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The use of Compton cameras for medical imaging and its interest as a hadron therapy treatment monitoring has increased in the last decade with the development of silicon photomultipliers. MACACO is a Compton camera prototype designed and assembled at the IRIS group of IFIC-Valencia. This Compton camera is based on monolithic Lanthanum (III) Bromide crystals and silicon photomultipliers, and employs the novel TOFPET2 ASIC as readout electronics. This system emerged as an alternative to MACACO II prototype, with the aim of improving its limited time resolution. To test the performance of the ASIC in a Compton camera setup, the prototype was characterized, both in laboratory and in-beam. A time resolution of 1.5 ns was obtained after time corrections, which improves greatly the performance of the MACACO II. Moreover, the results obtained at high photon energies demonstrate the ability of the system to obtain 1 mm displacements of the reconstructed spots. The results reinforce the potential of the system as a monitoring device for hadron therapy., This work has received funding from the Generalitat Valenciana, Spain (AICO/2019070) and from the Spanish Ministerio de Ciencia e Innovación (PID2019-110657RB-100). Group members are supported by UVEG Atracció de Talent, FPU, CDEIGENT, SEJIGENT and Generalitat Valenciana contracts. M.C. Jiménez-Ramos acknowledges the support to this work through a VI PPIT-US contract.

Objective. To demonstrate the benefits of using an joint image reconstruction algorithm based on the List Mode Maximum Likelihood Expectation Maximization that combines events measured in different channels of information of a Compton camera. Approach. Both simulations and experimental data are employed to show the algorithm performance. Main results. The obtained joint images present improved image quality and yield better estimates of displacements of high-energy gamma-ray emitting sources. The algorithm also provides images that are more stable than any individual channel against the noisy convergence that characterizes Maximum Likelihood based algorithms. Significance. The joint reconstruction algorithm can improve the quality and robustness of Compton camera images. It also has high versatility, as it can be easily adapted to any Compton camera geometry. It is thus expected to represent an important step in the optimization of Compton camera imaging.

This work presents the design and method of measuring the impedance in a fluidic unit containing a metal solution using a concave capacitive sensor. The prototype of the design is tested with metal solutions over a range of frequency onto a specific concentration. The system is also tested to get the optimal operating frequency of the sensor at different set of frequencies. A graphical model of each sample’s capacitance versus frequency is determined to fit to a mathematical function that describes the frequency dependence of the fluidic unit. The performance of the whole system is demonstrated in an exemplary measurement.

International audience; The IRIS group at IFIC-Valencia has developed a second version of a Compton camera prototype for hadron therapy treatment monitoring, with the aim of improving the performance with respect to its predecessor. The system is composed of three Lanthanum (III) bromide (LaBr 3) crystals coupled to silicon photomultipliers (SiPMs). The detector energy resolution has been improved to 5.6 % FWHM at 511 keV and an angular resolution of 8.0 • has been obtained. Images of a 22 Na point-like source have been reconstructed selecting two and three interaction events. Moreover, the experimental data have been reproduced with Monte Carlo simulations using a Compton camera module (CCMod) in GATE v8.2 obtaining a good correlation.

Systemic lupus erythematosus (SLE) involves a broad range of factors that contribute to the development of the disease and its comorbidities. Genetic predisposition influences the development of SLE, and the -675 4G/5G

The presence of aflatoxin B1 in livestock's feed results in contamination of milk and its products with aflatoxin M1. Different sequestering agents have been added to cows' ration to adsorb these toxins, although influence of processed bentonites on aflatoxins adsorption has not been evaluated yet. This experiment was carried out to assess the effects of incorporating natural and processed bentonite (local or commercially available), to the diet of Holstein dairy cows subjected to an aflatoxin B1 diet, and the transfer of aflatoxin metabolites (AFM1) to milk. Aflatoxin sequestering capacity, pH, CEC, XRD and XRF of natural and processed bentonites were measured. Then, twelve Holstein dairy cows were assigned to 3 treatments as the following: 1) local processed bentonite (G.Bind™), 2) local unprocessed bentonite (F), and 3) commercially available bentonite (M). Aflatoxin content in feed and milk was evaluated and transfer rate was measured. Results of the present study showed that the aflatoxin contents of milk were remained unchanged except for treatment G.Bind™ that considerably decreased aflatoxin M1 in milk after the second and third weeks of the experiment. G.Bind™ lowered the transfer rate of aflatoxin B1 from 1.17% at the beginning of the experiment to 0.43% and 0.39% after the first and second weeks, respectively. Processing of bentonites (basic processing in present study) can considerably help to adsorb aflatoxin from feed and also to decrease aflatoxin transfer to milk.

