RecruitNet: A global database of plant recruitment networks.

Plant recruitment interactions (i.e., what recruits under what) shape the composition, diversity, and structure of plant communities. Despite the huge body of knowledge on the mechanisms underlying recruitment interactions among species, we still know little about the structure of the recruitment networks emerging in ecological communities. Modeling and analyzing the community-level structure of plant recruitment interactions as a complex network can provide relevant information on ecological and evolutionary processes acting both at the species and ecosystem levels. We report a data set containing 143 plant recruitment networks in 23 countries across five continents, including temperate and tropical ecosystems. Each network identifies the species under which another species recruits. All networks report the number of recruits (i.e., individuals) per species. The data set includes >850,000 recruiting individuals involved in 118,411 paired interactions among 3318 vascular plant species across the globe. The cover of canopy species and open ground is also provided. Three sampling protocols were used: (1) The Recruitment Network (RN) protocol (106 networks) focuses on interactions among established plants ("canopy species") and plants in their early stages of recruitment ("recruit species"). A series of plots was delimited within a locality, and all the individuals recruiting and their canopy species were identified; (2) The paired Canopy-Open (pCO) protocol (26 networks) consists in locating a potential canopy plant and identifying recruiting individuals under the canopy and in a nearby open space of the same area; (3) The Georeferenced plot (GP) protocol (11 networks) consists in using information from georeferenced individual plants in large plots to infer canopy-recruit interactions. Some networks incorporate data for both herbs and woody species, whereas others focus exclusively on woody species. The location of each study site, geographical coordinates, country, locality, responsible author, sampling dates, sampling method, and life habits of both canopy and recruit species are provided. This database will allow researchers to test ecological, biogeographical, and evolutionary hypotheses related to plant recruitment interactions. There are no copyright restrictions on the data set; please cite this data paper when using these data in publications.

Adaptations facilitate the invasion of Cylindropuntia rosea (DC.) Backeb. (Cactaceae) in the highlands of southwestern Saudi Arabia.

The colonization and expansion of any plant species into a novel environment depend on its structural and functional characteristics. Therefore, developing better control measures for any invasive plant species requires examining and understanding the mechanisms underlying its reproduction and adaptation to the environment it invades. Recently, a novel exotic species Cylindropuntia rosea (DC.) Backeb. has been identified in Baljurashi, Al-Baha province, in southwestern Saudi Arabia. Reports suggest that this species may become invasive with the current rate of habitat expansion in Baljurashi. Although C. rosea is an important invasive species, most of its morpho-anatomical and physiological characteristics have not been examined. Therefore, the aim of this study was to investigate the morpho-anatomical and related physiological adaptations of C. rosea in its new habitats in the southwestern highlands of Saudi Arabia. We observed that the species is well-equipped for invasion with traits to handle semi-arid conditions, including some morphological and anatomical features, CAM photosynthetic pathway, high growth rate, and highly effective defense mechanisms against herbivores and insects. These morpho-anatomical and physiological characteristics contribute to the high invasiveness of this species in Saudi Arabia.

Island biogeography, competition, and abiotic filtering together control species richness in habitat islands formed by nurse tree canopies in an arid environment.

The theory of island biogeography predicts that island size is a key predictor of community species richness. Islands can include any habitat surrounded environments that are inhospitable to the resident species. In arid environments, nurse trees act as islands in an environment uninhabitable to many plant species, and the size of the canopy controls the size of the understory plant community. We predicted that plant species richness will be affected by the area of the habitat and decrease with habitat isolation. We sampled the adult and seedling plant communities at canopy center, canopy edge, and outside canopy microhabitats. We found that species richness in both adult and seedling communities increases with increasing island area. However, richness in seedling communities was greater than in adult communities, and this effect was greatest at the canopy center microhabitat. Competition has been demonstrated to be more important in controlling species distributions near the canopy center, and stress is more important near the canopy edge. Thus, our results suggest that neutral forces, biotic interactions, and abiotic filtering act together to control species richness in these island communities.

Floristic composition of Jandaf Mountain as biodiversity hotspot area in southwestern Saudi Arabia.

