The Journal of Agriculture of the University of Puerto Rico
Control of black Sigatoka disease in plantains is imperative for adequate yield. Black Sigatoka i... more Control of black Sigatoka disease in plantains is imperative for adequate yield. Black Sigatoka is caused by the fungus Pseudocercospora fijiensis (Morelet) Deighton, formerly known as Mycosphaerella fijiensis Morelet. The disease does not immediately kill the plants, but by reducing the effective leaf area it interferes with photosynthesis (Churchill, 2011). If not controlled, the disease has the potential to devastate plantain fields. In Puerto Rico, the main plantain cultivar is 'Maricongo', a false-horn clone which is susceptible to black Sigatoka. Locally, a combination of synthetic pesticides and the sanitary removal of leaves, or parts of them, are used to control the disease. As suggested by Goenaga and Irizarry (2006), the use of French-type plantain clones may result in increased yield via increased production of fruits and by the tolerance of these clones to black Sigatoka. Resistance to this disease appears to be associated with French-type parents as the source of resistance in Musaceae breeding programs (Goenaga and Irizarry, 2006). A French-type tetraploid (AAAB) plantain cultivar, 'FHIA-21' was developed by the "Fundación Hondureña de Investigación Agrícola" (FHIA) at La Lima, Honduras. Major attributes of this cultivar are its high tolerance to black Sigatoka and higher yields than false-horn clones (Rowe, 1997; Hauser, 2010; Calvo, 2010); details for the plant characteristics of 'FHIA-21' were summarized in its patent (Rowe, 1997). However, 'FHIA-21' is susceptible to the Banana Streak Virus (Martínez et al., 2015), a virus that limits plant development and consequently reduces its yield potential
Proceedings of the National Academy of Sciences of the United States of America, May 8, 2018
Soil creeps imperceptibly downhill, but also fails catastrophically to create landslides. Despite... more Soil creeps imperceptibly downhill, but also fails catastrophically to create landslides. Despite the importance of these processes as hazards and in sculpting landscapes, there is no agreed-upon model that captures the full range of behavior. Here we examine the granular origins of hillslope soil transport by discrete element method simulations and reanalysis of measurements in natural landscapes. We find creep for slopes below a critical gradient, where average particle velocity (sediment flux) increases exponentially with friction coefficient (gradient). At critical gradient there is a continuous transition to a dense-granular flow rheology. Slow earthflows and landslides thus exhibit glassy dynamics characteristic of a wide range of disordered materials; they are described by a two-phase flux equation that emerges from grain-scale friction alone. This glassy model reproduces topographic profiles of natural hillslopes, showing its promise for predicting hillslope evolution over g...
ABSTRACT One of the Southern distribution limits of the Scots pine (Pinus sylvestris L.) is locat... more ABSTRACT One of the Southern distribution limits of the Scots pine (Pinus sylvestris L.) is located in the Sistema Central Range of Spain, where this tree species is present above 2000 m.a.s.l. The pine treeline is in contact with high mountain grassland and shrubland areas, defining a Mediterranean forest ecotone. Because ecotone areas are mainly climatically driven, one of these areas has been chosen for detecting ecosystem consequences of a treeline expansion into the grassland-shrubland areas. A conversion from grasslands to Scots pine forests may provoke variations in physical, chemical and biological soil properties and therefore changes in soil organic carbon (SOC) stocks. Here, we present a study carried out on the grassland-forest ecotone considering three different vegetation types: high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest. We worked on the hypothesis that different plant species compositions influence both quantity and quality soil organic matter, as a result of the different C inputs to the soil. To test this assumption, soil from the first 30 centimetres has been analysed studying total SOC stocks, different particulate organic matter pools and microbial biomass C to elucidate if there are differences in SOC quantity and quality. Results do not show significant differences (p>0.05) in total SOC stocks among vegetation types when considering the first 30 cm of the soil profile (75.9 ± 6.6 Mg C ha-1, 71.9 ± 15.3 Mg C ha-1 and 71.7 ± 14.2 Mg C ha-1 for high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest, respectively). However, there are significant differences (p<0.05) at the uppermost 5 cm (17.4 ± 2.8 Mg C ha-1, 12.1 ± 1.9 Mg C ha-1 and 13.4 ± 5.4 Mg C ha-1 for high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest, respectively), indicating differences in the SOC distribution across the soil profile. In addition, results on SOM quality analyses will be presented.
