Gallbladder cancer is the most common tumor of the biliary tract and it is associated with a poor prognosis.Unexpected gallbladder cancer is a cancer incidentally discovered,as a surprise,at the histological examinati...Gallbladder cancer is the most common tumor of the biliary tract and it is associated with a poor prognosis.Unexpected gallbladder cancer is a cancer incidentally discovered,as a surprise,at the histological examination after cholecystectomy for gallstones or other indications.It is a potentially curable disease,with an intermediate or good prognosis in most cases.An adequate surgical strategy is mandatory to improve the prognosis and an adjunctive radical resection may be required depending on the depth of invasion.If the cancer discovered after cholecystectomy is a pTis or a pT1a,a second surgical procedure is not mandatory.In the other cases(pT1b,pT2 and pT3 cancer) a re-resection(4b + 5 liver segmentectomy,lymphadenectomy and port-sites excision in some cases) is required to obtain a radical excision of the tumor and an accurate disease staging.The operative specimens of re-resection should be examined by the pathologist to find any "residual" tumor.The "residual disease" is the most important prognostic factor,significantly reducing median disease-free survival and disease-specific survival.The other factors include depth of parietal invasion,metastatic nodal disease,surgical margin status,cholecystectomy for acute cholecystitis,histological differentiation,lymphatic,vascular and perineural invasion and overall TNM-stage.展开更多
Structural and geomorphological analysis of the Martian surface in the visible spectral range using the NASA/Viking images in the 90’s,complemented by experimental modelling(Mège and Masson,1996a;Mège et al...Structural and geomorphological analysis of the Martian surface in the visible spectral range using the NASA/Viking images in the 90’s,complemented by experimental modelling(Mège and Masson,1996a;Mège et al.,2003)suggested that the Valles Marineris trough(chasma)system is aligned with a mafic dyke swarm,named the Syria Planum Dyke Swarm.Cross-cutting relationships and展开更多
Lithium plays an increasingly important role in scientific and industrial processes, and it is extremely important to extract lithium from a high Mg^(2+)/Li^(+) mass ratio brine or to recover lithium from the leachate...Lithium plays an increasingly important role in scientific and industrial processes, and it is extremely important to extract lithium from a high Mg^(2+)/Li^(+) mass ratio brine or to recover lithium from the leachate of spent lithiumion batteries. Conventional wisdom shows that Li^(+) with low valence states has a much weaker adsorption(and absorption energy) with graphene than multivalent ions such as Mg^(2+). Here, we show the selective adsorption of Li^(+) in thermally reduced graphene oxide(rGO) membranes over other metal ions such as Mg^(2+), Co^(2+), Mn^(2+),Ni^(2+), or Fe^(2+). Interestingly, the adsorption strength of Li^(+) reaches up to 5 times the adsorption strength of Mg^(2+),and the mass ratio of a mixed Mg^(2+)/Li^(+) solution at a very high value of 500 : 1 can be effectively reduced to 0.7 : 1 within only six experimental treatment cycles, demonstrating the excellent applicability of the rGO membranes in the Mg^(2+)/Li^(+) separation. A theoretical analysis indicates that this unexpected selectivity is attributed to the competition between cation–π interaction and steric exclusion when hydrated cations enter the confined space of the rGO membranes.展开更多
BACKGROUND The term sudden unexpected infant death(SUID)is not always properly invoked.It refers to a broad range of conditions that sometimes defy classification.There is not only a strong emotional impact on the fam...BACKGROUND The term sudden unexpected infant death(SUID)is not always properly invoked.It refers to a broad range of conditions that sometimes defy classification.There is not only a strong emotional impact on the family,but such cases are also quite complex.Underlying causes may be multiple,not always readily apparent,and have potential repercussions,especially in terms of forensics.CASE SUMMARY A 5-month-old male baby was pronounced dead following acute lung failure and cardiopulmonary arrest.The parents had immediately rushed their child to the hospital,stating the baby was found prone and not breathing.Total-body postmortem computed tomography(PMCT)was performed,revealing a hypodense material of indeterminate nature within the main airways and areas of ground-glass parenchymal change.At autopsy,the respiratory tract mucosa appeared edematous and was coated with a whitish stringy material.There was widespread airspace reduction due to parenchymal collapse.Alveolar sacs and bronchial openings contained abundant amorphous material admixed with white blood cells.Immunohistochemical studies were performed,targeting CD15,CD68,and alpha-lactalbumin.Ultimately,the focus was on alpha-lactalbumin(milk protein),which showed marked