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1.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38728703

ABSTRACT

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

2.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36493436

ABSTRACT

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.


Subject(s)
Electricity , Electrons
3.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36493447

ABSTRACT

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.


Subject(s)
Cell Nucleus , Photons
4.
Br J Surg ; 107(10): 1334-1343, 2020 09.
Article in English | MEDLINE | ID: mdl-32452559

ABSTRACT

BACKGROUND: In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection. METHODS: Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted. RESULTS: Data from 937 patients were available for evaluation. The overall 5-year disease-free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5-year disease-free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5-year disease-free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five-year disease-free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic. CONCLUSION: Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.


ANTECEDENTES: En el cáncer de vesícula biliar, la ubicación del tumor subdivide el estadio T2 en tumores con invasión del lado peritoneal y del lado del hígado (T2a y T2b). Para los tumores que invaden el lado peritoneal (T2a) se sugiere que se puede obviar la resección hepática sin que ello comprometa el pronóstico. Sin embargo, este argumento no ha sido validado. El estudio tuvo como objetivo investigar el valor pronóstico de la localización del tumor en el cáncer de vesícula biliar T2 y establecer la extensión adecuada de la resección quirúrgica. MÉTODOS: Se recogieron los datos clínicos de pacientes que se sometieron a cirugía por cáncer de vesícula biliar en 14 hospitales de Corea, Japón, Chile y Estados Unidos. Se realizaron análisis de la supervivencia y de los factores de riesgo. RESULTADOS: Se dispuso de datos de 937 pacientes para ser evaluados. La tasa de supervivencia global libre de enfermedad a los 5 años fue del 70,6%, y las de T2a y T2b del 74,5% y 65,5% (P = 0,028). Con respecto a la resección hepática, la colecistectomía extendida presentó una tasa mejor de supervivencia libre de enfermedad a los 5 años que la colecistectomía simple (73,0% versus 61,5%, P = 0,012). La tasa de supervivencia libre de enfermedad a los 5 años fue marginalmente mejor para la colecistectomía extendida que para la colecistectomía simple tanto en T2a (76,5% versus 66,1%, P = 0,094) como en T2b (68,2% versus 56,2%, P = 0,084). Las tasas de supervivencia libre de enfermedad a los 5 años no fueron diferentes entre la resección hepática en cuña y la segmentectomía S4b+S5 (74,1% versus 71,5%, P = 0,720). En el análisis multivariable, los factores de riesgo independientes para la recidiva fueron la presencia de síntomas (cociente de riesgos instantáneos, hazard ratio, HR 1,52, P = 0,002), la resección R1 (HR 1,96, P = 0,004) y el estadio N1/N2 (N1 HR 3,40, P < 0,001; N2 HR 9,56, P < 0,001). El 70,8% de las recidivas eran metastásicas. CONCLUSIÓN: La localización del tumor no fue un factor pronóstico independiente en el cáncer de vesícula biliar T2. La colecistectomía extendida fue marginalmente superior que la colecistectomía simple. La cirugía radical debe incluir una resección hepática y una linfadenectomía adecuada.


Subject(s)
Gallbladder Neoplasms/mortality , Gallbladder Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Chile , Cholecystectomy , Disease-Free Survival , Female , Gallbladder Neoplasms/pathology , Hepatectomy , Humans , Japan , Lymph Node Excision , Male , Middle Aged , Neoplasm Metastasis , Neoplasm Recurrence, Local , Prognosis , Republic of Korea , Risk Factors , United States
5.
Phys Rev Lett ; 124(11): 111301, 2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32242731

ABSTRACT

We report constraints on the dark photon effective kinetic mixing parameter (κ) with data taken from two p-type point-contact germanium detectors of the CDEX-10 experiment at the China Jinping Underground Laboratory. The 90% confidence level upper limits on κ of solar dark photon from 205.4 kg-day exposure are derived, probing new parameter space with masses (m_{V}) from 10 to 300 eV/c^{2} in direct detection experiments. Considering dark photon as the cosmological dark matter, limits at 90% confidence level with m_{V} from 0.1 to 4.0 keV/c^{2} are set from 449.6 kg-day data, with a minimum of κ=1.3×10^{-15} at m_{V}=200 eV/c^{2}.