Não se admite a revogação de ato administrativo pelo uso ou pelos costumes.-As normas ou critério... more Não se admite a revogação de ato administrativo pelo uso ou pelos costumes.-As normas ou critérios de zoneamento devem ser editadas em lei, mas a individualização das áreas zoneadas para o efeito de limitações uúrbanísticas, quanto a construções, pode ser feita por decreto do Prefeito.
We formulate a formal syntax of approximate formulas for the logic with counting quantifiers, SOL... more We formulate a formal syntax of approximate formulas for the logic with counting quantifiers, SOLP, studied by us in [1], where we showed the following facts: (i) In the presence of a built-in (linear) order, SOLP can describe NP-complete problems and fragments of it capture classes like P and NL; (ii) weakening the ordering relation to an almost order (in the sense of [7]) we can separate meaningful fragments, using a combinatorial tool suited for these languages. The purpose of the approximate formulas is to provide a syntactic approximation to logics contained in SOLP with built-in order, that should be complementary of the semantic approximation based on almost orders, by producing approximating logics where problems are described within a small counting error. We introduce a concept of strong expressibility based on approximate formulas, and show that for many fragments of SOLP with built-in order, including ones that capture P and NL, expressibility and strong expressibility are equivalent. We state and prove a Bridge Theorem that links expressibility in fragments of SOLP over almost-ordered structures to strong expressibility with respect to approximate formulas for the corresponding fragments over ordered structures. A consequence of these results is that proving inexpressibility results over fragments of SOLP with built-in order can be done by proving inexpressibility over the corresponding fragments with built-in almost order, where separation proofs are easier.
Thermal fluctuations, geometric exclusion, and external driving all govern the mechanical respons... more Thermal fluctuations, geometric exclusion, and external driving all govern the mechanical response of dense particulate suspensions. Here, we measure the stress-strain response of quasi-two-dimensional flow-stabilized microsphere heaps in a regime in which all three effects are present using a microfluidic device. We observe that the elastic modulus and the mean interparticle separation of the heaps are tunable via the confining stress provided by the fluid flow. Furthermore, the measured stress-strain curves exhibit a universal nonlinear shape which can be predicted from a thermal van der Waals equation of state with excluded volume. This analysis indicates that many-body interactions contribute a significant fraction of the stress supported by the heap.
We present a second order logic of proportional quantifiers, SOLP, which is essentially a first o... more We present a second order logic of proportional quantifiers, SOLP, which is essentially a first order language extended with quantifiers that act upon second order variables of a given arity r, and count the fraction of elements in a subset of r-tuples of a model that satisfy a formula. Our logic is capable of expressing proportional versions of different problems of complexity up to NP-hard, and fragments within our logic capture complexity classes as NL and P, with auxiliary ordering relation. When restricted to monadic second order variables our logic of proportional quantifiers admits a semantic approximation based on almost linear orders, which is not as weak as other known logics with counting quantifiers, for it does not has the bounded number of degrees property. Moreover, we show in this almost ordered setting the existence of an infinite hierarchy inside our monadic language. We extend our inexpressibility result to an almost ordered (not necessarily monadic) fragment of SOLP, which in the presence of full order captures P. To obtain all our inexpressibility results we developed combinatorial games appropriate for these logics.
En el escrito se reportan las principales limitaciones que tienen los terrenos del área donde se ... more En el escrito se reportan las principales limitaciones que tienen los terrenos del área donde se ha iniciado la construcción del Nuevo Aeropuerto Internacional de la Ciudad de México (NAICM) y constituyen un obstáculo para su realización.
To explore the association between tooth loss and cognitive functioning among persons 65 years an... more To explore the association between tooth loss and cognitive functioning among persons 65 years and older. Data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (Wave 1: 1993-1994, n= 3,032; Wave 2: 1995-1996, n= 2,424; and Wave 3: 1998-1999, n= 1,967). The dependent variables were the scores from the total Mini-Mental State Examination (MMSE: score 0-30) and its global domains (memory: score 0-6; and no-memory: score 0-24). Independent variables included the number of teeth (0-12 vs. 13-32), socio-demographic characteristics, last dental office visit, medical conditions, depressive symptoms, and functional limitations which were tested for associations with the dependent variables. In bivariate analyses, participants with fewer teeth (0-12) tended to have significantly lower mean scores for memory, no-memory, and total MMSE when compared to those with more teeth (13-32), both at baseline and at follow-up. In fully adjusted longitudinal-mixed models,...