immunopositivity within alveolar spaces.Cytoplasmic staining of macrophages was also particularly prominent.CONCLUSION Postmortem investigations are thus essential to identify causes of death and surrounding circumstances.PMCT is a useful tool in this setting,given the frequent dearth of autopsy findings and ambiguity as to cause of death in SUID cases.These findings,later confirmed by immunohistochemical investigations,were indicative of active pneumonia due to aspirated milk.The present account illustrates the importance a broad diagnostic approach to SUID in cases of forensic concern.PMCT is a very valuable aid in cases of forensic interest,as it can provide useful information in all those situations in which the cause of death is uncertain or there are no suggestive dynamics or lesions.展开更多
By analyzing disposal status of unexpected environmental incidents by government,public and enterprise,and combining the characteristics of unexpected environmental incidents,specific measures of responding to unexpec...By analyzing disposal status of unexpected environmental incidents by government,public and enterprise,and combining the characteristics of unexpected environmental incidents,specific measures of responding to unexpected environmental incidents are proposed from the aspects of perfecting guarantee system of emergency nomocracy,enhancing information disclosure,encouraging public participation,enhancing the construction of emergency response capability,and enhancing post-event management,to improve the ability of defending environmental risk.展开更多
An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed b...An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed.展开更多
Objective: To study whether the unexpected poor ovarian responders optimization of uterine receptivity with a flexible controlled ovarian hyper stimulation protocol based on the Biophysical Profile of the Uterus, has ...Objective: To study whether the unexpected poor ovarian responders optimization of uterine receptivity with a flexible controlled ovarian hyper stimulation protocol based on the Biophysical Profile of the Uterus, has an impact on their reproductive performance. Design: Observational Prospective study. Setting(s): i) General hospital-IVF and Infertility Centre;ii) University hospital. Patient(s): 44 normogonadotrophic young women (26 - 38 yrs) with previous “unexpected” poor ovarian response underwent IVF/ICSI treatment on a protocol based on the Biophysical Profile of their uterus (Group A). The same patients were used as controls in a preceded IVF cycle on the conventional stimulation protocol. Intervention(s): None. Main outcome measure(s): Pregnancy, miscarriage and home take baby rates, amount and duration of gonadotropins required, number and quality of embryos resulted, Biophysical Profile of the Uterus score. Result(s). Treatment in Group A in comparison to Group B resulted in significantly larger number of eggs retrieved per patient, and improved fertilization rates and higher number of embryos/ET (p = 0.011, 0.010 and 0.034 respectively). Group A also demonstrated a trend for higher rates of clinical pregnancy (29.5% v.s. 15.9%), viable stage pregnancies ≥ 24 weeks (33.3% v.s. 20%) and home take babies (26.6% v.s. 16%). The amount of gonadotropins used per patient (IU) was similar in the two groups (p = 0.264). Cancellation, implantation and miscarriage rates as well as embryos quality, although superior in the treatment Group A, showed no significant difference. The number of pregnancies achieved in Group A, were directly related with the score in the Biophysical Profile of the Uterus 12 point scale. Conclusion(s): Unexpected Poor Ovarian Responders on the flexible IVF/ICSI protocol (Group A), adjusting the management according to the Biophysical Profile of their uterus (duration of stimulation, day of HCG and day of embryo transfer), had a significantly better performance in comparison to the Group B managed on the conventional protocol in this difficult to manage and so far, rather understudied population.展开更多
一、目标导航(一)重点单词及短语unexpected,backpack,oversleep,give…a lift,by the time(that)(二)重点句型(1)By the time I got up,my brother had already gotten in the shower.(2)When I got home,I realized I had l...一、目标导航(一)重点单词及短语unexpected,backpack,oversleep,give…a lift,by the time(that)(二)重点句型(1)By the time I got up,my brother had already gotten in the shower.(2)When I got home,I realized I had left my keys in the backpack.(3)When I woke up it was already 8:00 a.m.!(4)Before I got to the bus stop,the bus had already left.展开更多