6.
Phys Rev Lett ; 123(22): 221301, 2019 Nov 29.
Article in English | MEDLINE | ID: mdl-31868422

ABSTRACT

We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6 GeV/c^{2} among WIMP AM measurements to date.

7.
Phys Rev Lett ; 123(16): 161301, 2019 Oct 18.
Article in English | MEDLINE | ID: mdl-31702340

ABSTRACT

We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (m_{χ}) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in m_{χ} are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σ_{χN}^{SI} at 90% confidence level are derived as 2×10^{-32}∼7×10^{-35} cm^{2} for TI analysis at m_{χ}∼50-180 MeV/c^{2}, and 3×10^{-32}∼9×10^{-38} cm^{2} for AM analysis at m_{χ}∼75 MeV/c^{2}-3.0 GeV/c^{2}.

8.
Phys Rev Lett ; 120(24): 241301, 2018 Jun 15.
Article in English | MEDLINE | ID: mdl-29956956

ABSTRACT

We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8×10^{-42} and 3×10^{-36} cm^{2} at a 90% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass (m_{χ}) of 5 GeV/c^{2} are achieved. The lower reach of m_{χ} is extended to 2 GeV/c^{2}.

10.
Endoscopy ; 45(7): 575-8, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23801315

ABSTRACT

We present 19 cases in which argon plasma coagulation (APC) was used as curative initial treatment for 5 low-grade esophageal squamous intraepithelial neoplasias (ESINs), 12 high-grade ESINs, and 2 early esophageal squamous cell carcinomas (ESCCs). Complete response was defined as the absence of tumor from any biopsy taken from the ablated lesion. At follow-up endoscopy 2 - 4 months after APC, 94.7 % of patients had achieved complete response in a single treatment session. Only one patient with high-grade ESIN showed local recurrence. This patient underwent additional APC and showed complete response at 12 months after initial APC. At the 12-month follow-up endoscopy, again 94.7 % had a complete response. The exception was one patient with local recurrence, who underwent additional APC. After the 12-month follow-up endoscopy, no patient showed local recurrence during a median follow-up of 22 months. No stricture requiring endoscopic dilation occurred after the procedure. This study suggests that APC is a feasible and effective treatment modality for ESIN and early ESCC.


Subject(s)
Argon Plasma Coagulation , Carcinoma, Squamous Cell/surgery , Esophageal Neoplasms/surgery , Precancerous Conditions/surgery , Aged , Argon Plasma Coagulation/instrumentation , Argon Plasma Coagulation/methods , Carcinoma, Squamous Cell/pathology , Esophageal Neoplasms/pathology , Esophagoscopy , Feasibility Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Precancerous Conditions/pathology , Retrospective Studies , Treatment Outcome
11.
Endoscopy ; 44(10): 949-52, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22987215

ABSTRACT

Extremely well-differentiated tubular adenocarcinomas (EWDAs) of the stomach are characterized by surface maturation and their mimicking of intestinal metaplasia. Endoscopically, intramucosal EWDAs are frequently ill defined with indistinct borders due to the pallor of the neoplastic mucosa and the lack of contrast against the background atrophic and metaplastic mucosa. We evaluated the effectiveness of endoscopic resection for EWDAs after endoscopic submucosal dissection (ESD). Among 872 patients with early gastric cancer, 17 EWDAs were identified (1.9 %). Endoscopically, the flat or depressed type was significantly more common among EWDAs (88.2 %) than among early gastric cancers of other histologies (37.8 %; P < 0.01). The discrepancy between endoscopically estimated tumor size and tumor size as confirmed in pathology reports was significantly greater among EWDAs (18.4 ±â€Š22.0  mm) than among others (5.8 ±â€Š7.5  mm). Involvement of the lateral resection margin was more common (29.4 % vs. 2.5 %; P < 0.05), and complete resection was achieved less often in EWDAs (47.1 % vs. 80.4 %; P = 0.01) compared to the others. EWDAs are associated with higher rates of incomplete resection after ESD, especially along the lateral margins. Pathologists should alert endoscopists when this diagnosis is made, with its associated risks; and endoscopists should pay particular attention to the extent of these tumors during resection.


