Autumn Conditions Research Articles

Impact of crop genetic diversity on a litter consumer

Belowground communities, and especially earthworms, provide numerous services in agroecosystems. In the current context of crop genetic erosion, this study aims at assessing the effect of wheat cultivar diversity on earthworm growth and survival. Our laboratory experiment was divided into two periods: (1) the “feeding period” (4 months), simulating conditions in autumn with cool temperatures and high food availability, and (2) the “non-feeding period” (1 month) simulating conditions in winter with cold temperatures and low food availability because litter had already been consumed without replacement. The aerial biomass of mixtures of wheat cultivars was used as food for earthworms and their growth was measured twice during the feeding period and once during the non-feeding period. We found two major effects on earthworm growth. Increasing the cultivar number (i) increased juvenile earthworm growth and earthworm survival and (ii) decreased adult earthworm growth. A consistent positive effect of nitrogen concentration of the biomass was found on growth and this effect was independent of biodiversity effects. This study suggests that the loss of litter intraspecific genetic diversity has an impact on earthworm populations, probably through mechanisms linked to the variance in edibility or the balanced diet hypotheses. While they remain to be tested in the field, these results suggest that the current losses of crop genetic diversity could potentially impact processes at the community or ecosystem level through a decrease in food quality.

Influence of Green Spaces on Outdoors Thermal Comfort—Structured Experiment in a Mediterranean Climate

As a growing part of the global population lives in cities, green spaces are an essential asset for improving quality of life. This study aims to address the role of green spaces in providing favorable thermal comfort conditions for the use of outdoor spaces. The research methodology consisted of a structured experiment where a defined set of individuals from different age groups was exposed to differentiated microclimate conditions. Four nearby locations were considered, ranging from a stone-paved surface without shade to high tree canopy coverage over grass. This experiment took place in three different days in summer and early autumn conditions, with a total of 432 questionnaires. Results show a wide range of thermal sensations found during this experiment, while more favorable thermal sensations were found in shaded locations. To investigate the role of prevailing meteorological and personal conditions on thermal sensations, multinomial logistic regression analysis was applied. Results show the influence of air temperature, global radiation, wind speed, and interviewees’ gender. As meteorological variables were influenced by the diverse contexts found within a close distance inside the studied green space, results from this structured experiment suggest the need for micrometeorological diversity in the local context as a means to promote greater adaptive opportunities for green spaces users.

The influence of weather conditions during an autumn period on the development of basic wreckers and diseases of agrocenosis of winter wheat in Forest-Steppe zone

Goal. To investigate the influence of weather conditions, to specify the terms of sowing in an autumn period and their influence on the phytosanitary condition of winter wheat’s agrocenosis in the Forest-steppe zone. In conditions of climate change, specify the quantitative composition of the entomological and on phytopathogenic complexes in winter wheat chrops and the peculiarities of their manifestation.
 Methods. Field research, laboratory research, and analytical research. The field researches have been conducted in the conditions of monitoring inspections. The results of the experimental data are counted and collected using modern standard computer programs (Word, Excel).
 Results. Influence of weather conditions was investigated in the autumn period (air temperature, amount of precipitation) for 2006—2016 and the long-term seasonal dynamics of the number of basic wreckers on winter wheat sowing and detected features during climate change. Many years of weather conditions during winter wheat sowing have been analyzed.
 Conclusions. Global warming and drought caused by it in the autumn period prolonged the term of the autumn vegetation of winter wheat. Through droughty conditions, or over wetting optimal terms of sowing were displaced for later. It was researched that optimal terms of winter wheat sowing are considered in the zone of the North Forest-steppe from 15—25 September, which is allowed until 30 September. The increase in air temperature and a sufficient amount of precipitation in the autumn period leads to dissemination of sowing the most widespread wreckers and affection of plants by diseases. With the approach of ETL, there may be a need for protective measures in the conditions of early sowing and prolonged warm autumn, especially after colony precursors. Autumn spraying crops with fungicidal agents prevents plant infections by pathogens in the early phases of plant development.