In recent decades, PET scanners have been widely used for diagnosis and treatment monitoring in nuclear medicine. The continuous effort of the scientific community has led to improvements in scanner performance. Total-body PET is one of the latest upgrades in PET scanners. These kinds of scanners are able to scan the whole body of the patient with a single bed position, since the scanner tube is long enough for the patient to fit inside. While these scanners show unprecedented efficiency and extended field-of-view, a drawback is their low spatial resolution compared to dedicated scanners. In order to improve the spatial resolution of specific areas when measuring with a total-body PET scanner, the IRIS group at IFIC-Valencia is developing a probe. The proposed setup of the probe contains a monolithic scintillation crystal and a SiPM. The signal of the probe is read out by a TOFPET2 ASIC from PETsys, which has shown good performance for PET in terms of spatial and time resolutions. Furthermore, the PETsys technology generates a trigger signal that will be used to time synchronise the probe and the scanner. The proof-of-concept of the probe will be tested in a Preclinical Super Argus PET/CT scanner for small animals located at IFIC. Preliminary simulations of the scanner and the probe under ideal conditions show a slight improvement in the position reconstruction compared to the data obtained with the scanner, therefore we expect a considerable improvement when using the probe in a total-body PET scanner. Characterisation tests of the probe have been performed with a 22Na point-like source, obtaining an energy resolution of 9.09% for the 511 keV energy peak and a temporal resolution of 619 ps after time walk correction. The next step of the project is to test the probe measuring in temporal coincidence with the scanner.

Compton Cameras are electronically collimated photon imagers suitable for sub-MeV to few MeV gamma-ray detection. Such features are desirable to enable in vivo range verification in hadron therapy, through the detection of secondary Prompt Gammas. A major concern with this technique is the poor image quality obtained when the incoming gamma-ray energy is unknown. Compton Cameras with more than two detector planes (multi-layer Compton Cameras) have been proposed as a solution, given that these devices incorporate more signal sequences of interactions to the conventional two interaction events. In particular, three interaction events convey more spectral information as they allow inferring directly the incident gamma-ray energy. A three-layer Compton Telescope based on continuous Lanthanum (III) Bromide crystals coupled to Silicon Photomultipliers is being developed at the IRIS group of IFIC-Valencia. In a previous work we proposed a spectral reconstruction algorithm for two interaction events based on an analytical model for the formation of the signal. To fully exploit the capabilities of our prototype, we present here an extension of the model for three interaction events. Analytical expressions of the sensitivity and the System Matrix are derived and validated against Monte Carlo simulations. Implemented in a List Mode Maximum Likelihood Expectation Maximization algorithm, the proposed model allows us to obtain four-dimensional (energy and position) images by using exclusively three interaction events. We are able to recover the correct spectrum and spatial distribution of gamma-ray sources when ideal data are employed. However, the uncertainties associated to experimental measurements result in a degradation when real data from complex structures are employed. Incorrect estimation of the incident gamma-ray interaction positions, and missing deposited energy associated with escaping secondaries, have been identified as the causes of such degradation by means of a detailed Monte Carlo study. As expected, our current experimental resolution and efficiency to three interaction events prevents us from correctly recovering complex structures of radioactive sources. However, given the better spectral information conveyed by three interaction events, we expect an improvement of the image quality of conventional Compton imaging when including such events. In this regard, future development includes the incorporation of the model assessed in this work to the two interaction events model in order to allow using simultaneously two and three interaction events in the image reconstruction.