Subject(s)
Adenocarcinoma/surgery , Gastric Mucosa/surgery , Gastroscopy/methods , Stomach Neoplasms/surgery , Adenocarcinoma/pathology , Female , Gastric Mucosa/pathology , Humans , Male , Middle Aged , Retrospective Studies , Stomach Neoplasms/pathology , Treatment Outcome
12.
Transplant Proc ; 40(8): 2700-3, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18929839

ABSTRACT

Establishing an easy and reproducible model for hepatic fibrosis is absolutely necessary for research on liver reperfusion injury. We compared the characteristics of several hepatic cirrhosis models in terms of the degree of fibrosis, reproducibility, histologic characteristics, and success rate to achieve sufficient fibrosis. In mice & rats, we administered three different hepatotoxic drugs (thioacetamide, dimethylnitrosamine, and carbon tetrachloride [CCl4]) through two different routes (oral feeding and intraperitoneal injection). The animals fed thioacetamide exhibited little fibrosis; rather, more inflammatory cells infiltrated into periportal areas with bile duct proliferation. The livers from hosts administered dimethylnitrosamine showed greater early injury and severe inflammatory reactions in the peritoneal cavity. The liver showed a marked degree of piecemeal necrosis with limited fibrosis. The mice administered a 50% solution of CCl4 (2 mL/kg orally) tolerated the entire induction period of 12 weeks. The degree of fibrosis correlated well with the duration of induction. Livers from hosts administered CCl4 orally twice a week for 10 weeks was the most effective to achieve sufficient fibrosis and greatest reproducibility with acceptable animal survival.


Subject(s)
Dimethylnitrosamine/toxicity , Liver Cirrhosis/pathology , Thioacetamide/toxicity , Animals , Carbon Tetrachloride Poisoning/pathology , Disease Models, Animal , Liver Cirrhosis/chemically induced , Liver Cirrhosis/mortality , Male , Mice , Mice, Inbred C57BL , Rats , Rats, Sprague-Dawley
13.
Ann N Y Acad Sci ; 1099: 16-28, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17303823

ABSTRACT

K+-dependent Na+/Ca2+ exchangers (NCKX) have been shown to play important roles in physiological processes as diverse as phototransduction in rod photoreceptors, motor learning and memory in mice, and skin pigmentation in humans. Most structure-function studies on NCKX proteins have been carried out on the NCKX2 isoform, but sequence similarity suggests that the results obtained with the NCKX2 isoform are likely to apply to all NCKX1-5 members of the human SLC24 gene family. Here we review our recent work on the NCKX2 protein concerning the topological arrangement of transmembrane segments carrying out cation transport, and concerning residues important for transport function and cation binding.


Subject(s)
Sodium-Calcium Exchanger/physiology , Amino Acid Sequence , DNA, Complementary , Fluorescence , Humans , Models, Molecular , Molecular Sequence Data , Sequence Homology, Amino Acid , Sodium-Calcium Exchanger/chemistry , Sodium-Calcium Exchanger/genetics , Structure-Activity Relationship
14.
Neuroscience ; 118(1): 205-16, 2003.
Article in English | MEDLINE | ID: mdl-12676150

ABSTRACT

Previous studies have shown significant correlated discharges (noise correlation) and synergistic information coding among adjacent cortical neurons. In order to investigate whether such interactions are present at an earlier stage of sensory processing, we compared noise correlation and synergistic information transmission in the ventral posterolateral nucleus (VPLn) of thalamus and primary somatosensory cortex (SI) of anesthetized rats. A hind paw was stimulated electrically and responses of several neighboring neurons were recorded simultaneously with a tetrode. Analyses indicated that noise correlation in the SI was about four times higher than in the VPLn, and, interestingly, it was significantly reduced following sensory stimulation in both regions. Spike count distributions of individual VPLn units contained higher amounts of information about the delivery of external stimulation compared with those of SI units. When simultaneously recorded units were considered together, transmission of information was more interactive (synergistic or redundant) among SI than VPLn units. On average, information transmission was independent in the VPLn, but synergistic in the SI. The difference in synergistic information coding was largely attributable to different levels of noise correlation and their modulation by external sensory stimulation. These results indicate that neuronal interactions are relatively low at the thalamic level, but much enhanced at the cortical level along the somatosensory pathway. The enhanced neuronal interactions in the cortex may reflect the role of cortex in extracting higher features of sensory stimuli.