Có mo citar este artículo: Ortiz C, et al. Stents bioabsorbibles en T evaluados con tomografía de... more Có mo citar este artículo: Ortiz C, et al. Stents bioabsorbibles en T evaluados con tomografía de coherencia ó ptica. Rev Esp Cardiol. 2014.
The positron-neutrino correlation in the 0 + → 0 + β decay of 32 Ar was measured at ISOLDE by ana... more The positron-neutrino correlation in the 0 + → 0 + β decay of 32 Ar was measured at ISOLDE by analyzing the effect of lepton recoil on the shape of the narrow proton group following the superallowed decay. Our result is consistent with the Standard Model prediction; for vanishing Fierz interference we find a = 0.9989 ± 0.0052 ± 0.0036. Our result leads to improved constraints on scalar weak interactions. The positron-neutrino correlation in 33 Ar decay was measured in the same experiment; for vanishing Fierz interference we find a = 0.944 ± 0.002 ± 0.003. The 32 Ar and 33 Ar correlations, in combination with precision measurements of the half-lives, superallowed branching ratios and beta endpoint energies, will determine the isospin impurities of the superallowed transitions. These will provide useful tests of isospinviolation corrections used in deducing |V ud | which currently indicates non-unitarity of the KM matrix.
The Autoregressive Dimensional Index (ARDI) was measured in a subset of R-R recordings correspond... more The Autoregressive Dimensional Index (ARDI) was measured in a subset of R-R recordings corresponding to 257 patients from the Cardiac Arrhythmia Suppression Trial (CAST)-study, both before, and during treatment with the anti-arrhythmic drug Encainide (E). Encainide induced an average ARDI increase of 47% (P<0.001, paired t-test). <>A similar analysis with 127 patients treated with Flecainide (F) did not reveal statistical
Despite growing awareness ofthe private military company (PMC) as a dis-tinctive commercial entit... more Despite growing awareness ofthe private military company (PMC) as a dis-tinctive commercial entity due to the involvement of numerous such enter-prises in Iraq and the wider war on terror, confusion is still palpable in determining what precisely constitutes a PMC. Whilst ...
The Journal of Agriculture of the University of Puerto Rico
Control of black Sigatoka disease in plantains is imperative for adequate yield. Black Sigatoka i... more Control of black Sigatoka disease in plantains is imperative for adequate yield. Black Sigatoka is caused by the fungus Pseudocercospora fijiensis (Morelet) Deighton, formerly known as Mycosphaerella fijiensis Morelet. The disease does not immediately kill the plants, but by reducing the effective leaf area it interferes with photosynthesis (Churchill, 2011). If not controlled, the disease has the potential to devastate plantain fields. In Puerto Rico, the main plantain cultivar is 'Maricongo', a false-horn clone which is susceptible to black Sigatoka. Locally, a combination of synthetic pesticides and the sanitary removal of leaves, or parts of them, are used to control the disease. As suggested by Goenaga and Irizarry (2006), the use of French-type plantain clones may result in increased yield via increased production of fruits and by the tolerance of these clones to black Sigatoka. Resistance to this disease appears to be associated with French-type parents as the source of resistance in Musaceae breeding programs (Goenaga and Irizarry, 2006). A French-type tetraploid (AAAB) plantain cultivar, 'FHIA-21' was developed by the "Fundación Hondureña de Investigación Agrícola" (FHIA) at La Lima, Honduras. Major attributes of this cultivar are its high tolerance to black Sigatoka and higher yields than false-horn clones (Rowe, 1997; Hauser, 2010; Calvo, 2010); details for the plant characteristics of 'FHIA-21' were summarized in its patent (Rowe, 1997). However, 'FHIA-21' is susceptible to the Banana Streak Virus (Martínez et al., 2015), a virus that limits plant development and consequently reduces its yield potential
Proceedings of the National Academy of Sciences of the United States of America, May 8, 2018
Soil creeps imperceptibly downhill, but also fails catastrophically to create landslides. Despite... more Soil creeps imperceptibly downhill, but also fails catastrophically to create landslides. Despite the importance of these processes as hazards and in sculpting landscapes, there is no agreed-upon model that captures the full range of behavior. Here we examine the granular origins of hillslope soil transport by discrete element method simulations and reanalysis of measurements in natural landscapes. We find creep for slopes below a critical gradient, where average particle velocity (sediment flux) increases exponentially with friction coefficient (gradient). At critical gradient there is a continuous transition to a dense-granular flow rheology. Slow earthflows and landslides thus exhibit glassy dynamics characteristic of a wide range of disordered materials; they are described by a two-phase flux equation that emerges from grain-scale friction alone. This glassy model reproduces topographic profiles of natural hillslopes, showing its promise for predicting hillslope evolution over g...