A three-layer Compton Telescope, capable of measuring two and three-interaction events, is being developed at IRIS group (Image Reconstruction, Instrumentation and Simulations for medical imaging applications) of IFIC-Valencia. It is based on continuous LaBr 3 crystals coupled to SiPMs; consequently, a large number of projections can be obtained (high granularity). In order to achieve an accurate reconstruction process, precise estimations of the System Matrix and the Sensitivity Matrix are needed. Given that Monte-Carlo calculations of the aforementioned quantities are computationally expensive due to the high granularity of the imaging device, an analytical model would be advisable. The group has already proposed and assessed a model for two-interaction events. In the present work we propose a similar model for three-interaction events. Whereas three-interaction events allow to obtain the energy of incident gamma-rays without full-absorption requirement, efficiency loss and richer diversity of signal/background events must be handled. In this work we present a preliminary validation of the proposed model, by comparing its performance and predictions with Monte-Carlo simulations. Images of simulated point-like monochromatic sources, as well as a preliminary background study, are also reported.

The suitability of monolithic Lutetium Fine Silicate (LFS) continuous scintillation crystals coupled to 64-channel SiPM-TSV matrices for small animal PET has been evaluated. Three crystals of size 25.8 × 25 . 8 × 15 mm 3 were tested: LYSO white coating, LFS white coating (LFS-W) and LFS specular coating (LFS-S). Electronically collimated measurements were carried out to compare the performance of LYSO and LFS crystals. Mean energy resolutions of 14%, 17% and 19% were measured for LYSO, LFS-S and LFS-W respectively. Similar intrinsic spatial resolutions were found for all three crystals in the central region. Different versions of the light model used to estimate the interaction position of the photons in the detector have been studied. Further measurements with two detector heads of each crystal type in coincidence have also been carried out with a moveable 22Na source. A ML-MLEM image reconstruction code is used to reconstruct the data. Final position resolutions for all three configurations show similar values. Taking into account that LYSO and LFS present similar performance levels (and considering that LFS has better timing resolution than LYSO) we conclude that LFS is a valid substitute for LYSO.

Background The Godelieve Denys-Struyf method (GDS) is a motor learning intervention that may be applied in group or individualized sessions. Objective The study objective was to compare the effectiveness of routine physical therapy, group GDS (GDS-G) sessions, and group and individualized GDS (GDS-I) sessions. Design This was a cluster randomized controlled trial. Setting The study took place in 21 primary care physical therapy units (“clusters”) of the Spanish National Health Service (SNHS). Participants The participants were 461 people with subacute and chronic low back pain (LBP). Intervention Clusters were randomized into 3 groups. All participants received medical treatment and a 15-minute group education session on active management. Additional interventions were as follows: control (fifteen 40-minute sessions of transcutaneous electrical nerve stimulation, microwave treatment, and standardized exercises), GDS-G (eleven 50-minute group GDS sessions), and GDS-I (the same 11 sessions plus four 50-minute individualized GDS sessions). Measurements Primary outcomes at baseline and 2, 6, and 12 months later were LBP and pain referred down the leg (separate pain intensity numeric rating scales) and disability (Roland-Morris Questionnaire [RMQ]). Secondary outcomes were use of medication and self-reported health (mental and physical component summaries of the 12-Item Short-Form Health Survey [SF-12]). Separate linear mixed models for LBP, pain referred down the leg, and disability were developed to adjust for potential confounders. Randomization, outcome assessment, and data analyses were masked. Results At 12 months, disability improved 0.7 (95% confidence interval [CI]=−0.4, 1.8) RMQ point in the control group, 1.5 (95% CI=0.4, 2.7) RMQ points in the GDS-I group, and 2.2 (95% CI=1.2, 3.2) RMQ points in the GDS-G group. There were no differences in pain. Limitations The amount of exercise was smaller in the control group, and GDS-I sessions were provided by junior physical therapists. Conclusions The improvement in disability was slightly higher with group GDS sessions than with the program routinely used in clusters within the SNHS. Adding individualized GDS sessions eliminated this advantage. Further studies should compare the GDS with other types of exercise.

We describe a standardised mean difference statistic (d) for single-case designs that is equivalent to the usual d in between-groups experiments. We show how it can be used to summarise treatment effects over cases within a study, to do power analyses in planning new studies and grant proposals, and to meta-analyse effects across studies of the same question. We discuss limitations of this d-statistic, and possible remedies to them. Even so, this d-statistic is better founded statistically than other effect size measures for single-case design, and unlike many general linear model approaches such as multilevel modelling or generalised additive models, it produces a standardised effect size that can be integrated over studies with different outcome measures. SPSS macros for both effect size computation and power analysis are available.