Production characteristics of Spirulina platensis and Dunaliella salina cultures in the Sevastopol region at the off-season

The calculation of limit productivity for microalgae cultures during cultivation in the autumn period in the southern regions of Russia is carried out. The maximum observed productivity of Spirulina platensis and Dunaliella salina in semi-industrial conditions in autumn (Sevastopol, october-november 2018) was estimated. It is noted that the growth rate is limited by temperature conditions. The possibility of obtaining additional biomass of the studied species during the off-season is shown.

Зимостійкість та перспективи використання рослин-інтродуцентів Rodgersia aesculifolia Batalin в умовах міста Києва

Зимостійкість та перспективи використання рослин-інтродуцентів Rodgersia aesculifolia Batalin в умовах міста Києва

Laboratory acclimation to autumn-like conditions induces freeze tolerance in the spring field cricket Gryllus veletis (Orthoptera: Gryllidae)

Many temperate insects encounter temperatures low enough to freeze their body fluids. Remarkably, some insects are freeze-tolerant, surviving this internal ice formation. However, the mechanisms underlying freeze tolerance are not well-understood, in part due to a lack of tractable model organisms. We describe a novel laboratory model to study insect freeze tolerance, the spring field cricket Gryllus veletis (Orthopera: Gryllidae). Following acclimation to six weeks of decreasing temperature and photoperiod, G. veletis become freeze-tolerant, similar to those exposed to natural autumn conditions in London, Ontario, Canada. Acclimated crickets suppress their metabolic rate by c. 33%, and survive freezing for up to one week at −8 °C, and to temperatures as low as −12 °C. Freeze-tolerant G. veletis protect fat body cells from freeze injury in vivo, and fat body tissue from freeze-tolerant cricket survives brief freeze treatments when frozen ex vivo. Freeze-tolerant crickets freeze at c. −6 °C, which may be initiated by accumulation of ice-nucleating agents in hemolymph or gut tissue. Although we hypothesize that control of ice formation facilitates freeze tolerance, initiating ice formation at high subzero temperatures does not confer freeze tolerance on freeze-intolerant nymphs. Acclimation increases hemolymph osmolality from c. 400 to c. 650 mOsm, which may facilitate freeze tolerance by reducing ice content. Hemolymph ion concentrations do not change with acclimation, and we therefore predict that freeze-tolerant G. veletis elevate hemolymph osmolality by accumulating other molecules. Gryllus veletis is easily reared and manipulated in a controlled laboratory environment, and is therefore a suitable candidate for further investigating the mechanisms underlying freeze tolerance.

Alleviation of morphophysiological dormancy in seeds of the Australian arid-zone endemic shrub, Hibbertia glaberrima F. Muell. (Dilleniaceae)

AbstractMorphophysiological dormancy (MPD) is predominantly found in seeds of temperate regions and is uncommon in arid biomes. MPD has been reported in a number of Hibbertia (Dilleniaceae) species of temperate Australia, and in a single species of the arid zone, H. glaberrima. This study aimed to examine the dormancy and germination ecology of seeds of H. glaberrima. Seeds were subjected to temperature stratification treatments designed to mimic summer and autumn conditions in the Pilbara region of Western Australia. Seed germination and embryo growth were measured. We also tested the interaction between temperature stratification and cycles of drying and wetting designed to mimic sporadic rainfall events. All temperature and moisture treatments were tested in combination (+/–) with the smoke-derived chemical karrikinolide (KAR1). Exposing dormant seeds to temperatures suitable for warm stratification (35°C) for ≥ 8 weeks, followed by incubation at 25°C, resulted in significantly higher germination compared with non-stratified seeds. Exposing seeds to dry/wet cycling in conjunction with temperature stratification did not significantly increase germination. Exposure to KAR1 increased germination under most conditions. Once seeds are shed during October to December, they are exposed to hot and sporadically wet conditions over summer, allowing MPD to be overcome in a proportion of the seed population. Seeds may germinate in autumn (March to April), in conjunction with cooler temperatures. More deeply dormant individuals may require more than one summer to overcome dormancy. Similar to other species occurring in fire-prone ecosystems, fire also plays a crucial role in the germination ecology of H. glaberrima.