Arid environments around the world are characterized by lower plant diversity. However, some specific locations have relatively high species richness and have significant importance in terms of vegetation structure and plant diversity. Jabal Al-Jandaf is located in an arid area within the eastern side of mountainous region in the southwest of Saudi Arabia. It consists of valleys, lower plain and upper plain habitats with unique and diverse vegetation. These habitats range from 1000 m above sea level near the Tarj valley to 1910 m at the summit. In this study, we conducted a first survey of the floristic diversity at Jandaf Mountain. Furthermore, we applied the criteria of the Important Plant Area (IPA) and the High Conservation Value (HCV) approaches to assess whether the plant community at Jandaf Mountain qualifies as a significant conservation area. We found that the study area has great plant diversity with plant composition varying among the different habitats (e.g., valleys, upper and lower elevations) within the study area. We recorded 118 species from 97 genera belonging to 42 families, including endemic (e.g. Aloe pseudorubroviolacea), near-endemic (e.g. Monolluma quadrangular), and endangered species (e.g. Dracaena serrulata, Combretum molle, and Moringa peregrine). The plant diversity at Jandaf Mountain achieves the criteria outlined in the IPA and HCV approaches. Therefore, we conclude that Jandaf Mountain has a unique vegetation structure, and the area qualifies for conservation as a high value area for biodiversity and conservation of global significance.

Natural plant species inventory of hotspot areas in Arabian Peninsula: Southwest Al-Baha region, Saudi Arabia.

Plant hotspot areas are the areas that are very rich in plant species diversity. These areas have a priority for conservation. To highlight the plant diversity for nature conservation purposes a case study in Al Baha region, Saudi Arabia is presented, in which the importance of the natural vegetation and flora of one of the hotspot areas of Saudi Arabia is evaluated through the explanation of its natural plant species. A survey study has been conducted in an area of 167.6 km2, a 97 sample each with 20X20 m were laid out covering the whole ecological zones of the study site. Data of flora, vegetation cover and topography were gathered from each sample site. The study revealed about 319 plant species belonging to 228 genera and 75 families. Two species were found endemic to Saudi Arabia, 14 were endemics to Arabian Peninsula, and five were regional endemics that are only found in East Africa and Arabian Peninsula, while 39 species are rare and endangered.

Cardiac arrhythmias in hospitalized patients with COVID-19: A prospective observational study in the western United States.

Arrhythmias have been reported frequently in COVID-19 patients, but the incidence and nature have not been well characterized. Patients admitted with COVID-19 and monitored by telemetry were prospectively enrolled in the study. Baseline characteristics, hospital course, treatment and complications were collected from the patients' medical records. Telemetry was monitored to detect the incidence of cardiac arrhythmias. The incidence and types of cardiac arrhythmias were analyzed and compared between survivors and non-survivors. Among 143 patients admitted with telemetry monitoring, overall in-hospital mortality was 25.2% (36/143 patients) during the period of observation (mean follow-up 23.7 days). Survivors were less tachycardic on initial presentation (heart rate 90.6 ± 19.6 vs. 99.3 ± 23.1 bpm, p = 0.030) and had lower troponin (peak troponin 0.03 vs. 0.18 ng/ml. p = 0.004), C-reactive protein (peak C-reactive protein 97 vs. 181 mg/dl, p = 0.029), and interleukin-6 levels (peak interleukin-6 30 vs. 246 pg/ml, p = 0.003). Sinus tachycardia, the most common arrhythmia (detected in 39.9% [57/143] of patients), occurred more frequently in non-survivors (58.3% vs. 33.6% in survivors, p = 0.009). Premature ventricular complexes occurred in 28.7% (41/143), and non-sustained ventricular tachycardia in 15.4% (22/143) of patients, with no difference between survivors and non-survivors. Sustained ventricular tachycardia and ventricular fibrillation were not frequent (seen only in 1.4% and 0.7% of patients, respectively). Contrary to reports from other regions, overall mortality was higher and ventricular arrhythmias were infrequent in this hospitalized and monitored COVID-19 population. Either disease or management-related factors could explain this divergence of clinical outcomes, and should be urgently investigated.

Assessing the response of five tree species to air pollution in Riyadh City, Saudi Arabia, for potential green belt application.