The properties that might influence the sequestration of aflatoxin B1 (AfB1) were examined. Laser-diffraction, particle-size analysis (LDPSA) indicated that the particle size of the smectite influences the amount of AfB1 adsorbed. Effective adsorbent smectites disperse well under combined sodium hexametaphosphate solution and ultrasonic agitation. Particle size explained 66% of the variability for most of the samples investigated in an ‘as-received’ state. One effective adsorbent smectite was especially well aggregated and required additional physical dispersion, thus raising the correlation to 73%. Transmission electron microscope (TEM) images show typical smectites and reveal the very diverse morphology of smectites in bentonites. Thin, cloud-like smectite, in TEM images, related positively to AfB1-adsorption capacity. Particles that often fold and are usually ∼0.5 µm across seem to be optimal. The selection of criteria for evaluating these smectites provides a scientific basis for their selection to obtain reliable performance. Particle size is of particular importance as outlined below, and use of LDPSA makes it possible to perform the analysis efficiently and with precision.

The fungus Aspergillus flavus Link ex Fries can infect grains and oil seeds and develop Aflatoxin B1 (AfB1) in the fieldor in storage. Aflatoxin contamination is a serious health hazard — it is extremely toxic and hepatocarcinogenic for animals and humans. A practical approach to solve this problem is to use smectite clay as an amendment to animal feed. The objective of this research is to investigate smectite clay—AfB1 interactions by employing Fourier transform infrared (FTIR) spectroscopy to determine how clay composition influences AfB1 adsorption by smectites. When AfB1 was present in the clay, the spectral region from 1800 to 1300 cm−1 was altered, and the regions between 4000 and 1800 and 1300 and 400 cm−1 were unchanged except for the intensity in the broad region near 3400 cm−1 related to the abundance of water. The 1300–400 cm−1 region is attributed only to smectite clay properties, and it relates to the relative adsorption potential of the different smectites. Bonding between AfB1 and smectite clay appears to be in the furan rings. Other possible bonding is with the two oxygens in the coumarin ring of AfB1 and interlayer cations or their associated water molecules. The FTIR evidence of octahedral Fe in smectite and amorphous silica in the clays both indicate greater AfB1 adsorption potential. Other smectites with spectral absorption indicating predominantly Al in the octahedral positions adsorbed less AfB1.

Over the past two decades the use of smectite to suppress aflatoxin has been demonstrated for many farm animals; yet commercial marketing of smectite as an aflatoxin binder has been stymied and blending of grains containing aflatoxin persists. The suppression of aflatoxin depends of the adsorption capacity of the smectite clay binders but effectiveness is influenced by several factors. Our research indicates that smectite clays can be evaluated by the following methods: X-ray diffraction for smectite identification, Langmuir isotherm for aflatoxin binding effectiveness, structural composition by Fourier transform infrared, and cation exchange capacity for smectite quantification. Particle size determined by laser diffraction is a useful and convenient measure of smectite potential that accounts for 65% of the variability in aflatoxin adsorption by most of the clays investigated. Also, pH and Al influence are poorly understood and subjects that need further research. The organic matter content influences smectite quantitative estimates and may reduce aflatoxin adsorption. This introductory plan is intended to expedite the use of aflatoxin binders for grain while improving the performance of animals by sequestering aflatoxin permitted by regulatory action levels for aflatoxin in animal feeds.

Many consumers in the U.S. claim to prefer low fat foods, and this has encouraged the search for peanut (Arachis hypogaea L.) cultivars with low or reduced oil content. A collector's note on the low oil content of PI 576616, a Peruvian-type peanut (A. hypogaea subsp. hypogaea var. hirsuta Köhler) prompted screening of similar landraces from Mexico. PI 576633, PI 576634, PI 576635, PI 576636, PI 576637, and PI 576638 were collected in 1993 and imported to the U.S. for evaluation. In 1994, 120plants per landrace were planted in the field, using Peruvian hirsuta PI 501296 as a control. In 1995, 24 selections from each Mexican landrace, 10 selections from PI 501296, and North Carolina State Univ. (NCSU) breeding line N91026E were planted. Based on oil analysis of the lines tested in 1995, 23 low oil and eight high oil selections were planted with four NCSU virginia-type breeding lines (N91026E, N92038, N94006L, and N94014L) used as controls in 1993. Nuclear magnetic resonance (NMR) was used for oil content determination. From the 1994planting, selections from PI 576633 and PI 576638 had the lowest oil content. Five selections from PI 576634 and PI 576635 with low oil content also were identified. Earlier screening of 580 entries in the NCSU germplasm collection identified only three lines with similar oil contents. In 1995, significant (P ≤ 0.01) oil content differences were found between landraces collected from the states of Puebla and Guanajuato (482 vs. 504 g kg−1). Significant variation was found among Puebla landraces, but no differences were found among Guanajuato landraces. In 1996, significant year-to-year variation was found for some of the 31 selections. Low oil lines have been identified with the potential to be used as parents in breeding for reduced oil content.