Temperature and photoperiod changes affect cucumber sex expression by different epigenetic regulations

BackgroundCucumbers (Cucumis sativus) are known for their plasticity in sex expression. DNA methylation status determines gene activity but is susceptible to environmental condition changes. Thus, DNA methylation-based epigenetic regulation may at least partially account for the instability of cucumber sex expression. Do temperature and photoperiod that are the two most important environmental factors have equal effect on cucumber sex expression by similar epigenetic regulation mechanism? To answer this question, we did a two-factor experiment of temperature and photoperiod and generated methylome and transcriptome data from cucumber shoot apices.ResultsThe seasonal change in the femaleness of a cucumber core germplasm collection was investigated over five consecutive years. As a result, 71.3% of the 359 cucumber accessions significantly decreased their femaleness in early autumn when compared with spring. High temperature and long-day photoperiod treatments, which mimic early autumn conditions, are both unfavorable for female flower formation, and temperature is the predominant factor. High temperatures and long-day treatments both predominantly resulted in hypermethylation compared to demethylation, and temperature effect was decisive. The targeted cytosines shared in high-temperature and long-day photoperiod treatment showed the same change in DNA methylation level. Moreover, differentially expressed TEs (DETs) and the predicted epiregulation sites were clustered across chromosomes, and importantly, these sites were reproducible among different treatments. Essentially, the photoperiod treatment preferentially and significantly influenced flower development processes, while temperature treatment produced stronger responses from phytohormone-pathway-related genes. Cucumber AGAMOUS was likely epicontrolled exclusively by photoperiod while CAULIFLOWER A and CsACO3 were likely epicontrolled by both photoperiod and temperature.ConclusionsSeasonal change of sex expression is a germplasm-wide phenomenon in cucumbers. High temperature and long-day photoperiod might have the same effect on the methylome via the same mechanism of gene-TE interaction but resulted in different epicontrol sites that account for different mechanisms between temperature- and photoperiod-dependent sex expression changes.

Modelling Carbon Fluxes as an Aid to Understanding Perennial Ryegrass (Lolium perenne) Root Dynamics

Despite the importance of roots in determining plant performance, the factors controlling their development and longevity remain poorly understood. Grass morphology is based on repeating units called phytomers, with each capable of producing one leaf, one daughter tiller, and one or more roots. We developed a phytomer-based understanding of root birth, growth and senescence in Lolium perenne, using a modeling approach to explore seasonal effects on root turnover dynamics, and to explore cultivar differences in these processes. Similar to leaves, roots exhibit a clear progression from initiation, growing for approximately seven phyllochrons, with growth rates strongly influenced by environmental conditions. In spring, the phyllochron decreased over the experiment, while it increased in autumn. In spring, C availability exceeding maintenance respiratory requirements allowed root growth at each phytomer position, with a 70/30 split between maintenance and growth. Under C-deficient conditions in autumn, this split was approximately 80/20, with growth limited to younger phytomer positions, while older roots were more susceptible to starvation-induced senescence due to their high C requirements for maintenance respiration.

The discussion on the mystery season of a historical painting “Qing Ming Shang He Tu” by the thermal comfort analysis method

Qing Ming Shang He Tu, also known by its English name as the “Along the River during the Qingming Festival”, is one of the most famous paintings in China to describe the human’s daily life in the capital city Bian Liang (also known as Dong Jing and Kai Feng city today) of Northern Song dynasty. It captures the environment and activities of the city and rural area on both banks of River Bain including architecture, street networks and arrangements, commercial trading activities, characters, transportation, etc. There is a lot of debates about the season described in the painting, most of which is attributed to the spring tomb sweeping festival, to reflect the two words “Qing Ming” in the name of the painting. However other scholars thought some scenes in the painting also show that this is not the scene appearing in the spring, so the season in the painting should be autumn. In addition to the studies in history and in the painting, this study, from a scientific perspective, reproduces the scene model in “Qing Ming Shang He Tu”, through CFD, simulating the environmental conditions of spring and autumn, to discuss the mystery about the season in “Qing Ming Shang He Tu” by thermal comfort analysis method.