ABSTRACT One of the Southern distribution limits of the Scots pine (Pinus sylvestris L.) is locat... more ABSTRACT One of the Southern distribution limits of the Scots pine (Pinus sylvestris L.) is located in the Sistema Central Range of Spain, where this tree species is present above 2000 m.a.s.l. The pine treeline is in contact with high mountain grassland and shrubland areas, defining a Mediterranean forest ecotone. Because ecotone areas are mainly climatically driven, one of these areas has been chosen for detecting ecosystem consequences of a treeline expansion into the grassland-shrubland areas. A conversion from grasslands to Scots pine forests may provoke variations in physical, chemical and biological soil properties and therefore changes in soil organic carbon (SOC) stocks. Here, we present a study carried out on the grassland-forest ecotone considering three different vegetation types: high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest. We worked on the hypothesis that different plant species compositions influence both quantity and quality soil organic matter, as a result of the different C inputs to the soil. To test this assumption, soil from the first 30 centimetres has been analysed studying total SOC stocks, different particulate organic matter pools and microbial biomass C to elucidate if there are differences in SOC quantity and quality. Results do not show significant differences (p&gt;0.05) in total SOC stocks among vegetation types when considering the first 30 cm of the soil profile (75.9 ± 6.6 Mg C ha-1, 71.9 ± 15.3 Mg C ha-1 and 71.7 ± 14.2 Mg C ha-1 for high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest, respectively). However, there are significant differences (p&lt;0.05) at the uppermost 5 cm (17.4 ± 2.8 Mg C ha-1, 12.1 ± 1.9 Mg C ha-1 and 13.4 ± 5.4 Mg C ha-1 for high mountain grassland-shrubland, shrubland-Scots pine high mountain forest and Scots pine mountain forest, respectively), indicating differences in the SOC distribution across the soil profile. In addition, results on SOM quality analyses will be presented.
Não se admite a revogação de ato administrativo pelo uso ou pelos costumes.-As normas ou critério... more Não se admite a revogação de ato administrativo pelo uso ou pelos costumes.-As normas ou critérios de zoneamento devem ser editadas em lei, mas a individualização das áreas zoneadas para o efeito de limitações uúrbanísticas, quanto a construções, pode ser feita por decreto do Prefeito.
We formulate a formal syntax of approximate formulas for the logic with counting quantifiers, SOL... more We formulate a formal syntax of approximate formulas for the logic with counting quantifiers, SOLP, studied by us in [1], where we showed the following facts: (i) In the presence of a built-in (linear) order, SOLP can describe NP-complete problems and fragments of it capture classes like P and NL; (ii) weakening the ordering relation to an almost order (in the sense of [7]) we can separate meaningful fragments, using a combinatorial tool suited for these languages. The purpose of the approximate formulas is to provide a syntactic approximation to logics contained in SOLP with built-in order, that should be complementary of the semantic approximation based on almost orders, by producing approximating logics where problems are described within a small counting error. We introduce a concept of strong expressibility based on approximate formulas, and show that for many fragments of SOLP with built-in order, including ones that capture P and NL, expressibility and strong expressibility are equivalent. We state and prove a Bridge Theorem that links expressibility in fragments of SOLP over almost-ordered structures to strong expressibility with respect to approximate formulas for the corresponding fragments over ordered structures. A consequence of these results is that proving inexpressibility results over fragments of SOLP with built-in order can be done by proving inexpressibility over the corresponding fragments with built-in almost order, where separation proofs are easier.
Thermal fluctuations, geometric exclusion, and external driving all govern the mechanical respons... more Thermal fluctuations, geometric exclusion, and external driving all govern the mechanical response of dense particulate suspensions. Here, we measure the stress-strain response of quasi-two-dimensional flow-stabilized microsphere heaps in a regime in which all three effects are present using a microfluidic device. We observe that the elastic modulus and the mean interparticle separation of the heaps are tunable via the confining stress provided by the fluid flow. Furthermore, the measured stress-strain curves exhibit a universal nonlinear shape which can be predicted from a thermal van der Waals equation of state with excluded volume. This analysis indicates that many-body interactions contribute a significant fraction of the stress supported by the heap.