There is a wide range of anatomical variations in the pulmonary vessels. Some of these variations may cause surgical morbidity during general thoracic surgery. We intended to perform a left upper lobectomy for a 73-ye...There is a wide range of anatomical variations in the pulmonary vessels. Some of these variations may cause surgical morbidity during general thoracic surgery. We intended to perform a left upper lobectomy for a 73-year-old male with suspected left lung cancer (lt.U, S<sup>3</sup>, 20 × 20 mm, P0, E0, D0, PM0, N0, T1aN0M0, c-stage IA). Preoperatively, we did not recognize the existence of the common trunk of the left pulmonary vein. After the open thoracotomy, due to a severe intrathoracic adhesion, we omitted releasing the adhesion of the lower lobe. We did not exactly confirm the location of the inferior pulmonary vein (IPV). After cutting the interlobular pulmonary arterial branchies, we resected the superior pulmonary vein (SPV) using auto sutures. After division of the lung parenchyma and incomplete fissures using auto sutures, we intended to resect the upper bronchus. However, we could not find an IPV at the normal IPV site. A thin IPV was found to be returned to the peripheral site of the resected SPV. The SPV and IPV formed a common trunk at the normal site of the SPV. Although we considered reconstructing the resected common trunk, we finally made a decision of performing an incidental pneumonectomy in order to prevent any postoperative complications on the reconstruction of the IPV such as thrombus occlusion at the anastomosis site and venous return congestion. Retrospectively, we confirmed the preoperative images of the computed tomographic scanning, which showed a narrow IPV that returned to the peripheral site of the SPV. It is important to confirm both accurate locations of the SPV and IPV when performing a lobectomy.展开更多
Once upon a time,there was a boy with short hair and a round belly[肚子].Now he hates adventures[冒险]and feels a strange kind of fear to the unknown future.That’s me and I call myself Hobbit Boy.A hobbit is a creatu...Once upon a time,there was a boy with short hair and a round belly[肚子].Now he hates adventures[冒险]and feels a strange kind of fear to the unknown future.That’s me and I call myself Hobbit Boy.A hobbit is a creature[生物]from England writer J.R.R.Tolkien’s stories.They have short bodies with unusually big feet that have long curly hair.They live in comfortable Hobbit Holes,never do anything challenging or exciting—but展开更多
"IF you love him, send him to New York, for it's heaven. If you hate him, send him to New York, for it's hell." These are lines from A Beijing Native in New York, a popular Chinese TV series from the early 1990s...."IF you love him, send him to New York, for it's heaven. If you hate him, send him to New York, for it's hell." These are lines from A Beijing Native in New York, a popular Chinese TV series from the early 1990s. Until that point, going abroad had only been an option for China's elite. Once this changed and the trend gradu- ally swept across the country, regular Chinese people began harboring an "American dream" in their hearts.展开更多
IN the spacious, bright and slightly noisy sewing section of Tanzania Tooku Garments, Shraban Kitwana works fast at his desk, quickly unhooking two pieces of a pair of trousers from the dispatching machine and partly ...IN the spacious, bright and slightly noisy sewing section of Tanzania Tooku Garments, Shraban Kitwana works fast at his desk, quickly unhooking two pieces of a pair of trousers from the dispatching machine and partly stitching them together on his sewing machine in just 10 seconds.展开更多
Multi-agent reinforcement learning is difficult to apply in practice,partially because of the gap between simulated and real-world scenarios.One reason for the gap is that simulated systems always assume that agents c...Multi-agent reinforcement learning is difficult to apply in practice,partially because of the gap between simulated and real-world scenarios.One reason for the gap is that simulated systems always assume that agents can work normally all the time,while in practice,one or more agents may unexpectedly“crash”during the coordination process due to inevitable hardware or software failures.Such crashes destroy the cooperation among agents and lead to performance degradation.In this work,we present a formal conceptualization of a cooperative multi-agent reinforcement learning system with unexpected crashes.To enhance the robustness of the system to crashes,we propose a coach-assisted multi-agent reinforcement learning framework that introduces a virtual coach agent to adjust the crash rate during training.We have designed three coaching strategies(fixed crash rate,curriculum learning,and adaptive crash rate)and a re-sampling strategy for our coach agent.To our knowledge,this work is the first to study unexpected crashes in a multi-agent system.Extensive experiments on grid-world and StarCraft II micromanagement tasks demonstrate the efficacy of the adaptive strategy compared with the fixed crash rate strategy and curriculum learning strategy.The ablation study further illustrates the effectiveness of our re-sampling strategy.展开更多