Determination of the water gap and the germination ecology of Adenanthera pavonina (Fabaceae, Mimosoideae); the adaptive role of physical dormancy in mimetic seeds.

Dormancy caused by impermeable seed coats, i.e. physical dormancy (PY), regulates the timing of seed germination in species of several genera belonging to 18 angiosperm families. Physical dormancy also occurs in some mimetic species whose seeds mimic brightly coloured, fleshy fruits or arilled seeds. However, the conditions that break dormancy, as well as the location of water gaps in mimetic seeds, remain unclear. Here, we investigated the adaptive role of impermeable coats in the mimetic seeds of Adenanthera pavonina (Fabaceae: Mimosoideae). Specifically, we explored: (i) the conditions that break PY; (ii) the location of the primary water gap that forms during dormancy break; and (iii) the effect of seasonal temperature regimes on seed germination. Seeds were subjected to hot-water treatment, rapid temperature fluctuations and storage at temperatures mimicking summer and autumn conditions. Seed coat anatomy and water-gap regions were characterized using scanning electron microscopy (SEM) and light microscopy. Seeds were artificially buried in the field at 3 and 7 cm depths and exhumed every 6 months for 2 years to monitor germination. Adenanthera pavonina had impermeable seed coats, and thus PY. Seeds treated with hot water and exposed to summer–autumn temperature regimes broke dormancy. Water entered only through the lens (Type-II simple) due to dislodgement of the palisade layer. Seeds buried at 3 cm depth had significantly higher germination than those buried at 7 cm depth, with germination primarily occurring in autumn. Seeds required high summer temperatures followed by moderate autumn temperatures to become permeable to water and germinate in the field during the wet season. We conclude that the impermeable seed coat of A. pavonina is an adaptation that synchronizes germination with the growing season.

Is autumn the key for dengue epidemics in non endemic regions? The case of Argentina.

BackgroundDengue is a major and rapidly increasing public health problem. In Argentina, the southern extreme of its distribution in the Americas, epidemic transmission takes place during the warm season. Since its re-emergence in 1998 two major outbreaks have occurred, the biggest during 2016. To identify the environmental factors that trigger epidemic events, we analyzed the occurrence and magnitude of dengue outbreaks in time and space at different scales in association with climatic, geographic and demographic variables and number of cases in endemic neighboring countries.MethodsInformation on dengue cases was obtained from dengue notifications reported in the National Health Surveillance System. The resulting database was analyzed by Generalized Linear Mixed Models (GLMM) under three methodological approaches to: identify in which years the most important outbreaks occurred in association with environmental variables and propose a risk estimation for future epidemics (temporal approach); characterize which variables explain the occurrence of local outbreaks through time (spatio-temporal approach); and select the environmental drivers of the geographical distribution of dengue positive districts during 2016 (spatial approach).ResultsWithin the temporal approach, the number of dengue cases country-wide between 2009 and 2016 was positively associated with the number of dengue cases in bordering endemic countries and negatively with the days necessary for transmission (DNT) during the previous autumn in the central region of the country. Annual epidemic intensity in the period between 1999–2016 was associated with DNT during previous autumn and winter. Regarding the spatio-temporal approach, dengue cases within a district were also associated with mild conditions in the previous autumn along with the number of dengue cases in neighboring countries. As for the spatial approach, the best model for the occurrence of two or more dengue cases per district included autumn minimum temperature and human population as fixed factors, and the province as a grouping variable. Explanatory power of all models was high, in the range 57–95%.DiscussionGiven the epidemic nature of dengue in Argentina, virus pressure from endemic neighboring countries along with climatic conditions are crucial to explain disease dynamics. In the three methodological approaches, temperature conditions during autumn were best associated with dengue patterns. We propose that mild autumns represent an advantage for mosquito vector populations and that, in temperate regions, this advantage manifests as a larger egg bank from which the adult population will re-emerge in spring. This may constitute a valuable anticipating tool for high transmission risk events.