Low molecular weight organic acids (LOAs) and fatty acids in root exudates of two lupin cultivars, Lupinus albus cv. Multolupa and L. luteus cv. Tremosilla, were determined at flowering and fruiting stages. LOAs were analysed by capillary electrophoresis. Acetic and citric acids were the most abundant, especially the latter in L. luteus at the flowering stage (5922.79 µg/g dry root). The significant decrease in acid content of both cultivars from flowering to fruiting stages was also striking. The highest levels of acetic acid were detected in L. luteus at fruiting stage (1542.03 µg/g dry root). The significant citrate production in L. luteus could be related to the low phosphorus concentration in the studied soils but not to proteoid roots, which were detected only in L. albus. The source of the LOAs detected in these exudates is also discussed, since they may be produced either by the plant or by the associated rhizobacteria. The profile of phospholipid fatty acids was determined by high-resolution GC. A high level of 18:2ω6 (a fatty acid specific to fungi) was found in exudates of L. luteus (a mycorrhizal plant) in contrast to L. albus (a non-mycorrhizal plant). Copyright © 2001 John Wiley & Sons, Ltd.

Introduction Evaluation d’un nouveau test : Acaritest ® pour la recherche des allergenes d’acariens dans des poussieres caracterisees par dosages Elisa. Methodes Trente-deux echantillons de poussieres ont ete selectionnes sur la base d’une concentration en Derp 1 et Derf 1 superieure au seuil de detection du dosage Elisa (0,039 μg/g). Les recueils de poussieres etaient realises selon les recommandations internationales. L’Acaritest ® est une methode immunochromatographique. L’echantillon migre dans une membrane de nitrocellulose et l’intensite de la reponse est proportionnelle a la quantite d’allergenes presente. Les resultats sont interpretes en comparant la ligne test (T) a la ligne controle (C) : – T > C : taux important d’acariens (> 2 μg d’allergenes du groupe 1/g de poussiere) ; – T Les tests ELISA et Acaritest ® ont ete realises selon les recommandations des fabricants. Resultats Selon l’Acaritest, 25 poussieres ont un taux important d’allergenes d’acariens, parmi elles 17 presentent une concentration > 2 μg/g en ELISA et 8 une concentration comprise entre 0,97 et 1,76 μg/g. Les 7 poussieres avec un taux d’allergenes d’acariens faible selon Acaritest, presentent des concentrations Conclusion Acaritest ® semble un dispositif interessant pour evaluer l’exposition des patients, mais des essais complementaires devront le confirmer. En effet, la mesure de l’exposition aux allergenes d’acariens est un element important dans le diagnostic de l’allergie aux acariens et dans le suivi des mesures d’eviction.

Low molecular weight organic acids (LOAs) and fatty acids in root exudates of two lupin cultivars, Lupinus albus cv. Multolupa and L. luteus cv. Tremosilla, were determined at flowering and fruiting stages. LOAs were analysed by capillary electrophoresis. Acetic and citric acids were the most abundant, especially the latter in L. luteus at the flowering stage (5922.79 micrograms/g dry root). The significant decrease in acid content of both cultivars from flowering to fruiting stages was also striking. The highest levels of acetic acid were detected in L. luteus at fruiting stage (1542.03 micrograms/g dry root). The significant citrate production in L. luteus could be related to the low phosphorus concentration in the studied soils but not to proteoid roots, which were detected only in L. albus. The source of the LOAs detected in these exudates is also discussed, since they may be produced either by the plant or by the associated rhizobacteria. The profile of phospholipid fatty acids was determined by high-resolution GC. A high level of 18:2 omega 6 (a fatty-acid specific to fungi) was found in exudates of L. luteus (a mycorrhizal plant) in contrast to L. albus (a non-mycorrhizal plant).