Tree species (including Eucalyptus camaldulensis, Ziziphus spina-christi, Albizia lebbeck, Prosopis juliflora, Pithecellobium dulce, and Ficus altissima) were investigated to elucidate their appropriates for green belt application. Leaf samples were collected from four different locations in Riyadh: (1) residential; (2) dense traffic; (3) industrial; and (4) reference sites located approximately 20 km away from the city of Riyadh. Leaves collected from the industrial site showed the highest leaf area reduction. The smallest reduction of leaf areas was observed for F. altissima (11.6%), while the highest reduction was observed for P. juliflora (34.8%). Variations in the air pollution tolerance index (APTI) coupled with the anticipated performance index (API) for each species were examined. The APTI value of Z. spina-christi was highest (58.5) at the industrial site while the lowest APTI value was for P. juliflora (14) at the reference site. Correlation coefficient and linear regression analyses determined that the correlation between the ascorbic acid content and APTI is positive and significantly strong. Our findings indicate that urban green planning in Riyadh should include growing F. altissima on roadsides as well as in heavy industrial locations followed by Z. spina-christi and A. lebbeck according to their API and APTI performances.

Effects of plant-plant interactions and herbivory on the plant community structure in an arid environment of Saudi Arabia.

There is currently considerable evidence support that plant community structures are driven by plant-plant interactions (e.g., competition and facilitation). In contrast, there is also evidence demonstrating that plant community structure is affected by the impact of consumer pressure (e.g., grazing). In this study, 15 and 10 Acacia gerrardii nurse plants were selected inside and outside Sudyrah natural reserve (protected) area in western Saudi Arabia, respectively. The understory vegetation abundance (e.g. cover and density) was measured among quadrats around the nurse trees in both protected and unprotected areas to examine the impact of grazing and the positive interaction on the understory species. I found that understory vegetation associated with nurse trees (A. gerrardii) has been driven by both the positive impact of nurse plant and the grazing. Although the understory vegetation was positively affected by the impact of facilitation, the composition of such vegetation has been changed due to the impact of herbivory.

Bortezomib sensitizes multiple myeloma to NK cells via ER-stress-induced suppression of HLA-E and upregulation of DR5.

Although the proteasome inhibitor bortezomib has significantly improved the survival of patients with multiple myeloma (MM), the disease remains fatal as most patients eventually develop progressive disease. Recent data indicate that MM cells can evade bortezomib-induced cell death by undergoing autophagy as a consequence of endoplasmatic reticulum (ER)-stress induced by proteasome inhibition. Here we show that bortezomib sensitizes MM cells to NK cell killing via two distinct mechanisms: a) upregulation of the TRAIL death receptor DR5 on the surface of MM cells and b) ER-stress induced reduction of cell surface HLA-E. The latter mechanism is completely novel and was found to be exclusively controlled by the inhibitory receptor NKG2A, with NKG2A single-positive (NKG2ASP) NK cells developing a selective augmentation in tumor killing as a consequence of bortezomib-induced loss of HLA-E on the non-apoptotic MM cells. In contrast, the expression of classical HLA class I molecules remained unchanged following bortezomib exposure, diminishing the augmentation of MM killing by NK cells expressing KIR. Further, we found that feeder cell-based ex vivo expansion of NK cells increased both NK cell TRAIL surface expression and the percentage of NKG2ASP NK cells compared to unexpanded controls, substantially augmenting their capacity to kill bortezomib-treated MM cells. Based on these findings, we hypothesize that infusion of ex vivo expanded NK cells following treatment with bortezomib could eradicate MM cells that would normally evade killing through proteasome inhibition alone, potentially improving long-term survival among MM patients.

Optimizing coffee cultivation and its impact on economic growth and export earnings of the producing countries: The case of Saudi Arabia.