Subject(s)
Afferent Pathways/physiology , Mechanoreceptors/physiology , Somatosensory Cortex/physiology , Touch/physiology , Ventral Thalamic Nuclei/physiology , Action Potentials/physiology , Animals , Artifacts , Cell Communication/physiology , Electric Stimulation , Hindlimb/innervation , Male , Nerve Net/physiology , Rats , Rats, Sprague-Dawley , Skin/innervation , Synaptic Transmission/physiology
15.
Invest Radiol ; 29(1): 54-8, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8144338

ABSTRACT

RATIONALE AND OBJECTIVES: The authors assessed the effect of noise on the detectability of rib fractures by residents. METHODS: Eight radiology residents read chest posterior-anterior radiographs of 92 subjects with rib fracture(s) and 28 normal subjects to detect rib fracture(s) according to a five-point scale of confidence, under quiet and "noisy" conditions. Each individual's attitude toward noise was measured by a multiple-choice questionnaire. RESULTS: The readers were divided into two groups depending on the questionnaire result: group A readers were accustomed to a quiet environment, and group B readers were accustomed to noisy environments or were unaffected by noise. Group A's performance, measured by the area (Az) under the receiver operating characteristic (ROC) curve, was better in quiet conditions when compared with their performance in noisy conditions; however, the opposite tendency was observed for group B. There was a significant individual difference of performance in response to noise. CONCLUSION: Effect of noise on the detection of rib fractures depends on an individual's attitude toward sound and noise.


Subject(s)
Attitude of Health Personnel , Internship and Residency , Noise, Occupational/adverse effects , Rib Fractures/diagnostic imaging , Humans , ROC Curve , Radiography , Rib Fractures/epidemiology , Surveys and Questionnaires , Task Performance and Analysis
16.
Surg Laparosc Endosc Percutan Tech ; 10(6): 364-7, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11147910

ABSTRACT

We reviewed the results of 339 consecutive appendectomies, including perforated appendicitis, to assess the advantages of the laparoscopic approach for acute appendicitis. Three hundred and eighty-eight patients underwent appendectomy at the Keimyung University Kyungju Dongsan Hospital between March 1994 and June 1996; 339 patients were treated using laparoscopic appendectomy (LA), and 49 patients who were treated with open appendectomy. Special emphasis was given to the results of LA in 27 patients with perforated appendicitis. The mean duration of the operating time for LA was 48.9 minutes. For six patients (1.8%), the procedure was converted to open surgery. Minor complications developed in eight patients (2.4%). There were no complications in the 27 patients with perforated appendicitis. Our experience with LA in perforated appendicitis is limited, but our results show that LA is a safe and acceptable procedure for all forms of acute appendicitis.


Subject(s)
Appendectomy/adverse effects , Appendectomy/methods , Appendicitis/surgery , Intestinal Perforation/surgery , Laparoscopy/adverse effects , Laparoscopy/methods , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Feasibility Studies , Female , Humans , Length of Stay/statistics & numerical data , Male , Retrospective Studies , Rupture, Spontaneous
20.
Gynecol Oncol ; 22(1): 59-64, 1985 Sep.
Article in English | MEDLINE | ID: mdl-4040490

ABSTRACT

Two cases with squamous cell carcinoma of the cervix stage IIB with primary tumor mass about 2 X 2 X 2 cm were treated with primary chemotherapy of cis-platinum, 20 micrograms/m2 body surface intravenously daily for 5 consecutive days. Papanicolaou smear turned negative after two courses of chemotherapy in both cases. One of those was followed by radical hysterectomy with lymphadenectomy which confirmed that there was no evidence of disease by histopathology. The third case with stage IIIB and bulky tumor with involvement of pelvic and left common iliac lymph nodes was treated with simple hysterectomy followed by adjuvant chemotherapy with the same medication described above. Complete responses were obtained in all three cases and they are now doing well in a tumor-free state for 26, 30, and 28 months, respectively.


Subject(s)
Carcinoma, Squamous Cell/drug therapy , Uterine Cervical Neoplasms/drug therapy , Carcinoma, Squamous Cell/surgery , Cisplatin/therapeutic use , Combined Modality Therapy , Female , Humans , Middle Aged , Uterine Cervical Neoplasms/surgery
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