Gadjah Mada University

About: Gadjah Mada University is a education organization based out in Yogyakarta, Indonesia. It is known for research contribution in the topics: Population & Adsorption. The organization has 17307 authors who have published 21389 publications receiving 116561 citations. The organization is also known as: University of Gajah Mada & Universitas Gadjah Mada.

The global abundance of tree palms

Abstract: Aim: Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location: Tropical and subtropical moist forests. Time period: Current. Major taxa studied: Palms (Arecaceae). Methods: We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results: On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions: Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.

High numbers of granzyme B/CD8-positive tumour-infiltrating lymphocytes in nasopharyngeal carcinoma biopsies predict rapid fatal outcome in patients treated with curative intent

Abstract: This study determined whether tumour-infiltrating lymphocytes (TILs) in nasopharyngeal carcinomas (NPCs) include activated cytotoxic T lymphocytes (CTLs) and whether the numbers of activated CTLs in these biopsies are related to clinical outcome. Moreover, the study investigated whether the numbers of activated CTLs are associated with the expression of MHC class I proteins and the granzyme B antagonist PI-9 in the tumour cells. Forty-three Indonesian NPC patients (T(1-3), N(1-3), M(0)), who were treated with curative intent by radiotherapy only, were studied. Tumour-infiltrating activated CTLs were detected using antibodies against granzyme B, CD8, and CD56. Expression of MHC class I proteins and PI-9 was also determined by immunohistochemistry. Granzyme B-positive TILs were detected in all NPC biopsies. The presence of a high percentage (>25%) of granzyme B-positive TILs appeared to be a very strong predictor of a rapid fatal clinical outcome, independent of stage. Complete absence of MHC class I heavy chain expression in tumour cells was observed in 11 of 31 evaluable cases and low levels were observed in seven additional cases. No association between MHC class I expression and the numbers of granzyme B-positive TILs was observed. Expression of the granzyme B antagonist PI-9 in tumour cells was detected in three cases. It is concluded that the presence of many granzyme B-positive TILs in a selected group of Indonesian NPC patients is a strong and stage-independent marker for a rapid fatal clinical outcome.

Effect of low-frequency vibration on workpiece in EDM processes

Abstract: High-frequency vibration aided EDM has become one of the ways to increase material removal rate in EDM process, due to the flushing effect caused by vibration. However, utilizing high-frequency vibration, especially in ultrasonic range consumes a lot of setup cost. This work presents an attempt to use a low-frequency vibration on workpiece of stainless steel (SS 304) during EDM process. The workpiece was vibrated with variations of low-frequency and low-amplitude. The results show that the application of low-frequency vibration in EDM process can be used to increase the material removal rate, and decrease the surface roughness and tool wear rate.

Clinical characteristics and mortality associated with COVID-19 in Jakarta, Indonesia: A hospital-based retrospective cohort study

Abstract: Background Data on COVID-19-related mortality and associated factors from low-resource settings are scarce. This study examined clinical characteristics and factors associated with in-hospital mortality of COVID-19 patients in Jakarta, Indonesia, from March 2 to July 31, 2020. Methods This retrospective cohort included all hospitalised patients with PCR-confirmed COVID-19 in 55 hospitals. We extracted demographic and clinical data, including hospital outcomes (discharge or death). We used logistic regression to examine factors associated with mortality. Findings Of 4265 patients with a definitive outcome by July 31, 3768 (88%) were discharged and 497 (12%) died. The median age was 46 years (IQR 32–57), 5% were children, and 31% had >1 comorbidity. Age-specific mortalities were 11% (7/61) for 3) symptoms; immediate ICU admission, or intubation. Across all ages, risk of death was higher for patients with >1 comorbidity compared to those without; notably the risk was six-fold increased among patients <50 years (adjusted odds ratio 5.87, 95%CI 3.28–10.52; 27% vs 3% mortality). Interpretation Overall in-hospital mortality was lower than reported in high-income countries, probably due to younger age distribution and fewer comorbidities. Deaths occurred across all ages, with >10% mortality among children 50 years.