The unexpected emergent discharge of high- arsenic wastewater into water environments results in significantly increased levels of arsenic in water; however, the species distribution of arsenic in sediments has never ...The unexpected emergent discharge of high- arsenic wastewater into water environments results in significantly increased levels of arsenic in water; however, the species distribution of arsenic in sediments has never been reported before for such cases. This study focuses on an As pollution accident in the Dasha River, and uses sequential extraction procedures with deionized water, l mol-L-1 MgC12 at pH = 8, 1 mol.L-1 NaH2PO4 at pH = 5, and 1 mol. L-1 HC1 to investigate four binding phases of arsenic (i.e., water soluble, ion-exchangeable, strongly- bound, and precipitates) in sediments at different layers in different cross-sections along the fiver. The average ratio of arsenite (As(III)) to arsenate (As(V)) was found to decrease from 0.74:1 in fiver water to 0.48:1 in sediment, owing to its higher affinity toward As(V) than As(III). The content of arsenic in the sediments was relatively low and the maximum content was observed to be 36.3 mg-kg1 for As(IID and 97.5 mg.kg1 for As(V). As(III) and As(V) showed different binding phases in sediments, and the average fractions of these four species were determined to be 0.09, 0.11, 0.17, and 0.63 for As(III) and 0.03, 0.14, 0.63, and 0.20 for As(V), respectively. For all the sediment samples, the content of arsenic showed no relationship with the characteristics of the sediments such as the particle diameter, the content of organic carbon, Fe, and Mn, although a negative correlation with particle diameter was observed for the sediments in the uppermost 2-cm layer. The unexpected emergent As incident results in the high content of total arsenic in the surface sediment, which may be potential secondary source to the elevated As levels in surface water.展开更多
Short-duration gamma-ray bursts (SGRBs) are mysterious gamma-ray flashes with durations less than two seconds, which occur at the cosmological distances. Some of them usually not only have very tenuous medium gases an...Short-duration gamma-ray bursts (SGRBs) are mysterious gamma-ray flashes with durations less than two seconds, which occur at the cosmological distances. Some of them usually not only have very tenuous medium gases and old host galaxies but also are in the outskirts of the galaxies, suggesting an origin of binary neutron star (NS) mergers (1)This origin was confirmed undoubtedly thanks to the discoveries of a gravitational wave event namedGW170817 and its electromagnetic counterparts (an SGRB, a multiwavelengthkilo-nova, and a broadband afterglow) [2].展开更多
Scientific knowledge often advances by extending established theories and research methods into new areas.An Earth Science example is the extension of geological mapping to previously unvisited areas.If this were the ...Scientific knowledge often advances by extending established theories and research methods into new areas.An Earth Science example is the extension of geological mapping to previously unvisited areas.If this were the only way to advance,unexpected discoveries would become rarer as time goes on and geologists map more and more of the Earth’s surface.展开更多
With the support by the National Natural Science Foundation of China and Chinese Academy of Sciences,the research group led by Prof.Gao Yi(高嶷)at the CAS Key Laboratory of Interfacial Physics and Technology,Shanghai ...With the support by the National Natural Science Foundation of China and Chinese Academy of Sciences,the research group led by Prof.Gao Yi(高嶷)at the CAS Key Laboratory of Interfacial Physics and Technology,Shanghai Institute of Applied Physics,Chinese Academy of Sciences,disclosed the unexpected shape evolution of metal nanoparticles by water vapor,which was published in Nano Letters(2016,展开更多
文摘Gallbladder cancer is the most common tumor of the biliary tract and it is associated with a poor prognosis.Unexpected gallbladder cancer is a cancer incidentally discovered,as a surprise,at the histological examination after cholecystectomy for gallstones or other indications.It is a potentially curable disease,with an intermediate or good prognosis in most cases.An adequate surgical strategy is mandatory to improve the prognosis and an adjunctive radical resection may be required depending on the depth of invasion.If the cancer discovered after cholecystectomy is a pTis or a pT1a,a second surgical procedure is not mandatory.In the other cases(pT1b,pT2 and pT3 cancer) a re-resection(4b + 5 liver segmentectomy,lymphadenectomy and port-sites excision in some cases) is required to obtain a radical excision of the tumor and an accurate disease staging.The operative specimens of re-resection should be examined by the pathologist to find any "residual" tumor.The "residual disease" is the most important prognostic factor,significantly reducing median disease-free survival and disease-specific survival.The other factors include depth of parietal invasion,metastatic nodal disease,surgical margin status,cholecystectomy for acute cholecystitis,histological differentiation,lymphatic,vascular and perineural invasion and overall TNM-stage.
