Nitrogen and phosphorus accumulation and remobilization of durum wheat as affected by soil gravel content

Soil gravel content affects many soil physical properties, as well as crop yield. Little is known regarding the influence of soil gravel content on growth and nutrient uptake of durum wheat (Triticum durum Desf.). The accumulation of nitrogen and phosphorous during the vegetative and reproductive periods and the contribution of pre-anthesis assimilates to grain N and P con- tent have been evaluated in two durum wheat varieties grown on soils with 0, 10, 20 and 30% gravel content. The two varieties showed similar behaviour and the increase of soil gravel de- creased plant biomass during the entire biological cycle. Nitrogen and P concentration of all plant parts was not affected by soil gravel content, while N and P content was greatly reduced, owing to the effect on dry matter yield. Post-anthesis accumulation and remobilization of N and P were greatly reduced: the decrease from gravel-free soil to 30% gravel content was about 41 kg N ha–1 and 4 kg P ha–1 for the former and 14 kg N ha–1 and 2 kg P ha–1 for the latter. The differences in growth rate were attributed to differences in development of the root system due to the restricted soil volume

Life Cycle Assessment di sistemi per le auto elettriche

Lo sviluppo della trazione elettrica stradale, in particolare con l\u2019uso di batterie al litio, \ue8 uno degli approcci pi\uf9 promettenti alle problematiche di carattere ambientale e per la diversificazione delle fonti di energia. Il lavoro descrive una delle attivit\ue0 svolta nell\u2019ambito dell\u2019Accordo di Programma Ministero dello Sviluppo Economico ed ENEA sulla ricerca del sistema elettrico. In particolare l\u2019ENEA e il Dipartimento dell\u2019Energia dell\u2019Universit\ue0 di Palermo hanno condotto uno studio di LCA delle batterie per autotrazione per valutare le prestazioni energetico-ambientali di questi sistemi

Grain yield of durum wheat as affected by waterlogging at tillering

Waterlogging is one of the limiting factors influencing durum wheat (Triticum durum L.) production. In this paper we investigated the impact of seven waterlogging durations of 4, 8, 12, 16, 20, 40, and 60 days, imposed at 3-leaf and 4-leaf growth stages, on grain yield, grain yield components, straw and root dry weight and nitrogen concentration of grain, straw, and roots of two varieties of durum wheat. Grain yield of both varieties showed a significant reduction only when waterlogging was prolonged to more than 20 days, and 40-d and 60-d waterlogging reduced grain yield by 19% and 30%. Waterlogging depressed grain yield preventing many culms from producing spikes. It slowed down spikelet formation, consequently reducing the number of spikelets per spike, and reduced floret formation per spikelet, thus reducing the number of kernels per spike

Ants modulate stridulatory signals depending on the behavioural context

Insect societies require an effective communication system to coordinate members’ activities. Although eusocial species primarily use chemical communication to convey information to conspecifics, there is increasing evidence suggesting that vibroacoustic communication plays a significant role in the behavioural contexts of colony life. In this study, we sought to determine whether stridulation can convey information in ant societies. We tested three main hypotheses using the Mediterranean ant Crematogaster scutellaris: (i) stridulation informs about the emitter’caste; (ii) workers can modulate stridulation based on specific needs, such as communicating the profitability of a food resource, or (iii) behavioural contexts. We recorded the stridulations of individuals from the three castes, restrained on a substrate, and the signals emitted by foragers workers feeding on honey drops of various sizes. Signals emitted by workers and sexuates were quantitatively and qualitatively distinct as was stridulation emitted by workers on different honey drops. Comparing across the experimental setups, we demonstrated that signals emitted in different contexts (restraining vs feeding) differed in emission patterns as well as certain parameters (dominant frequency, amplitude, duration of chirp). Our findings suggest that vibrational signaling represents a flexible communication channel paralleling the well-known chemical communication system

Mixing Improvement in a T-Shaped Micro-Junction through Small Rectangular Cavities