Coffee is one of the historical socioeconomic crops. It has received an increasing attention at the global level, due to its positive interlinkage with the economic growth and on the gross domestic product for most of the producing countries, particularly, developing and least developed countries. Saudi Arabia is one of the coffee producing countries that has a relative comparative advantage of coffee cultivation. Yet, coffee cultivation has not received as much attention in Saudi Arabia as that of producing countries around the world. This study aims to assess the current state of coffee cultivation in Saudi Arabia and to investigate the potential to optimize coffee cultivation in Saudi Arabia that maximizes the net national economic return and export earnings, given limitation of cultivated areas, local market activities, and international trade activities. The study statistically analyzed primary data collected from around (65) coffee farms and traders in the study regions at the south and southwest Saudi Arabia, and optimized coffee cultivation in Saudi Arabia using LINGO optimization software. Empirical results of the study revealed the great potential of Saudi Arabia to expand coffee cultivation at south and southwest regions to meet the escalating local demand and to increase its share at the world market up to 2%. Optimization of coffee cultivation in Saudi Arabia showed a high potential to meet the local demand for coffee by producing 80.07 thousand tons grown over 2861.78 hectares and to generate a net return equivalent to $395.72 million a year, which is equivalent to $138.28 thousand per hectare and $4.94 thousand per ton of coffee. Optimizing coffee cultivation will play a substantial role to increase market share of Saudi Arabia to about 1-2% of the world market by increasing its export volume, respectively, to about 69.66 and 112.56 thousand tons, the national net economic return by about $395.86 and $395.95 million a year, and the export earnings of coffee by about $219.43-354.57 million a year, which in turns, will serve the national strategic trend to diversify the economic base and lower the dependency of incomes generated from oil exportation.

Early Readmission Risk Identification for Hospitalized Older Adults With Decompensated Heart Failure.

The current study evaluated risk factors of early hospital readmission in geriatric patients with acute heart failure (HF) and analyzed 2,279 consecutively hospitalized older adults with decompensated HF from November 2013 to October 2014 across 15 U.S. hospitals. The eTracker-HF was designed to make risk factors known to treating clinicians in electronic health records. Multilevel multivariate logistic regression was applied to examine the association between risk factors and all-cause and HF 30-day readmission rates. All-cause and HF 30-day readmission rates were 22.3% and 9.8%, respectively. Old age, non-White ethnicity, delirium, physical impairment, ejection fraction <40%, advanced chronic kidney disease, and previous myocardial infarction were associated with all-cause and HF readmission. Home health care use was inversely associated with early readmission. In addition to demographic and cardiovascular risk factors, geriatric syndromes were associated with early readmission. Discharge to home health care may reduce early readmission in these patients. [Res Gerontol Nurs. 2018; 11(4):190-197.].

Preventive Effects of Pre- and Intra-operative Marcaine, Lidocaine, and Marcaine Plus Lidocaine on Pain Relief in Lumbar Disc Herination Open Surgery.

BACKGROUND: As marcaine is administered to a great extent due to minor complications and reasonable expenses and as discectomy is prevalently used in Iran, this study makes a comparison between effect of marcaine alone, lidocaine alone, and marcaine plus lidocaine on pain relief of patients undergoing lumbar disc open surgery. MATERIALS AND METHODS: In a clinical trial study, 192 patients were selected and randomly divided into four groups. Patients in Groups 1-4 received 0.5 ml marcaine during surgery, 5 ml lidocaine 2% before incision, 5 ml lidocaine 2% before incision plus 5 ml marcaine during surgey and normal saline, respectively. After patients gained knowledge of visual analog scale (VAS) criteria, their severity of pain was measured and was recorded in their profiles, along with demographic details and history of diseases. After surgery and their transfer to their rooms, their severity of pain was measured and recorded again by using VAS criteria. Finally, difference between the four groups was compared by SPSS software. RESULTS: The mean (±standard deviation) of postoperative pain in marcaine + lidocaine, marcaine, lidocaine, and normal saline was 3.5 ± 1.3, 3.5 ± 1.6, 36.1.9, and 4.2 ± 1.8, respectively, and we did not observe any significant difference in severity of pain after surgery in these groups (P = 0.15). The highest and lowest degree of satisfaction occurred in marcaine-lidocaine group and control group, respectively, (40 patients [83.3%] vs. 25 patients [52.1%]). CONCLUSION: Lidocaine-marcaine treatment reduces the need to opiates in cases of postoperative pain relief of discectomy and provides patients with great satisfaction.