A study of the rhizobacteria communities of Vicia villosa was carried out during the phenological cycle. The main genera were Bacillus and Pseudomonas. The genetic divergence between Bacillus strains was studied by RAPDs-PCR and difertenciated 15 Bacillus strains groups with a genetic divergence under 10%. One strain of each of the 15 groups was randomly chosen and all were tested on 20 days old Vicia villosa plants grown in vermiculite, in order to know the effect on nitrogen fixation. The nitrogen fixation was estimated by the total nitrogen per plant.

For the past 10-15 years Brazil has undergone wide-ranging outbreaks of locusts and grasshoppers. Rhammatocerus schistocercoides (in the State of Mato Grosso/western central region, 1984-88/1991-92), Schistocerca pallens and Stiphra robusta (in Pernambuco, Paraiba, Piaui, and Rio Grande do Norte/northeastern region, 1984-86/1991-92); Rhammatocerus conspersus, R. pictus, and Staurorhectus longicornis (in Rio Grande do Sul/southern region, 1989-1992) are some of the species that have become major pests. At present there are locust/grasshopper outbreaks in at least five Brazilian States, including Mato Grosso, Paraiba, Rio Grande do Norte, and Pernambuco. Although climatic conditions play an important role in locust outbreaks, the major factors that have originated this problem in Brazil are related to changes in land management, deforestation, introduction of new crops, and to some extent the lack of monitoring and vigilance once the outbreaks are suppressed. As a result of the implementation of locust/grasshopper control campaigns in Mato Grosso (1984-1988) and Rio Grande do Sul (1991-92), it has become evident that the locust/grasshopper problem in Brazil needs a different approach. To deal properly with the situation the Government needs to establish an integrated locust/grasshopper control program, but little is known about alternative control methods, and in some cases even the ecology of the species is poorly understood. Preliminary studies on biological control and ecology of several species involved are being carried out at present in Brazil in order to undertake a long term project to establish an integrated locust/grasshopper control program. This paper outlines the present situation of the locust and grasshopper problem in Brazil. It provides up-to-date information on the most recent outbreaks and analyses those factors that may have caused an increase in locust/grasshopper populations in several states. The limitations and implications of current control campaigns are discussed, and the need to establish an integrated control program is stressed [

The three species of Mexican katydids Pterophylla beltrani (Bolivar and Bolivar 1942), Pterophylla robertsi (Hebard 1941) and Pterophylla baezi (Bolivar and Bolivar 1942) are morphologically very similar. P. beltrani and P. baezi exhibit "green" and "pink" morphs while P. robertsiwas only recorded in the green form. The shared colour forms plus the morphological similarity has caused taxonomic problems, particularly between P. beltrani and P. robertsi. Here we describe the acoustic signals of P. beltrani and P. robertsi and use these signals to clarify their taxonomy. Calling and courtship signals of both species consist of phrases made up of pulses. The highest degree of separation between the species (98%) was obtained in a discriminant analysis of the courtship signals. Phrase rate per minute, duration of pulse no. 1 and duration of pulse intervals were the most important discriminating variables. Factors causing variation in P. beltrani and P. robertsi acoustic signals are discussed and the role of acoustic signals as a Specific Mate Recognition System is stressed. Acoustic results are supported by morphometric studies which enabled a 100% separation between the species and provided diagnostic characters. Hybridization tests failed to produce any offspring. [

Pterophylla beltrani(Bolivar & Bolivar 1942) is an important forest pest in north-eastern Mexico. The species exhibits green and pink morphs. Allopatric populations differ greatly in size, wing venation and colour. To gain insight into the status of different populations, we studied variation in acoustic signals and morphometric characters within and between three allopatric populations of P. beltrani. Some divergence in acoustic signals has occurred but a discriminant analysis of the signals failed to separate the populations completely. Despite the divergence in acoustic signals males and females from all populations still recognize each other as mates and readily mate if brought together. Divergence in morphology has ocurred more rapidly than in acoustic signals as the populations can be completely separated by a morphometric analysis. Indications of genetic incompatibilities between the populations were revealed by lower numbers of eggs laid, reduced percentage of egg hatch and distorted sex ratios of interpopulation crosses. From these results we suggest that P. beltrani is one species consisting of several subspecies which are in the process of developing into separate species (