The T-shaped micro-junction is among the most used geometry in microfluidic applications, and many design modifications of the channel walls have been proposed to enhance mixing. In this work, we investigate through numerical simulations the introduction of one pair of small rectangular cavities in the lateral walls of the mixing channel just downstream of the confluence region. The aim is to preserve the simple geometry that has contributed to spread the practical use of the T-shaped micro-junction while suggesting a modification that should, in principle, work jointly with the vortical structures present in the mixing channel, further enhancing their efficiency in mixing without significant additional pressure drops. The performance is analyzed in the different flow regimes occurring by increasing the Reynolds number. The cavities are effective in the two highly-mixed flow regimes, viz., the steady engulfment and the periodic asymmetric regimes. This presence does not interfere with the formation of the vortical structures that promote mixing by convection in these two regimes, but it further enhances the mixing of the inlet streams in the near-wall region of the mixing channel without any additional cost, leading to better performance than the classical configuration

Laparoscopic versus open distal gastrectomy for locally advanced gastric cancer in middle–low-volume centers in Western countries. a propensity score matching analysis

Background: Gastrectomy with D2 lymphadenectomy is the standard treatment for patients with resectable gastric cancer. Laparoscopic distal gastrectomy (LDG) is routinely performed for early gastric cancer, and its indications are increasing even for locally advanced gastric cancer. The aim of this study is to compare two middle–low-volume centers in Western countries experience on LDG versus open distal gastrectomy (ODG) for locally advanced gastric cancer in terms of surgical and oncological outcomes. Methods: We reviewed the data of 123 consecutive patients that underwent LDG and ODG with D2 lymphadenectomy between 2009 and 2014. Among them, 91 were eligible for inclusion (46 LDG and 45 ODG). After propensity score matching analysis, using a 1:1 case-control match, 34 patients were stratified for each group. Results: The mean operative time was significantly longer in the LDG group (257.2 vs. 197.2, p < 0.001). No differences were observed in terms of intraoperative blood loss, average number of lymph nodes removed, and lymph node metastases. The postoperative morbidity was comparable in the two groups. LDG group had a significant faster bowel canalization and soft oral intake (p < 0.001). The 5-year overall and disease-free survival were higher for patients treated by laparoscopy, but the post-hoc subgroups analysis revealed that the advantage of LDG was significant just in N0 and stage IB-II patients, whereas N+ and stage III patient’s survival curves were perfectly superimposable. Conclusions: LDG for locally advanced gastric cancer seems to be feasible and safe with surgical and long-term oncological outcomes comparable with open surgery, even in medium–low-volume centers

Where is the pseudoscalar glueball ?

The pseudoscalar mesons with the masses higher than 1 GeV are assumed to belong to the meson decuplet including the glueball as the basis state supplementing the standard $SU(3)_F$ nonet of light $q\bar{q}$ states $(u,d,s)$. The decuplet is investigated by means of an algebraic approach based on hypothesis of vanishing the exotic $SU(3)_F$ commutators of "charges" and their time derivatives. These commutators result in a system of equations determining contents of the isoscalar octet state in the physical isoscalar mesons as well as the mass formula including all masses of the decuplet: $\pi(1300)$, K(1460), $\eta(1295)$, $\eta(1405)$ and $\eta(1475)$. The physical isoscalar mesons $\eta_i$, are expressed as superpositions of the "ideal" $q\bar{q}$ states ($N$ and $S$) and the glueball $G$ with the mixing coefficient matrix following from the exotic commutator restrictions. Among four one-parameter families of the calculated mixing matrix (numerous solutions result from bad quality of data on the $\pi(1300)$ and K(1460) masses) there is one family attributing the glueball-dominant composition to the $\eta(1405)$ meson. Similarity between the pseudoscalar and scalar decuplets, analogy between the whole spectra of the $0^{-+}$ and $0^{++}$ mesons and affinity of the glueball with excited $q\bar{q}$ states are also noticed.Comment: 18 pp., 2. figs., 2 tabs.; Published version. One of the authors withdraws his nam