文摘Structural and geomorphological analysis of the Martian surface in the visible spectral range using the NASA/Viking images in the 90’s,complemented by experimental modelling(Mège and Masson,1996a;Mège et al.,2003)suggested that the Valles Marineris trough(chasma)system is aligned with a mafic dyke swarm,named the Syria Planum Dyke Swarm.Cross-cutting relationships and
基金Supported by the Fundamental Research Funds for the Central Universitiesthe National Natural Science Foundation of China(Grant Nos. 11974366, 11675246, 12074341, U1832170, and U1832150)+2 种基金the Key Research Program of Chinese Academy of Sciences(Grant No. QYZDJ-SSW-SLH053)the Computer Network Information Center of the Chinese Academy of Sciencesthe Shanghai Supercomputer Center of China。
文摘Lithium plays an increasingly important role in scientific and industrial processes, and it is extremely important to extract lithium from a high Mg^(2+)/Li^(+) mass ratio brine or to recover lithium from the leachate of spent lithiumion batteries. Conventional wisdom shows that Li^(+) with low valence states has a much weaker adsorption(and absorption energy) with graphene than multivalent ions such as Mg^(2+). Here, we show the selective adsorption of Li^(+) in thermally reduced graphene oxide(rGO) membranes over other metal ions such as Mg^(2+), Co^(2+), Mn^(2+),Ni^(2+), or Fe^(2+). Interestingly, the adsorption strength of Li^(+) reaches up to 5 times the adsorption strength of Mg^(2+),and the mass ratio of a mixed Mg^(2+)/Li^(+) solution at a very high value of 500 : 1 can be effectively reduced to 0.7 : 1 within only six experimental treatment cycles, demonstrating the excellent applicability of the rGO membranes in the Mg^(2+)/Li^(+) separation. A theoretical analysis indicates that this unexpected selectivity is attributed to the competition between cation–π interaction and steric exclusion when hydrated cations enter the confined space of the rGO membranes.
文摘BACKGROUND The term sudden unexpected infant death(SUID)is not always properly invoked.It refers to a broad range of conditions that sometimes defy classification.There is not only a strong emotional impact on the family,but such cases are also quite complex.Underlying causes may be multiple,not always readily apparent,and have potential repercussions,especially in terms of forensics.CASE SUMMARY A 5-month-old male baby was pronounced dead following acute lung failure and cardiopulmonary arrest.The parents had immediately rushed their child to the hospital,stating the baby was found prone and not breathing.Total-body postmortem computed tomography(PMCT)was performed,revealing a hypodense material of indeterminate nature within the main airways and areas of ground-glass parenchymal change.At autopsy,the respiratory tract mucosa appeared edematous and was coated with a whitish stringy material.There was widespread airspace reduction due to parenchymal collapse.Alveolar sacs and bronchial openings contained abundant amorphous material admixed with white blood cells.Immunohistochemical studies were performed,targeting CD15,CD68,and alpha-lactalbumin.Ultimately,the focus was on alpha-lactalbumin(milk protein),which showed marked immunopositivity within alveolar spaces.Cytoplasmic staining of macrophages was also particularly prominent.CONCLUSION Postmortem investigations are thus essential to identify causes of death and surrounding circumstances.PMCT is a useful tool in this setting,given the frequent dearth of autopsy findings and ambiguity as to cause of death in SUID cases.These findings,later confirmed by immunohistochemical investigations,were indicative of active pneumonia due to aspirated milk.The present account illustrates the importance a broad diagnostic approach to SUID in cases of forensic concern.PMCT is a very valuable aid in cases of forensic interest,as it can provide useful information in all those situations in which the cause of death is uncertain or there are no suggestive dynamics or lesions.
文摘By analyzing disposal status of unexpected environmental incidents by government,public and enterprise,and combining the characteristics of unexpected environmental incidents,specific measures of responding to unexpected environmental incidents are proposed from the aspects of perfecting guarantee system of emergency nomocracy,enhancing information disclosure,encouraging public participation,enhancing the construction of emergency response capability,and enhancing post-event management,to improve the ability of defending environmental risk.
文摘An unexpected compound, hydroperoxide (4) formed from (3), the exo-cycloaddition product, which was synthesized through the Lewis acid catlyzed intramolecular Diels-Alder (IMDA) reaction. Its structure was confirmed by spectra and X-Ray diffraction analysis, An 1O2oxidation mechanism was proposed.
