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The giant Yulong porphyry Cu Mo deposit was formed in postsubduction setting in eastern Tibet. Origin of the ore-related Yulong intrusion remains a matter of debate. This study presents new whole-rock major and trace element geochemistry, in-situ apatite Sr Nd and zircon Hf O isotopes, and mineralogical chemistry of the Yulong intrusion. Least-altered samples from the Yulong intrusion have high SiO 2 (66.3–69.5 wt%) and Al 2 O 3 (14.9–15.5 wt%) contents, high La/Yb (36.4–68.0) and Sr/Y (46.0–76.3) ratios, and low MgO (0.63–1.24 wt%) and Cr (<30 ppm) contents, similar to adakitic rocks deriving from thick juvenile lower crust. They are enriched in large ion lithophile elements (LILEs) and depletion in high field strength elements (HFSEs), and show listric REE patterns. In-situ apatite Sr Nd isotopes show limited variations ((87Sr/86Sr) i = 0.7060–0.7068, εNd(t) = −4.8–0.2), which plot between Paleo-Tethys ocean-related arc magmas and the ancient crust in eastern Tibet. Zircon grains from this study and published studies have mostly positive yet variable εHf(t) values (−20.6 to +12.2) and young Hf model ages that overlap those of the Paleo-Tethys ocean-related arc magmas. The above Sr-Nd-Hf isotopes, together with the elevated zircon δ18O values (6.4 to 9.3‰) and arc-like trace element patterns, collectively suggest that the Yulong intrusion may have originated from partial melting of juvenile lower arc crust related to the subduction of the Paleo-Tethys ocean, with incorporation of a small amount of ancient crustal materials. Two generations of amphibole were recognized at Yulong. Their compositions are used to calculate crystallization depths, magmatic oxidation states, and water contents. The caculated results show that the early-stage euhedral high-Al (5.87–8.51 wt%) amphibole phenocrysts may have crystallized in the underlying magma chamber (7.1–12.5 km in depth), whereas the late-stage xenomorphic low-Al (3.47–4.87 wt%) amphibole grains may have crystallized in the porphyritic stock (4.0–5.6 km). Magmatic water contents decrease from early- (3.5–4.6 wt%) to late-stage (2.8–3.5 wt%) amphibole, which is interpreted to indicate fluid exsolution from the magma chamber during emplacement of the Yulong intrusion. Caculated oxidation states increase from early- (ΔNNO = 0.6–1.5) to late-stage (ΔNNO = 1.9–2.3) amphibole. Plagioclase phenocrysts show periodic or reverse core-to-rim zonation of An contents (range up to 25 mol%), which are coupled by FeO contents, probably suggesting magma recharge events. Collectively, we propose that the magma chamber beneath Yulong was recharged by a less evolved magma, and was saturated in fluids to produce intensive alteration and mineralization. The relatively high oxidation states allow the metals to be enriched in the evolving magma, and to be deposited in the hydrothermal alteration stage. Unlabelled Image • The Yulong intrusion derived from a juvenile lower arc crust with incorporation of a small amount of ancient crustal materials • The juvenile lower arc crust was formed during subduction of the Paleo-Tethys Ocean • The magma chamber was recharged by a less evolved magma, and was saturated in fluids during emplacement of the Yulong intrusion [ABSTRACT FROM AUTHOR]

Objective: To improve clinicians' ability of diagnosing testicular torsion., Methods: We reviewed the data of a case of testicular torsion that resulted in necrosis because of delayed presentation and repeated misdiagnosis, and analyzed its anatomic features, clinical manifestations, ultrasound results, the causes of misdiagnosis and relevant literature., Results: The patient presented 5 hours after the onset of symptoms, complaining of severe paroxysmal pain in the lower left abdomen, accompanied with nausea and vomiting, and was twice misdiagnosed as having enterospasm or ureteral calculus at two different hospitals. Fifteen hours later, surgical exploration revealed an about 900-degree testicular torsion in the spermatic cord, which necessitated orchiectomy for non viability of the testis. Postoperative pathological examination confirmed testicular necrosis and diffused hemorrhage in the testis and epididymis., Conclusion: Timely presentation, correct diagnosis and proper treatment are keys to saving the affected testis. Color Doppler ultrasound is an ideal option for the definite diagnosis of acute scrotal diseases, and it offers a valuable guidance for related surgery as well.