Formation Mechanisms of the Spring–Autumn Asymmetry of the Midlatitudinal NmF2 under Daytime Quiet Geomagnetic Conditions at Low Solar Activity

Formation mechanism of the spring–autumn asymmetry of the F2-layer peak electron number density of the midlatitudinal ionosphere, NmF2, under daytime quiet geomagnetic conditions at low solar activity are studied. We used the ionospheric parameters measured by the ionosonde and incoherent scatter radar at Millstone Hill on March 3, 2007, March 29, 2007, September 12, 2007, and September 18, 1984. The altitudinal profiles of the electron density and temperature were calculated for the studied conditions using a one-dimensional, nonstationary, ionosphere–plasmasphere theoretical model for middle geomagnetic latitudes. The study has shown that there are two main factors contributing to the formation of the observed spring–autumn asymmetry of NmF2: first, the spring–autumn variations of the plasma drift along the geomagnetic field due to the corresponding variations in the components of the neutral wind velocity, and, second, the difference between the composition of the neutral atmosphere under the spring and autumn conditions at the same values of the universal time and the ionospheric F2-layer peak altitude. The seasonal variations of the rate of O+(4S) ion production, which are associated with chemical reactions with the participation of the electronically excited ions of atomic oxygen, does not significantly affect the studied NmF2 asymmetry. The difference in the degree of influence of O+(4S) ion reactions with vibrationally excited N2 and O2 on NmF2 under spring and autumn conditions does not significantly change the spring–autumn asymmetry of NmF2.

Spatiotemporal modelling of urban quality of life (UQoL) using satellite images and GIS

ABSTRACTIn modern cities, life is primarily formed in interaction with various environmental, social, economic, infrastructural, hygienic, safety, political and cultural conditions. Urban quality of life (UQoL) is the result of such interactions. In general, both objective and subjective approaches are used in the study and modelling of UQoL. So far the studies have been conducted in forms of social and large-scale geographical studies mainly ignoring spatial differences of quality of life (QoL) in complicated urban environments. Moreover, QoL as one of the attributes of geographical environment is a dynamic and variable concept which has received little attention. Spatiotemporal modelling of this concept can contribute to monitoring the UQoL and planning for its improvement. The current study aims to develop a method for spatiotemporal modelling of UQoL. For this purpose, multi criteria decision making (MCDM) method and fuzzy logic are used. Moreover, given the variability of some indicators, temporal modelling of UQoL was conducted based on snapshot method in seasonal scale. In order to evaluate the proposed procedure, modelling of QoL was done at urban blocks scale in regions 3, 6, and 11 of Tehran, Iran. The results show the existence of a fairly regular pattern as an increase in desirability of UQoL from south to north of the area. The seasonal changes of UQoL show the improvement of environmental condition in spring and autumn compared to winter and summer. The result of sensitivity analysis shows the reliability of the modelling results. Since the effect of inputs on the fuzzy gamma output (2.5%) are less than the corresponding amount in VIKOR-fuzzy method (48%), it can be concluded that the output of fuzzy-gamma is more reliable.

Track circuit reliability assessment for preventing railway accidents

The safe operation of a railway signaling system depends on accurate and up-to-date information on the position and movements of trains provided by train detection devices. Track circuits are the most popular systems used over the world to provide information on position and movements of trains and ensure safety of circulations. Track circuits’ failure or malfunction have two consequences: operating unreliability causing train delays, and accidents. In this paper, we focus on potential accidents.In close cooperation with experts and practitioners of the French national railways company SNCF, we have designed a reliability model of track circuits taking into account local conditions: environment, vehicles, track, traffic, track circuit technology and use. Combined with an assessment of potential accidents’ severity due to TC failure, this model aims at supporting managers’ strategies to reduce the risks and optimize resources allocation.This model is also used to predict potential locations of track circuits that may generate malfunctions, using a measure of similarity with track circuits’ locations where malfunctions occurred. Using the database of past malfunctions, the similarity measure uses the model’s parameters to set up and update a classification of malfunction types. Each type is compared with the database of track circuits to identify those that are similar enough to raise attention and check if appropriate prevention measures are already in place or need to be added.The model is used as a support tool by the local staff to optimize the resources needed to ensure safety by setting priorities among track circuits and determining which ones need prevention and/or protection measures.The model was designed and implemented in a French region where track circuits malfunctions have a higher probability to occur due to climatic conditions in autumn that pollute the wheel-rail contact.