文摘Objective: To study whether the unexpected poor ovarian responders optimization of uterine receptivity with a flexible controlled ovarian hyper stimulation protocol based on the Biophysical Profile of the Uterus, has an impact on their reproductive performance. Design: Observational Prospective study. Setting(s): i) General hospital-IVF and Infertility Centre;ii) University hospital. Patient(s): 44 normogonadotrophic young women (26 - 38 yrs) with previous “unexpected” poor ovarian response underwent IVF/ICSI treatment on a protocol based on the Biophysical Profile of their uterus (Group A). The same patients were used as controls in a preceded IVF cycle on the conventional stimulation protocol. Intervention(s): None. Main outcome measure(s): Pregnancy, miscarriage and home take baby rates, amount and duration of gonadotropins required, number and quality of embryos resulted, Biophysical Profile of the Uterus score. Result(s). Treatment in Group A in comparison to Group B resulted in significantly larger number of eggs retrieved per patient, and improved fertilization rates and higher number of embryos/ET (p = 0.011, 0.010 and 0.034 respectively). Group A also demonstrated a trend for higher rates of clinical pregnancy (29.5% v.s. 15.9%), viable stage pregnancies ≥ 24 weeks (33.3% v.s. 20%) and home take babies (26.6% v.s. 16%). The amount of gonadotropins used per patient (IU) was similar in the two groups (p = 0.264). Cancellation, implantation and miscarriage rates as well as embryos quality, although superior in the treatment Group A, showed no significant difference. The number of pregnancies achieved in Group A, were directly related with the score in the Biophysical Profile of the Uterus 12 point scale. Conclusion(s): Unexpected Poor Ovarian Responders on the flexible IVF/ICSI protocol (Group A), adjusting the management according to the Biophysical Profile of their uterus (duration of stimulation, day of HCG and day of embryo transfer), had a significantly better performance in comparison to the Group B managed on the conventional protocol in this difficult to manage and so far, rather understudied population.
文摘一、目标导航(一)重点单词及短语unexpected,backpack,oversleep,give…a lift,by the time(that)(二)重点句型(1)By the time I got up,my brother had already gotten in the shower.(2)When I got home,I realized I had left my keys in the backpack.(3)When I woke up it was already 8:00 a.m.!(4)Before I got to the bus stop,the bus had already left.
文摘There is a wide range of anatomical variations in the pulmonary vessels. Some of these variations may cause surgical morbidity during general thoracic surgery. We intended to perform a left upper lobectomy for a 73-year-old male with suspected left lung cancer (lt.U, S<sup>3</sup>, 20 × 20 mm, P0, E0, D0, PM0, N0, T1aN0M0, c-stage IA). Preoperatively, we did not recognize the existence of the common trunk of the left pulmonary vein. After the open thoracotomy, due to a severe intrathoracic adhesion, we omitted releasing the adhesion of the lower lobe. We did not exactly confirm the location of the inferior pulmonary vein (IPV). After cutting the interlobular pulmonary arterial branchies, we resected the superior pulmonary vein (SPV) using auto sutures. After division of the lung parenchyma and incomplete fissures using auto sutures, we intended to resect the upper bronchus. However, we could not find an IPV at the normal IPV site. A thin IPV was found to be returned to the peripheral site of the resected SPV. The SPV and IPV formed a common trunk at the normal site of the SPV. Although we considered reconstructing the resected common trunk, we finally made a decision of performing an incidental pneumonectomy in order to prevent any postoperative complications on the reconstruction of the IPV such as thrombus occlusion at the anastomosis site and venous return congestion. Retrospectively, we confirmed the preoperative images of the computed tomographic scanning, which showed a narrow IPV that returned to the peripheral site of the SPV. It is important to confirm both accurate locations of the SPV and IPV when performing a lobectomy.
文摘Once upon a time,there was a boy with short hair and a round belly[肚子].Now he hates adventures[冒险]and feels a strange kind of fear to the unknown future.That’s me and I call myself Hobbit Boy.A hobbit is a creature[生物]from England writer J.R.R.Tolkien’s stories.They have short bodies with unusually big feet that have long curly hair.They live in comfortable Hobbit Holes,never do anything challenging or exciting—but
文摘"IF you love him, send him to New York, for it's heaven. If you hate him, send him to New York, for it's hell." These are lines from A Beijing Native in New York, a popular Chinese TV series from the early 1990s. Until that point, going abroad had only been an option for China's elite. Once this changed and the trend gradu- ally swept across the country, regular Chinese people began harboring an "American dream" in their hearts.