We present a second order logic of proportional quantifiers, SOLP, which is essentially a first o... more We present a second order logic of proportional quantifiers, SOLP, which is essentially a first order language extended with quantifiers that act upon second order variables of a given arity r, and count the fraction of elements in a subset of r-tuples of a model that satisfy a formula. Our logic is capable of expressing proportional versions of different problems of complexity up to NP-hard, and fragments within our logic capture complexity classes as NL and P, with auxiliary ordering relation. When restricted to monadic second order variables our logic of proportional quantifiers admits a semantic approximation based on almost linear orders, which is not as weak as other known logics with counting quantifiers, for it does not has the bounded number of degrees property. Moreover, we show in this almost ordered setting the existence of an infinite hierarchy inside our monadic language. We extend our inexpressibility result to an almost ordered (not necessarily monadic) fragment of SOLP, which in the presence of full order captures P. To obtain all our inexpressibility results we developed combinatorial games appropriate for these logics.
En el escrito se reportan las principales limitaciones que tienen los terrenos del área donde se ... more En el escrito se reportan las principales limitaciones que tienen los terrenos del área donde se ha iniciado la construcción del Nuevo Aeropuerto Internacional de la Ciudad de México (NAICM) y constituyen un obstáculo para su realización.
To explore the association between tooth loss and cognitive functioning among persons 65 years an... more To explore the association between tooth loss and cognitive functioning among persons 65 years and older. Data from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (Wave 1: 1993-1994, n= 3,032; Wave 2: 1995-1996, n= 2,424; and Wave 3: 1998-1999, n= 1,967). The dependent variables were the scores from the total Mini-Mental State Examination (MMSE: score 0-30) and its global domains (memory: score 0-6; and no-memory: score 0-24). Independent variables included the number of teeth (0-12 vs. 13-32), socio-demographic characteristics, last dental office visit, medical conditions, depressive symptoms, and functional limitations which were tested for associations with the dependent variables. In bivariate analyses, participants with fewer teeth (0-12) tended to have significantly lower mean scores for memory, no-memory, and total MMSE when compared to those with more teeth (13-32), both at baseline and at follow-up. In fully adjusted longitudinal-mixed models,...
Có mo citar este artículo: Ortiz C, et al. Stents bioabsorbibles en T evaluados con tomografía de... more Có mo citar este artículo: Ortiz C, et al. Stents bioabsorbibles en T evaluados con tomografía de coherencia ó ptica. Rev Esp Cardiol. 2014.
The positron-neutrino correlation in the 0 + → 0 + β decay of 32 Ar was measured at ISOLDE by ana... more The positron-neutrino correlation in the 0 + → 0 + β decay of 32 Ar was measured at ISOLDE by analyzing the effect of lepton recoil on the shape of the narrow proton group following the superallowed decay. Our result is consistent with the Standard Model prediction; for vanishing Fierz interference we find a = 0.9989 ± 0.0052 ± 0.0036. Our result leads to improved constraints on scalar weak interactions. The positron-neutrino correlation in 33 Ar decay was measured in the same experiment; for vanishing Fierz interference we find a = 0.944 ± 0.002 ± 0.003. The 32 Ar and 33 Ar correlations, in combination with precision measurements of the half-lives, superallowed branching ratios and beta endpoint energies, will determine the isospin impurities of the superallowed transitions. These will provide useful tests of isospinviolation corrections used in deducing |V ud | which currently indicates non-unitarity of the KM matrix.
The Autoregressive Dimensional Index (ARDI) was measured in a subset of R-R recordings correspond... more The Autoregressive Dimensional Index (ARDI) was measured in a subset of R-R recordings corresponding to 257 patients from the Cardiac Arrhythmia Suppression Trial (CAST)-study, both before, and during treatment with the anti-arrhythmic drug Encainide (E). Encainide induced an average ARDI increase of 47% (P<0.001, paired t-test). <>A similar analysis with 127 patients treated with Flecainide (F) did not reveal statistical
Despite growing awareness ofthe private military company (PMC) as a dis-tinctive commercial entit... more Despite growing awareness ofthe private military company (PMC) as a dis-tinctive commercial entity due to the involvement of numerous such enter-prises in Iraq and the wider war on terror, confusion is still palpable in determining what precisely constitutes a PMC. Whilst ...
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