Signatures of chlorinated dioxins and furans along the exposure path – The relation between vegetation and soil

Polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDD/Fs) belong to the most toxic persistent organic environmental pollutants. Therefore, knowledge about their fate along the exposure path is of special concern. In order to comprehend the transfer of PCDD/Fs across different environmental compartments, PCDD/F concentrations in plants and in soil were evaluated. Pairs of soil and plant samples were selected according to the shortest distance between sampling points. At 15 sites PCDD/F concentrations in spruce needles and in forest humus layers where compared. Summer conditions were evaluated on the basis of 8 sites with ryegrass- and grassland topsoil samples. Autumn conditions were addressed using 7 sites with curly kale and topsoil samples under grassland. Correlation analyses of the PCDD/F congener profiles for plant- and soil samples were conducted. The correlations were compared to influencing site (e.g. local temperature) and spatial as well as temporal offset parameters. No governing parameter that decisively influenced the similarity between plant and soil signature became evident. By means of the toxicity factors of TEQ-WHO, tetra- and penta-PCDD/F homologues were assigned to the group of low-chlorinated homologues (lcH), and hexa-, hepta- and octa-PCDD/F homologues to the high-chlorinated homologues (hcH). lcH and hcH are presumed to differ in solubility, volatility and rate of degradation. The ratio of lcH/hcH revealed characteristic fingerprints that enabled the differentiation of the individual PCDD/F-plant and -soil pairs. Spruce-humus pairs showed a close relation during winter exposure times, while the lower summer concentrations were not reflected in the humus layer. Kale was exposed at the beginning of the season with elevated PCDD/F immissions, and showed a closer relation to grassland topsoil than did ryegrass. lcH/hcH proved as a simple criterion that can reveal related PCDD/F fingerprints of different environmental compartments despite signal attenuation due to decomposition, volatilization and particulate transport.

Dormancy-breaking and germination requirements of seeds of the Hawaiian endemic Dianella sandwicensis (Xanthorrhoeaceae)

One problem with including some wild plant species in restoration projects is that seeds are dormant and fail to germinate. Thus, information on the dormancy-breaking and germination requirements facilitates propagation of species, such as the Hawaiian endemic Dianella sandwicensis Hook. & Arn., for conservation. In seeds of this species the embryo is shorter than the endosperm, and seeds sown in early summer in Hawai‘i did not germinate until autumn. Thus, we hypothesised that seeds have morphophysiological dormancy (MPD) and that germination is promoted by low (autumn) temperatures. Studies on embryo growth and the temperature requirements for dormancy-break and germination were conducted on seeds of D. sandwicensis collected on three Hawaiian Islands. Prior to germination the embryo length : seed length ratio increased 16.3 to 17.6%; thus, seeds have MPD. Since both embryo growth and germination occurred at 25/15°C, seeds have a simple level of MPD. Seeds germinated to 90–100% at both 20/10 and 25/15°C, but germination was faster at 20/10°C. However, seeds incubated for 12 weeks at 25/15°C then moved to 20/10°C reached 100% germination as rapidly as seeds kept at 20/10°C. Our results show that exposure of seeds to relatively cool autumn (20/10°C) conditions facilitates propagation of this species from seeds.

Favourable and Unfavourable Scenarii of Radiative Fog Formation Defined by Ground-Based and Satellite Observation Data

