Association between pathological complete response and tumor location in patients with rectal cancer after neoadjuvant chemoradiotherapy, a prospective cohort study

Background: Colorectal cancers are the third common malignancies after lung and breast neoplasms. Some contributing factors for pathological complete response (pCR) to neoadjuvant therapy of rectal cancer have been defined. Despite various studies in this era, there are few studies on the location of tumors. Objectives: Regarding the high prevalence of colorectal cancer in Iran and the importance of neoadjuvant chemoradiation for survival and morbidity, this study was carried out to determine the association between pathologic complete response and tumor location in patients with rectal cancer after neoadjuvant chemoradiotherapy. Methods: In this prospective cohort, 100 cases with rectal adenocarcinoma from 2017 to 2019 were enrolled. Distance between anal verge and tumor was measured by clinical examination, colonoscopy, endo-sonography, and MRI. Tumors were defined as distal (less than 5 cm from the anal verge) and none distal (more than 5 cm from the anal verge). Another subdivision was inferior (0-4.99 cm), middle (5-9.99 cm), and superior (10-15 cm). The pathological response was compared across the groups. Results: In this study, the pCR was seen in 30. In univariate analysis body mass index (BMI), grade, N-stage, and distance from anal verge were related to pCR. In cases with BMI over 25 kg/m2 and in tumors with low to medium grade N0/N1, and distance less than 5 cm from the anal verge (low lying tumors) the pCR to neoadjuvant treatment was higher. In multivariate analysis tumor grade, N stage, and distance from anal verge were still related to pCR. Conclusions: According to the obtained results in this study, there may be some association between rectal tumor location and pathologic complete response. © 2021, Author(s)

Kemampuan Menghitung Integral Tak Tentu dan Tentu dari Fungsi Aljabar Sederhana Serta Penerapannya dalam Menghitung Luas Daerah di Bawah Kurva Siswa Kelas XII IPS SMA Syaichona Cholil Samarinda Tahun Ajaran 2017/2018

Suatu penelitian deskriptif kuantitatif yang bertujuan untuk mengetahui kemampuan menghitung integral tak tentu dan tentu dari fungsi aljabar sederhana serta penerapannya dalam menghitung luas daerah di bawah kurva siswa kelas XII IPS SMA Syaichona Cholil Samarinda Tahun Ajaran 2017/2018. Penelitian ini dilakukan pada bulan Desember 2017, dengan subjek penelitian sebanyak 47 siswa, dan dengan objek penelitian yaitu kemampuan menghitung integral tak tentu dan tentu dari fungsi aljabar sederhana serta penerapannya dalam menghitung luas daerah di bawah kurva. Instrumen yang digunakan untuk mengumpulkan data dalam penelitian ini adalah tes tertulis berupa soal uraian sebanyak 6 butir soal. Teknik analisis data meliputi penilaian hasil tes kemampuan, pengelompokkan siswa berdasarkan nilai yang diperoleh, penyajian data dan penarikan kesimpulan. Hasil penelitian ini menunjukkan bahwa 2,13% siswa berada dalam kategori sangat baik, 4,26% siswa berada dalam kategori baik, 4,26% siswa berada dalam kategori cukup, dan 89,36% siswa berada dalam kategori kurang. Dengan demikian kemampuan menghitung integral tak tentu dan tentu dari fungsi aljabar sederhana serta penerapannya dalam menghitung luas daerah di bawah kurva siswa kelas XII IPS SMA Syaichona Cholil Samarinda Tahun Ajaran 2017/2018 adalah kurang

Investigation of structural, electronic and magnetic properties of breathing metal-organic framework MIL-47(Mn): A first principles approach

The structural, electronic and magnetic properties of the MIL-47(Mn) metal-organic framework are investigated using first principles calculations. We find that the large-pore structure is the ground state of this material. We show that upon transition from the large-pore to the narrow-pore structure, the magnetic ground-state configuration changes from antiferromagnetic to ferromagnetic, consistent with the computed values of the intra-chain coupling constant. Furthermore, the antiferromagnetic and ferromagnetic configuration phases have intrinsically different electronic behavior: the former is semiconducting, the latter is a metal or half-metal. The change of electronic properties during breathing posits MIL-47(Mn) as a good candidate for sensing and other applications. Our calculated electronic band structure for MIL-47(Mn) presents a combination of flat dispersionless and strongly dispersive regions in the valence and conduction bands, indicative of quasi-1D electronic behavior. The spin coupling constants are obtained by mapping the total energies onto a spin Hamiltonian. The inter-chain coupling is found to be at least one order of magnitude smaller than the intra-chain coupling for both large and narrow pores. Interestingly, the intra-chain coupling changes sign and becomes five times stronger going from the large pore to the narrow pore structure. As such MIL-47(Mn) could provide unique opportunities for tunable low-dimensional magnetism in transition metal oxide systems