文摘IN the spacious, bright and slightly noisy sewing section of Tanzania Tooku Garments, Shraban Kitwana works fast at his desk, quickly unhooking two pieces of a pair of trousers from the dispatching machine and partly stitching them together on his sewing machine in just 10 seconds.
基金Project supported by the National Natural Science Foundation of China(No.61836011)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2018497)the GPU cluster built by the MCC Lab of Information Science and Technology Institution,USTC,China。
文摘Multi-agent reinforcement learning is difficult to apply in practice,partially because of the gap between simulated and real-world scenarios.One reason for the gap is that simulated systems always assume that agents can work normally all the time,while in practice,one or more agents may unexpectedly“crash”during the coordination process due to inevitable hardware or software failures.Such crashes destroy the cooperation among agents and lead to performance degradation.In this work,we present a formal conceptualization of a cooperative multi-agent reinforcement learning system with unexpected crashes.To enhance the robustness of the system to crashes,we propose a coach-assisted multi-agent reinforcement learning framework that introduces a virtual coach agent to adjust the crash rate during training.We have designed three coaching strategies(fixed crash rate,curriculum learning,and adaptive crash rate)and a re-sampling strategy for our coach agent.To our knowledge,this work is the first to study unexpected crashes in a multi-agent system.Extensive experiments on grid-world and StarCraft II micromanagement tasks demonstrate the efficacy of the adaptive strategy compared with the fixed crash rate strategy and curriculum learning strategy.The ablation study further illustrates the effectiveness of our re-sampling strategy.
文摘The unexpected emergent discharge of high- arsenic wastewater into water environments results in significantly increased levels of arsenic in water; however, the species distribution of arsenic in sediments has never been reported before for such cases. This study focuses on an As pollution accident in the Dasha River, and uses sequential extraction procedures with deionized water, l mol-L-1 MgC12 at pH = 8, 1 mol.L-1 NaH2PO4 at pH = 5, and 1 mol. L-1 HC1 to investigate four binding phases of arsenic (i.e., water soluble, ion-exchangeable, strongly- bound, and precipitates) in sediments at different layers in different cross-sections along the fiver. The average ratio of arsenite (As(III)) to arsenate (As(V)) was found to decrease from 0.74:1 in fiver water to 0.48:1 in sediment, owing to its higher affinity toward As(V) than As(III). The content of arsenic in the sediments was relatively low and the maximum content was observed to be 36.3 mg-kg1 for As(IID and 97.5 mg.kg1 for As(V). As(III) and As(V) showed different binding phases in sediments, and the average fractions of these four species were determined to be 0.09, 0.11, 0.17, and 0.63 for As(III) and 0.03, 0.14, 0.63, and 0.20 for As(V), respectively. For all the sediment samples, the content of arsenic showed no relationship with the characteristics of the sediments such as the particle diameter, the content of organic carbon, Fe, and Mn, although a negative correlation with particle diameter was observed for the sediments in the uppermost 2-cm layer. The unexpected emergent As incident results in the high content of total arsenic in the surface sediment, which may be potential secondary source to the elevated As levels in surface water.
文摘Short-duration gamma-ray bursts (SGRBs) are mysterious gamma-ray flashes with durations less than two seconds, which occur at the cosmological distances. Some of them usually not only have very tenuous medium gases and old host galaxies but also are in the outskirts of the galaxies, suggesting an origin of binary neutron star (NS) mergers (1)This origin was confirmed undoubtedly thanks to the discoveries of a gravitational wave event namedGW170817 and its electromagnetic counterparts (an SGRB, a multiwavelengthkilo-nova, and a broadband afterglow) [2].
文摘Scientific knowledge often advances by extending established theories and research methods into new areas.An Earth Science example is the extension of geological mapping to previously unvisited areas.If this were the only way to advance,unexpected discoveries would become rarer as time goes on and geologists map more and more of the Earth’s surface.
文摘With the support by the National Natural Science Foundation of China and Chinese Academy of Sciences,the research group led by Prof.Gao Yi(高嶷)at the CAS Key Laboratory of Interfacial Physics and Technology,Shanghai Institute of Applied Physics,Chinese Academy of Sciences,disclosed the unexpected shape evolution of metal nanoparticles by water vapor,which was published in Nano Letters(2016,