Also, more than 50% of them believed that COVID-19 infection may cause changes in the amount of blood loss during the cycle (n = 375, 56.9%), and changes in the number of days between the two consecutive periods (n = 362, 54.2%). Regression analysis showed that participants with higher educational level (bachelor or higher) (Beta = -0.114, P = 0.011), and those living in Iraq (Beta = -0.166, P<0.001) believed that COVID-19 has lower tendency to cause menstrual changes. In addition, non-married females (Beta = 0.109, P = 0.017), and those who are current smokers (Beta = 0.091, P = 0.048) believed that COVID-19 has higher tendency to cause menstrual changes. Conclusion his study revealed that COVID-19 infection could affect the menstrual cycle for the females. Further prospective studies should be done to confirm these findings and evaluate how long these menstrual irregularities lasted.

The Um Alhool area in Qatar is a dynamic evaporative ecosystem that receives seawater from below as it is surrounded by sand dunes. We investigated the chemical composition, the microbial activity and biodiversity of the four main layers (L1–L4) in the photosynthetic mats. Chlorophyll a (Chl a) concentration and distribution (measured by HPLC and hyperspectral imaging, respectively), the phycocyanin distribution (scanned with hyperspectral imaging), oxygenic photosynthesis (determined by microsensor), and the abundance of photosynthetic microorganisms (from 16S and 18S rRNA sequencing) decreased with depth in the euphotic layer (L1). Incident irradiance exponentially attenuated in the same zone reaching 1% at 1.7-mm depth. Proteobacteria dominated all layers of the mat (24%–42% of the identified bacteria). Anoxygenic photosynthetic bacteria (dominated by Chloroflexus) were most abundant in the third red layer of the mat (L3), evidenced by the spectral signature of Bacteriochlorophyll as well as by sequencing. The deep, black layer (L4) was dominated by sulfate reducing bacteria belonging to the Deltaproteobacteria, which were responsible for high sulfate reduction rates (measured using 35S tracer). Members of Halobacteria were the dominant Archaea in all layers of the mat (92%–97%), whereas Nematodes were the main Eukaryotes (up to 87%). Primary productivity rates of Um Alhool mat were similar to those of other hypersaline microbial mats. However, sulfate reduction rates were relatively low, indicating that oxygenic respiration contributes more to organic material degradation than sulfate reduction, because of bioturbation. Although Um Alhool hypersaline mat is a nutrient-limited ecosystem, it is interestingly dynamic and phylogenetically highly diverse. All its components work in a highly efficient and synchronized way to compensate for the lack of nutrient supply provided during regular inundation periods.