Epidemiologic and Demographic Features, Therapeutic Intervention and Prognosis of the Patients with Cerebral Aneurysm.

BACKGROUND: Cerebral aneurysms are a kind of cardiovascular diseases which are accompanied with high morbidity and mortality due to rupturing and causing subarachnoid hemorrhages. The current study aimed to determine epidemiologic and demographic features and prognosis of patients with cerebral aneurysms. MATERIALS AND METHODS: In this cross-sectional study, 465 patients with cerebral aneurysms hospitalized in Al-Zahra Hospital were studied. The required information including demographic, epidemiologic, and clinical features of the disease were extracted from their records. The obtained data were analyzed using SPSS software and the factors associated with the prognosis of the disease were determined. RESULTS: Four hundred and sixty-five cases with cerebral aneurysm undergoing surgery were investigated. The mean age of the patients was 48 ± 14 years whereas 216 cases (46.5%) were male and 249 (53.5%) were female. Two hundred and thirty-seven patients (51%) remitted completely while the disease caused moderate disability in 84 cases (18.1%), severe disability in 24 ones (5.2%) and vegetative state in 9 cases (1.9%) and mortality in 57 ones while it was unknown in 54 cases (11.6%). In terms of the age of patient, WFNS index, anatomical position of aneurysm, type of aneurysm lesion, the incidence season of the disease, type of postoperative complications, family history and operative approach, the disease outcome had a significant difference while gender, ethnicity, and risk factors had no significant effect on the disease outcome. CONCLUSIONS: According to the type of aneurysm, the incidence position of the aneurysm and other epidemiologic, demographic, and clinical features, providing the prevention and treatment strategies is necessary.

Competition and facilitation structure plant communities under nurse tree canopies in extremely stressful environments.

Nurse plant facilitation in stressful environments can produce an environment with relatively low stress under its canopy. These nurse plants may produce the conditions promoting intense competition between coexisting species under the canopy, and canopies may establish stress gradients, where stress increases toward the edge of the canopy. Competition and facilitation on these stress gradients may control species distributions in the communities under canopies. We tested the following predictions: (1) interactions between understory species shift from competition to facilitation in habitats experiencing increasing stress from the center to the edge of canopy of a nurse plant, and (2) species distributions in understory communities are controlled by competitive interactions at the center of canopy, and facilitation at the edge of the canopy. We tested these predictions using a neighbor removal experiment under nurse trees growing in arid environments. Established individuals of each of four of the most common herbaceous species in the understory were used in the experiment. Two species were more frequent in the center of the canopy, and two species were more frequent at the edge of the canopy. Established individuals of each species were subjected to neighbor removal or control treatments in both canopy center and edge habitats. We found a shift from competitive to facilitative interactions from the center to the edge of the canopy. The shift in the effect of neighbors on the target species can help to explain species distributions in these canopies. Canopy-dominant species only perform well in the presence of neighbors in the edge microhabitat. Competition from canopy-dominant species can also limit the performance of edge-dominant species in the canopy microhabitat. The shift from competition to facilitation under nurse plant canopies can structure the understory communities in extremely stressful environments.

Reproductive efficiency and shade avoidance plasticity under simulated competition.

Plant strategy and life-history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life-history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition. We tested (1) how simulated competition influences reproductive efficiency and competitive ability (CA) of different plant life histories and growth forms; (2) whether life history or growth form is associated with CA; (3) whether shade avoidance plasticity is connected to reproductive efficiency under simulated competition. We examined plastic responses of 11 herbaceous species representing different life histories and growth forms to simulated competition (spectral shade). We found that both annual and perennial plants invested more to reproduction under simulated competition in accordance with life-history theory predictions. There was no significant difference between competitive abilities of different life histories, but across growth forms, erect species expressed greater CA (in terms of leaf number) than other growth forms. We also found that shade avoidance plasticity can increase the reproductive efficiency by capitalizing on the early life resource acquisition and conversion of these resources into reproduction. Therefore, we suggest that a reassessment of the interpretation of shade avoidance plasticity is necessary by revealing its role in reproduction, not only in competition of plants.