An innovative set of six observed predictors of fog formation by radiative cooling is proposed, which describes: 1) one of the main processes of fog formation that is the water uptake by aerosols at surface level; 2) the fog development along the vertical up to 30 meters, as well as the cloud cover; and 3) the temporal evolution of the parameters describing the water uptake by aerosols and the cloud cover. The visibility is used as a signal of atmospheric and surface processes affecting the water uptake by aerosols. The vertical fog development is described by the vertical thermal gradient along a 30-m meteorological mast. The cloud cover is described using a ceilometer for low and middle clouds above the instrument, and satellite data for clouds in a pixel and in a larger 9 × 9-pixel region around the site. The set of predictors can be observed in operational conditions, such as on airport fields. Data acquired at the SIRTA platform (Paris, France) during two autumns and two winters were analysed, and the cloud cover classification derived from the SEVIRI instrument on the METEOSAT Second Generation satellite by the EUMETSAT/NWCSAF program was also utilized. The training data set was acquired in November 2011 while the validation data set extended over 12 months. All situations were discriminated between favourable and unfavourable scenarii of radiative cooling fog formation, with a factor of 10 in probability. 246 moderate visibility events (with visibility between 5 and 10 km) were observed under a clear sky in 12 months at SIRTA. While developed fog formed according to one scenario, thin fog formed according to six scenarii. On the contrary to thin fog, developed fog did not form when cirrus clouds were observed above moderate visibility situations. The fog formation probability varied from 12 to 43%, and even reached 100% for one thin fog. As the training data set was acquired in autumn, the predictor set seems more appropriate to nowcast fog in humid autumn conditions, when the fog formation probability was multiplied by ~2. The predictive set could be enriched by predictors proposed in literature, and tests suggest that relative humidity would improve the fog formation probability in winter. Five predictors identify 65 of the 217 no-fog events counted in 12 months, with ~3 h anticipation time. If visibility decreased below 5 km, 88 additional no-fog events were identified. In this case, the formation probability was 35% for developed fog, and 24–60% for thin fog, but with an anticipation time reduced to ~1.5 h. Only one fog, which represents 3% of the fog events, would be missed with such a predictive scheme.

Modelling and analysis of a ground source heat pump combined with a PV-T and earth energy storage system

This paper presents the development of a mathematical model for the analysis of a ground source heat pump unit combined with photovoltaic-thermal panels and an earth energy storage system. Each sub-system was modelled in MATLAB and then merged to form an overall model of the energy system. The model was used to analyse the performance of the energy system using several test scenarios. The test scenarios saw input data for winter, spring, summer and autumn conditions across the periods of 24 hours. The model was used to simulate the system with differing refrigerants, PV/T module sizes and earth energy bank storage sizes. The heat pump shows a Coeffient of Performance of approximately 5.0 throughout the test scenarios. It was observed that the summer conditions produce an increase in the energy stored within the ground, whilst the winter operation shows a reduction due to increased thermal demand in the building and reduced solar irradiance. The model was shown to be simple and effective to capture the operational characteristics of the combined energy system.

Characterisation, analysis of expression and localisation of the opsin gene repertoire from the perspective of photoperiodism in the aphid Acyrthosiphon pisum

Organisms exhibit a wide range of seasonal responses as adaptions to predictable annual changes in their environment. These changes are originally caused by the effect of the Earth’s cycles around the sun and its axial tilt. Examples of seasonal responses include floration, migration, reproduction and diapause. In temperate climate zones, the most robust variable to predict seasons is the length of the day (i.e. the photoperiod). The first step to trigger photoperiodic driven responses involves measuring the duration of the light-dark phases, but the molecular clockwork performing this task is poorly characterized. Photopigments such as opsins are known to participate in light perception, being part of the machinery in charge of providing information about the luminous state of the surroundings. Aphids (Hemiptera: Aphididae) are paradigmatic photoperiodic insects, exhibiting a strong induction to diapause when the light regime mimics autumn conditions. The availability of the pea aphid (Acyrthosiphon pisum) genome has facilitated molecular approaches to understand the effect of light stimulus in the photoperiodic induction process. We have identified, experimentally validated and characterized the expression of the full opsin gene repertoire in the pea aphid. Among identified opsin genes in A. pisum, arthropsin is absent in most insects sequenced to date (except for dragonflies and two other hemipterans) but also present in a crustacean, an onychophoran and chelicerates. We have quantified the expression of these genes in aphids exposed to different photoperiodic conditions and at different times of the day and localized their transcripts in the aphid brain. Clear differences in expression patterns were found, thus relating opsin expression with the photoperiodic response.